1 <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>The Altus Metrum System</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="book"><div class="titlepage"><div><div><h1 class="title"><a name="idp4969824"></a>The Altus Metrum System</h1></div><div><h2 class="subtitle">An Owner's Manual for Altus Metrum Rocketry Electronics</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Bdale</span> <span class="surname">Garbee</span></h3></div></div><div><div class="author"><h3 class="author"><span class="firstname">Keith</span> <span class="surname">Packard</span></h3></div></div><div><div class="author"><h3 class="author"><span class="firstname">Bob</span> <span class="surname">Finch</span></h3></div></div><div><div class="author"><h3 class="author"><span class="firstname">Anthony</span> <span class="surname">Towns</span></h3></div></div><div><p class="copyright">Copyright © 2015 Bdale Garbee and Keith Packard</p></div><div><div class="legalnotice"><a name="idp32366224"></a><p>
2 This document is released under the terms of the
3 <a class="ulink" href="http://creativecommons.org/licenses/by-sa/3.0/" target="_top">
4 Creative Commons ShareAlike 3.0
7 </p></div></div><div><div class="revhistory"><table style="border-style:solid; width:100%;" summary="Revision History"><tr><th align="left" valign="top" colspan="2"><b>Revision History</b></th></tr><tr><td align="left">Revision 1.6</td><td align="left">8 January 2015</td></tr><tr><td align="left" colspan="2">
8 Major release adding TeleDongle v3.0 support.
9 </td></tr><tr><td align="left">Revision 1.5</td><td align="left">6 September 2014</td></tr><tr><td align="left" colspan="2">
10 Major release adding EasyMega support.
11 </td></tr><tr><td align="left">Revision 1.4.1</td><td align="left">20 June 2014</td></tr><tr><td align="left" colspan="2">
12 Minor release fixing some installation bugs.
13 </td></tr><tr><td align="left">Revision 1.4</td><td align="left">15 June 2014</td></tr><tr><td align="left" colspan="2">
14 Major release adding TeleGPS support.
15 </td></tr><tr><td align="left">Revision 1.3.2</td><td align="left">24 January 2014</td></tr><tr><td align="left" colspan="2">
16 Bug fixes for TeleMega and AltosUI.
17 </td></tr><tr><td align="left">Revision 1.3.1</td><td align="left">21 January 2014</td></tr><tr><td align="left" colspan="2">
18 Bug fixes for TeleMega and TeleMetrum v2.0 along with a few
19 small UI improvements.
20 </td></tr><tr><td align="left">Revision 1.3</td><td align="left">12 November 2013</td></tr><tr><td align="left" colspan="2">
21 Updated for software version 1.3. Version 1.3 adds support
22 for TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini
23 and fixes bugs in AltosUI and the AltOS firmware.
24 </td></tr><tr><td align="left">Revision 1.2.1</td><td align="left">21 May 2013</td></tr><tr><td align="left" colspan="2">
25 Updated for software version 1.2. Version 1.2 adds support
26 for TeleBT and AltosDroid. It also adds a few minor features
27 and fixes bugs in AltosUI and the AltOS firmware.
28 </td></tr><tr><td align="left">Revision 1.2</td><td align="left">18 April 2013</td></tr><tr><td align="left" colspan="2">
29 Updated for software version 1.2. Version 1.2 adds support
30 for MicroPeak and the MicroPeak USB interface.
31 </td></tr><tr><td align="left">Revision 1.1.1</td><td align="left">16 September 2012</td></tr><tr><td align="left" colspan="2">
32 Updated for software version 1.1.1 Version 1.1.1 fixes a few
33 bugs found in version 1.1.
34 </td></tr><tr><td align="left">Revision 1.1</td><td align="left">13 September 2012</td></tr><tr><td align="left" colspan="2">
35 Updated for software version 1.1. Version 1.1 has new
36 features but is otherwise compatible with version 1.0.
37 </td></tr><tr><td align="left">Revision 1.0</td><td align="left">24 August 2011</td></tr><tr><td align="left" colspan="2">
38 Updated for software version 1.0. Note that 1.0 represents a
39 telemetry format change, meaning both ends of a link
40 (TeleMetrum/TeleMini and TeleDongle) must be updated or
41 communications will fail.
42 </td></tr><tr><td align="left">Revision 0.9</td><td align="left">18 January 2011</td></tr><tr><td align="left" colspan="2">
43 Updated for software version 0.9. Note that 0.9 represents a
44 telemetry format change, meaning both ends of a link (TeleMetrum and
45 TeleDongle) must be updated or communications will fail.
46 </td></tr><tr><td align="left">Revision 0.8</td><td align="left">24 November 2010</td></tr><tr><td align="left" colspan="2">Updated for software version 0.8 </td></tr></table></div></div></div><hr></div><div class="dedication"><div class="titlepage"><div><div><h1 class="title"><a name="idp31667056"></a>Acknowledgments</h1></div></div></div><p>
47 Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing “The
48 Mere-Mortals Quick Start/Usage Guide to the Altus Metrum Starter
49 Kit” which formed the basis of the original Getting Started chapter
50 in this manual. Bob was one of our first customers for a production
51 TeleMetrum, and his continued enthusiasm and contributions
52 are immensely gratifying and highly appreciated!
54 And thanks to Anthony (AJ) Towns for major contributions including
55 the AltosUI graphing and site map code and associated documentation.
56 Free software means that our customers and friends can become our
57 collaborators, and we certainly appreciate this level of
60 Have fun using these products, and we hope to meet all of you
61 out on the rocket flight line somewhere.
62 </p><div class="literallayout"><p><br>
63 Bdale Garbee, KB0G<br>
64 NAR #87103, TRA #12201<br>
66 Keith Packard, KD7SQG<br>
67 NAR #88757, TRA #12200<br>
69 </p></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="chapter"><a href="#idp31483344">1. Introduction and Overview</a></span></dt><dt><span class="chapter"><a href="#idp31491792">2. Getting Started</a></span></dt><dt><span class="chapter"><a href="#idp31501248">3. Handling Precautions</a></span></dt><dt><span class="chapter"><a href="#idp31506736">4. Altus Metrum Hardware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp31507408">1. General Usage Instructions</a></span></dt><dd><dl><dt><span class="section"><a href="#idp31509696">1.1. Hooking Up Lithium Polymer Batteries</a></span></dt><dt><span class="section"><a href="#idp31512656">1.2. Hooking Up Pyro Charges</a></span></dt><dt><span class="section"><a href="#idp31514736">1.3. Hooking Up a Power Switch</a></span></dt><dt><span class="section"><a href="#idp31517952">1.4. Using a Separate Pyro Battery</a></span></dt><dt><span class="section"><a href="#idp36999216">1.5. Using a Different Kind of Battery</a></span></dt></dl></dd><dt><span class="section"><a href="#idp34636960">2. Specifications</a></span></dt><dt><span class="section"><a href="#idp37090320">3. TeleMetrum</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37095216">3.1. TeleMetrum Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37114432">3.2. Using a Separate Pyro Battery with TeleMetrum</a></span></dt><dt><span class="section"><a href="#idp37117680">3.3. Using an Active Switch with TeleMetrum</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37119808">4. TeleMini v1.0</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37124704">4.1. TeleMini v1.0 Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37144048">4.2. Using a Separate Pyro Battery with TeleMini v1.0</a></span></dt><dt><span class="section"><a href="#idp37147424">4.3. Using an Active Switch with TeleMini v1.0</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37149632">5. TeleMini v2.0</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37153648">5.1. TeleMini v2.0 Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37176032">5.2. Using a Separate Pyro Battery with TeleMini v2.0</a></span></dt><dt><span class="section"><a href="#idp37179232">5.3. Using an Active Switch with TeleMini v2.0</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37181328">6. EasyMini</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37185184">6.1. EasyMini Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37207568">6.2. Using a Separate Pyro Battery with EasyMini</a></span></dt><dt><span class="section"><a href="#idp37210752">6.3. Using an Active Switch with EasyMini</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37212848">7. TeleMega</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37216816">7.1. TeleMega Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37254320">7.2. Using a Separate Pyro Battery with TeleMega</a></span></dt><dt><span class="section"><a href="#idp37255920">7.3. Using Only One Battery With TeleMega</a></span></dt><dt><span class="section"><a href="#idp37257840">7.4. Using an Active Switch with TeleMega</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37259888">8. EasyMega</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37263856">8.1. EasyMega Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37301456">8.2. Using a Separate Pyro Battery with EasyMega</a></span></dt><dt><span class="section"><a href="#idp37303056">8.3. Using Only One Battery With EasyMega</a></span></dt><dt><span class="section"><a href="#idp37304976">8.4. Using an Active Switch with EasyMega</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37307024">9. Flight Data Recording</a></span></dt><dt><span class="section"><a href="#idp37337792">10. Installation</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp37344528">5. System Operation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37345168">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp37413664">2. GPS </a></span></dt><dt><span class="section"><a href="#idp37416448">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp37427744">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp37430496">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp37434496">6. APRS</a></span></dt><dt><span class="section"><a href="#idp37458816">7. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37460736">7.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp37462784">7.2. Callsign</a></span></dt><dt><span class="section"><a href="#idp37464320">7.3. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp37465616">7.4. Telemetry baud rate</a></span></dt><dt><span class="section"><a href="#idp37467184">7.5. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp37468656">7.6. APRS SSID</a></span></dt><dt><span class="section"><a href="#idp37470000">7.7. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp37472592">7.8. Apogee Lockout</a></span></dt><dt><span class="section"><a href="#idp37474320">7.9. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp37476016">7.10. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp37478160">7.11. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp37480272">7.12. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp37481968">7.13. Configurable Pyro Channels</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="#idp37504576">6. AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37508192">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37521120">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp37536752">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp37542208">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp37549072">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp37555504">1.5. Table</a></span></dt><dt><span class="section"><a href="#idp37559088">1.6. Site Map</a></span></dt><dt><span class="section"><a href="#idp37565408">1.7. Ignitor</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37569184">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp37573136">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp37575168">4. Graph Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37577552">4.1. Flight Graph</a></span></dt><dt><span class="section"><a href="#idp37582000">4.2. Configure Graph</a></span></dt><dt><span class="section"><a href="#idp37585664">4.3. Flight Statistics</a></span></dt><dt><span class="section"><a href="#idp37589184">4.4. Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37593040">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37594608">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp37596960">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37598448">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37610752">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp37612320">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp37613936">6.3. Apogee Lockoug</a></span></dt><dt><span class="section"><a href="#idp37616240">6.4. Frequency</a></span></dt><dt><span class="section"><a href="#idp37617744">6.5. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp37619392">6.6. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp37620688">6.7. Telemetry baud rate</a></span></dt><dt><span class="section"><a href="#idp37622256">6.8. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp37623824">6.9. APRS SSID</a></span></dt><dt><span class="section"><a href="#idp37625152">6.10. Callsign</a></span></dt><dt><span class="section"><a href="#idp37626464">6.11. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp37627904">6.12. Ignitor Firing Mode</a></span></dt><dt><span class="section"><a href="#idp37634816">6.13. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp37640048">6.14. Beeper Frequency</a></span></dt><dt><span class="section"><a href="#idp37641504">6.15. Configure Pyro Channels</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37647888">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37651392">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp37656416">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp37658416">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp37660656">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp37662160">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp37663440">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp37664944">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37666576">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37678080">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp37679648">8.2. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp37681168">8.3. Telemetry Rate</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37682640">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp37684304">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp37689936">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp37693808">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp37707856">13. Monitor Idle</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp37709952">7. AltosDroid</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37712336">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp37714272">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp37716272">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp37717728">4. AltosDroid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37719040">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37732592">5. Downloading Flight Logs</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp37734256">8. Using Altus Metrum Products</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37734896">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp37736800">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp37739328">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp37753120">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp37756432">5. Future Plans</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp37760272">9. Altimeter Installation Recommendations</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37761728">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp37766560">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp37772128">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp37776912">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp37784480">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp37787280">6. Ground Testing</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp37790448">10. Updating Device Firmware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37794528">1.
70 Updating TeleMega, TeleMetrum v2, EasyMega, EasyMini or
71 TeleDongle v3 Firmware
72 </a></span></dt><dd><dl><dt><span class="section"><a href="#idp37803664">1.1. Recovering From Self-Flashing Failure</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37824016">2. Pair Programming</a></span></dt><dt><span class="section"><a href="#idp37825472">3. Updating TeleMetrum v1.x Firmware</a></span></dt><dt><span class="section"><a href="#idp37838736">4. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp37852352">5. Updating TeleDongle v0.2 Firmware</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp37869568">11. Hardware Specifications</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37870208">1.
73 TeleMega Specifications
74 </a></span></dt><dt><span class="section"><a href="#idp37881680">2.
75 EasyMega Specifications
76 </a></span></dt><dt><span class="section"><a href="#idp37891424">3.
77 TeleMetrum v2 Specifications
78 </a></span></dt><dt><span class="section"><a href="#idp37901984">4. TeleMetrum v1 Specifications</a></span></dt><dt><span class="section"><a href="#idp37912544">5.
79 TeleMini v2.0 Specifications
80 </a></span></dt><dt><span class="section"><a href="#idp37921376">6.
81 TeleMini v1.0 Specifications
82 </a></span></dt><dt><span class="section"><a href="#idp37930176">7.
83 EasyMini Specifications
84 </a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp37938288">12. FAQ</a></span></dt><dt><span class="appendix"><a href="#idp37947888">A. Notes for Older Software</a></span></dt><dt><span class="appendix"><a href="#idp37969232">B. Drill Templates</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37970400">1. TeleMega template</a></span></dt><dt><span class="section"><a href="#idp37987088">2. EasyMega template</a></span></dt><dt><span class="section"><a href="#idp37991472">3. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp37995856">4. TeleMini v2/EasyMini template</a></span></dt><dt><span class="section"><a href="#idp38000256">5. TeleMini v1 template</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp38004768">C. Calibration</a></span></dt><dd><dl><dt><span class="section"><a href="#idp38006320">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp38011520">2. TeleMetrum, TeleMega and EasyMega Accelerometers</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp38016624">D. Igniter Current</a></span></dt><dd><dl><dt><span class="section"><a href="#idp38017888">1. Current Products</a></span></dt><dt><span class="section"><a href="#idp38021328">2. Version 1 Products</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp38023664">E. Release Notes</a></span></dt></dl></div><div class="list-of-tables"><p><b>List of Tables</b></p><dl><dt>4.1. <a href="#idp33882000">Altus Metrum Electronics</a></dt><dt>4.2. <a href="#idp37049568">Altus Metrum Boards</a></dt><dt>4.3. <a href="#idp37096528">TeleMetrum Screw Terminals</a></dt><dt>4.4. <a href="#idp37126144">TeleMini v1.0 Connections</a></dt><dt>4.5. <a href="#idp37155056">TeleMini v2.0 Connections</a></dt><dt>4.6. <a href="#idp37186592">EasyMini Connections</a></dt><dt>4.7. <a href="#idp37217984">TeleMega Screw Terminals</a></dt><dt>4.8. <a href="#idp37265024">EasyMega Screw Terminals</a></dt><dt>4.9. <a href="#idp37308432">Data Storage on Altus Metrum altimeters</a></dt><dt>5.1. <a href="#idp37350528">AltOS Modes</a></dt><dt>5.2. <a href="#idp37387712">Pad/Idle Indications</a></dt><dt>5.3. <a href="#idp37438304">Altus Metrum APRS Comments</a></dt></dl></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp31483344"></a>Chapter 1. Introduction and Overview</h1></div></div></div><p>
85 Welcome to the Altus Metrum community! Our circuits and software reflect
86 our passion for both hobby rocketry and Free Software. We hope their
87 capabilities and performance will delight you in every way, but by
88 releasing all of our hardware and software designs under open licenses,
89 we also hope to empower you to take as active a role in our collective
92 The first device created for our community was TeleMetrum, a dual
93 deploy altimeter with fully integrated GPS and radio telemetry
94 as standard features, and a “companion interface” that will
95 support optional capabilities in the future. The latest version
96 of TeleMetrum, v2.0, has all of the same features but with
97 improved sensors and radio to offer increased performance.
99 Our second device was TeleMini, a dual deploy altimeter with
100 radio telemetry and radio direction finding. The first version
101 of this device was only 13mm by 38mm (½ inch by 1½ inches) and
102 could fit easily in an 18mm air-frame. The latest version, v2.0,
103 includes a beeper, USB data download and extended on-board
104 flight logging, along with an improved barometric sensor.
106 TeleMega is our most sophisticated device, including six pyro
107 channels (four of which are fully programmable), integrated GPS,
108 integrated gyroscopes for staging/air-start inhibit and high
109 performance telemetry.
111 EasyMini is a dual-deploy altimeter with logging and built-in
114 EasyMega is essentially a TeleMega board with the GPS receiver
115 and telemetry transmitter removed. It offers the same 6 pyro
116 channels and integrated gyroscopes for staging/air-start inhibit.
118 TeleDongle v0.2 was our first ground station, providing a USB to RF
119 interfaces for communicating with the altimeters. Combined with
120 your choice of antenna and notebook computer, TeleDongle and our
121 associated user interface software form a complete ground
122 station capable of logging and displaying in-flight telemetry,
123 aiding rocket recovery, then processing and archiving flight
124 data for analysis and review. The latest version, TeleDongle
125 v3, has all new electronics with a higher performance radio
128 For a slightly more portable ground station experience that also
129 provides direct rocket recovery support, TeleBT offers flight
130 monitoring and data logging using a Bluetooth™ connection between
131 the receiver and an Android device that has the AltosDroid
132 application installed from the Google Play store.
134 More products will be added to the Altus Metrum family over time, and
135 we currently envision that this will be a single, comprehensive manual
136 for the entire product family.
137 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp31491792"></a>Chapter 2. Getting Started</h1></div></div></div><p>
138 The first thing to do after you check the inventory of parts in your
139 “starter kit” is to charge the battery.
141 For TeleMetrum, TeleMega and EasyMega, the battery can be charged by plugging it into the
142 corresponding socket of the device and then using the USB
143 cable to plug the flight computer into your computer's USB socket. The
144 on-board circuitry will charge the battery whenever it is plugged
145 in, because the on-off switch does NOT control the
148 On TeleMetrum v1 boards, when the GPS chip is initially
149 searching for satellites, TeleMetrum will consume more current
150 than it pulls from the USB port, so the battery must be
151 attached in order to get satellite lock. Once GPS is locked,
152 the current consumption goes back down enough to enable charging
153 while running. So it's a good idea to fully charge the battery
154 as your first item of business so there is no issue getting and
155 maintaining satellite lock. The yellow charge indicator led
156 will go out when the battery is nearly full and the charger goes
157 to trickle charge. It can take several hours to fully recharge a
158 deeply discharged battery.
160 TeleMetrum v2.0, TeleMega and EasyMega use a higher power battery charger,
161 allowing them to charge the battery while running the board at
162 maximum power. When the battery is charging, or when the board
163 is consuming a lot of power, the red LED will be lit. When the
164 battery is fully charged, the green LED will be lit. When the
165 battery is damaged or missing, both LEDs will be lit, which
168 The Lithium Polymer TeleMini and EasyMini battery can be charged by
169 disconnecting it from the board and plugging it into a
170 standalone battery charger such as the LipoCharger product
171 included in TeleMini Starter Kits, and connecting that via a USB
172 cable to a laptop or other USB power source.
174 You can also choose to use another battery with TeleMini v2.0
175 and EasyMini, anything supplying between 4 and 12 volts should
176 work fine (like a standard 9V battery), but if you are planning
177 to fire pyro charges, ground testing is required to verify that
178 the battery supplies enough current to fire your chosen e-matches.
180 The other active device in the starter kit is the TeleDongle USB to
181 RF interface. If you plug it in to your Mac or Linux computer it should
182 “just work”, showing up as a serial port device. Windows systems need
183 driver information that is part of the AltOS download to know that the
184 existing USB modem driver will work. We therefore recommend installing
185 our software before plugging in TeleDongle if you are using a Windows
186 computer. If you are using an older version of Linux and are having
187 problems, try moving to a fresher kernel (2.6.33 or newer).
189 Next you should obtain and install the AltOS software. The AltOS
190 distribution includes the AltosUI ground station program, current
192 images for all of the hardware, and a number of standalone
193 utilities that are rarely needed. Pre-built binary packages are
194 available for Linux, Microsoft Windows, and recent MacOSX
195 versions. Full source code and build instructions are also
196 available. The latest version may always be downloaded from
197 <a class="ulink" href="http://altusmetrum.org/AltOS" target="_top">http://altusmetrum.org/AltOS</a>.
199 If you're using a TeleBT instead of the TeleDongle, you'll want to
200 install the AltosDroid application from the Google Play store on an
201 Android device. You don't need a data plan to use AltosDroid, but
202 without network access, the Map view will be less useful as it
203 won't contain any map data. You can also use TeleBT connected
204 over USB with your laptop computer; it acts exactly like a
205 TeleDongle. Anywhere this manual talks about TeleDongle, you can
206 also read that as 'and TeleBT when connected via USB'.
207 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp31501248"></a>Chapter 3. Handling Precautions</h1></div></div></div><p>
208 All Altus Metrum products are sophisticated electronic devices.
209 When handled gently and properly installed in an air-frame, they
210 will deliver impressive results. However, as with all electronic
211 devices, there are some precautions you must take.
213 The Lithium Polymer rechargeable batteries have an
214 extraordinary power density. This is great because we can fly with
215 much less battery mass than if we used alkaline batteries or previous
216 generation rechargeable batteries... but if they are punctured
217 or their leads are allowed to short, they can and will release their
219 Thus we recommend that you take some care when handling our batteries
220 and consider giving them some extra protection in your air-frame. We
221 often wrap them in suitable scraps of closed-cell packing foam before
222 strapping them down, for example.
224 The barometric sensors used on all of our flight computers are
225 sensitive to sunlight. In normal mounting situations, the baro sensor
226 and all of the other surface mount components
227 are “down” towards whatever the underlying mounting surface is, so
228 this is not normally a problem. Please consider this when designing an
229 installation in an air-frame with a see-through plastic payload bay. It
230 is particularly important to
231 consider this with TeleMini v1.0, both because the baro sensor is on the
232 “top” of the board, and because many model rockets with payload bays
233 use clear plastic for the payload bay! Replacing these with an opaque
234 cardboard tube, painting them, or wrapping them with a layer of masking
235 tape are all reasonable approaches to keep the sensor out of direct
238 The barometric sensor sampling port must be able to “breathe”,
239 both by not being covered by foam or tape or other materials that might
240 directly block the hole on the top of the sensor, and also by having a
241 suitable static vent to outside air.
243 As with all other rocketry electronics, Altus Metrum altimeters must
244 be protected from exposure to corrosive motor exhaust and ejection
246 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp31506736"></a>Chapter 4. Altus Metrum Hardware</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp31507408">1. General Usage Instructions</a></span></dt><dd><dl><dt><span class="section"><a href="#idp31509696">1.1. Hooking Up Lithium Polymer Batteries</a></span></dt><dt><span class="section"><a href="#idp31512656">1.2. Hooking Up Pyro Charges</a></span></dt><dt><span class="section"><a href="#idp31514736">1.3. Hooking Up a Power Switch</a></span></dt><dt><span class="section"><a href="#idp31517952">1.4. Using a Separate Pyro Battery</a></span></dt><dt><span class="section"><a href="#idp36999216">1.5. Using a Different Kind of Battery</a></span></dt></dl></dd><dt><span class="section"><a href="#idp34636960">2. Specifications</a></span></dt><dt><span class="section"><a href="#idp37090320">3. TeleMetrum</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37095216">3.1. TeleMetrum Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37114432">3.2. Using a Separate Pyro Battery with TeleMetrum</a></span></dt><dt><span class="section"><a href="#idp37117680">3.3. Using an Active Switch with TeleMetrum</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37119808">4. TeleMini v1.0</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37124704">4.1. TeleMini v1.0 Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37144048">4.2. Using a Separate Pyro Battery with TeleMini v1.0</a></span></dt><dt><span class="section"><a href="#idp37147424">4.3. Using an Active Switch with TeleMini v1.0</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37149632">5. TeleMini v2.0</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37153648">5.1. TeleMini v2.0 Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37176032">5.2. Using a Separate Pyro Battery with TeleMini v2.0</a></span></dt><dt><span class="section"><a href="#idp37179232">5.3. Using an Active Switch with TeleMini v2.0</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37181328">6. EasyMini</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37185184">6.1. EasyMini Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37207568">6.2. Using a Separate Pyro Battery with EasyMini</a></span></dt><dt><span class="section"><a href="#idp37210752">6.3. Using an Active Switch with EasyMini</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37212848">7. TeleMega</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37216816">7.1. TeleMega Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37254320">7.2. Using a Separate Pyro Battery with TeleMega</a></span></dt><dt><span class="section"><a href="#idp37255920">7.3. Using Only One Battery With TeleMega</a></span></dt><dt><span class="section"><a href="#idp37257840">7.4. Using an Active Switch with TeleMega</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37259888">8. EasyMega</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37263856">8.1. EasyMega Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp37301456">8.2. Using a Separate Pyro Battery with EasyMega</a></span></dt><dt><span class="section"><a href="#idp37303056">8.3. Using Only One Battery With EasyMega</a></span></dt><dt><span class="section"><a href="#idp37304976">8.4. Using an Active Switch with EasyMega</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37307024">9. Flight Data Recording</a></span></dt><dt><span class="section"><a href="#idp37337792">10. Installation</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp31507408"></a>1. General Usage Instructions</h2></div></div></div><p>
247 Here are general instructions for hooking up an Altus Metrum
248 flight computer. Instructions specific to each model will be
249 found in the section devoted to that model below.
251 To prevent electrical interference from affecting the
252 operation of the flight computer, it's important to always
253 twist pairs of wires connected to the board. Twist the switch
254 leads, the pyro leads and the battery leads. This reduces
255 interference through a mechanism called common mode rejection.
256 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp31509696"></a>1.1. Hooking Up Lithium Polymer Batteries</h3></div></div></div><p>
257 All Altus Metrum flight computers have a two pin JST PH
258 series connector to connect up a single-cell Lithium Polymer
259 cell (3.7V nominal). You can purchase matching batteries
260 from the Altus Metrum store, or other vendors, or you can
261 make your own. Pin 1 of the connector is positive, pin 2 is
262 negative. Spark Fun sells a cable with the connector
263 attached, which they call a <a class="ulink" href="https://www.sparkfun.com/products/9914" target="_top">JST Jumper 2
266 Many RC vendors also sell lithium polymer batteries with
267 this same connector. All that we have found use the opposite
268 polarity, and if you use them that way, you will damage or
269 destroy the flight computer.
270 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp31512656"></a>1.2. Hooking Up Pyro Charges</h3></div></div></div><p>
271 Altus Metrum flight computers always have two screws for
272 each pyro charge. This means you shouldn't need to put two
273 wires into a screw terminal or connect leads from pyro
274 charges together externally.
276 On the flight computer, one lead from each charge is hooked
277 to the positive battery terminal through the power switch.
278 The other lead is connected through the pyro circuit, which
279 is connected to the negative battery terminal when the pyro
281 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp31514736"></a>1.3. Hooking Up a Power Switch</h3></div></div></div><p>
282 Altus Metrum flight computers need an external power switch
283 to turn them on. This disconnects both the computer and the
284 pyro charges from the battery, preventing the charges from
285 firing when in the Off position. The switch is in-line with
286 the positive battery terminal.
287 </p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp31516112"></a>1.3.1. Using an External Active Switch Circuit</h4></div></div></div><p>
288 You can use an active switch circuit, such as the
289 Featherweight Magnetic Switch, with any Altus Metrum
290 flight computer. These require three connections, one to
291 the battery, one to the positive power input on the flight
292 computer and one to ground. Find instructions on how to
293 hook these up for each flight computer below. The follow
294 the instructions that come with your active switch to
296 </p></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp31517952"></a>1.4. Using a Separate Pyro Battery</h3></div></div></div><p>
297 As mentioned above in the section on hooking up pyro
298 charges, one lead for each of the pyro charges is connected
299 through the power switch directly to the positive battery
300 terminal. The other lead is connected to the pyro circuit,
301 which connects it to the negative battery terminal when the
302 pyro circuit is fired. The pyro circuit on all of the flight
303 computers is designed to handle up to 16V.
305 To use a separate pyro battery, connect the negative pyro
306 battery terminal to the flight computer ground terminal,
307 the positive battery terminal to the igniter and the other
308 igniter lead to the negative pyro terminal on the flight
309 computer. When the pyro channel fires, it will complete the
310 circuit between the negative pyro terminal and the ground
311 terminal, firing the igniter. Specific instructions on how
312 to hook this up will be found in each section below.
313 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp36999216"></a>1.5. Using a Different Kind of Battery</h3></div></div></div><p>
314 EasyMini and TeleMini v2 are designed to use either a
315 lithium polymer battery or any other battery producing
316 between 4 and 12 volts, such as a rectangular 9V
317 battery. TeleMega, EasyMega and TeleMetrum are not designed for this,
318 and must only be powered by a lithium polymer battery. Find
319 instructions on how to use other batteries in the EasyMini
320 and TeleMini sections below.
321 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp34636960"></a>2. Specifications</h2></div></div></div><p>
322 Here's the full set of Altus Metrum products, both in
323 production and retired.
324 </p><div class="table"><a name="idp33882000"></a><p class="title"><b>Table 4.1. Altus Metrum Electronics</b></p><div class="table-contents"><table summary="Altus Metrum Electronics" border="1"><colgroup><col align="center" class="Device"><col align="center" class="Barometer"><col align="center" class="Z-axis accelerometer"><col align="center" class="GPS"><col align="center" class="3D sensors"><col align="center" class="Storage"><col align="center" class="RF"><col align="center" class="Battery"></colgroup><thead><tr><th align="center">Device</th><th align="center">Barometer</th><th align="center">Z-axis accelerometer</th><th align="center">GPS</th><th align="center">3D sensors</th><th align="center">Storage</th><th align="center">RF Output</th><th align="center">Battery</th></tr></thead><tbody><tr><td align="center">TeleMetrum v1.0</td><td align="center"><p>MP3H6115 10km (33k')</p></td><td align="center"><p>MMA2202 50g</p></td><td align="center">SkyTraq</td><td align="center">-</td><td align="center">1MB</td><td align="center">10mW</td><td align="center">3.7V</td></tr><tr><td align="center">TeleMetrum v1.1</td><td align="center"><p>MP3H6115 10km (33k')</p></td><td align="center"><p>MMA2202 50g</p></td><td align="center">SkyTraq</td><td align="center">-</td><td align="center">2MB</td><td align="center">10mW</td><td align="center">3.7V</td></tr><tr><td align="center">TeleMetrum v1.2</td><td align="center"><p>MP3H6115 10km (33k')</p></td><td align="center"><p>ADXL78 70g</p></td><td align="center">SkyTraq</td><td align="center">-</td><td align="center">2MB</td><td align="center">10mW</td><td align="center">3.7V</td></tr><tr><td align="center">TeleMetrum v2.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center"><p>MMA6555 102g</p></td><td align="center">uBlox Max-7Q</td><td align="center">-</td><td align="center">8MB</td><td align="center">40mW</td><td align="center">3.7V</td></tr><tr><td align="center"><p>TeleMini v1.0</p></td><td align="center"><p>MP3H6115 10km (33k')</p></td><td align="center">-</td><td align="center">-</td><td align="center">-</td><td align="center">5kB</td><td align="center">10mW</td><td align="center">3.7V</td></tr><tr><td align="center">TeleMini v2.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center">-</td><td align="center">-</td><td align="center">-</td><td align="center">1MB</td><td align="center">10mW</td><td align="center">3.7-12V</td></tr><tr><td align="center">EasyMini v1.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center">-</td><td align="center">-</td><td align="center">-</td><td align="center">1MB</td><td align="center">-</td><td align="center">3.7-12V</td></tr><tr><td align="center">TeleMega v1.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center"><p>MMA6555 102g</p></td><td align="center">uBlox Max-7Q</td><td align="center"><p>MPU6000 HMC5883</p></td><td align="center">8MB</td><td align="center">40mW</td><td align="center">3.7V</td></tr><tr><td align="center">EasyMega v1.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center"><p>MMA6555 102g</p></td><td align="center">-</td><td align="center"><p>MPU6000 HMC5883</p></td><td align="center">8MB</td><td align="center">-</td><td align="center">3.7V</td></tr></tbody></table></div></div><br class="table-break"><div class="table"><a name="idp37049568"></a><p class="title"><b>Table 4.2. Altus Metrum Boards</b></p><div class="table-contents"><table summary="Altus Metrum Boards" border="1"><colgroup><col align="center" class="Device"><col align="center" class="Connectors"><col align="center" class="Screw Terminals"><col align="center" class="Width"><col align="center" class="Length"><col align="center" class="Tube Size"></colgroup><thead><tr><th align="center">Device</th><th align="center">Connectors</th><th align="center">Screw Terminals</th><th align="center">Width</th><th align="center">Length</th><th align="center">Tube Size</th></tr></thead><tbody><tr><td align="center">TeleMetrum</td><td align="center"><p>
330 </p></td><td align="center"><p>Apogee pyro Main pyro Switch</p></td><td align="center">1 inch (2.54cm)</td><td align="center">2 ¾ inch (6.99cm)</td><td align="center">29mm coupler</td></tr><tr><td align="center"><p>TeleMini v1.0</p></td><td align="center"><p>
334 </p></td><td align="center"><p>
337 </p></td><td align="center">½ inch (1.27cm)</td><td align="center">1½ inch (3.81cm)</td><td align="center">18mm coupler</td></tr><tr><td align="center">TeleMini v2.0</td><td align="center"><p>
342 </p></td><td align="center"><p>
347 </p></td><td align="center">0.8 inch (2.03cm)</td><td align="center">1½ inch (3.81cm)</td><td align="center">24mm coupler</td></tr><tr><td align="center">EasyMini</td><td align="center"><p>
351 </p></td><td align="center"><p>
356 </p></td><td align="center">0.8 inch (2.03cm)</td><td align="center">1½ inch (3.81cm)</td><td align="center">24mm coupler</td></tr><tr><td align="center">TeleMega</td><td align="center"><p>
362 </p></td><td align="center"><p>
368 </p></td><td align="center">1¼ inch (3.18cm)</td><td align="center">3¼ inch (8.26cm)</td><td align="center">38mm coupler</td></tr><tr><td align="center">EasyMega</td><td align="center"><p>
373 </p></td><td align="center"><p>
379 </p></td><td align="center">1¼ inch (3.18cm)</td><td align="center">2¼ inch (5.62cm)</td><td align="center">38mm coupler</td></tr></tbody></table></div></div><br class="table-break"></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37090320"></a>3. TeleMetrum</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="telemetrum-v1.1-thside.jpg" width="495"></td></tr></table></div></div><p>
380 TeleMetrum is a 1 inch by 2¾ inch circuit board. It was designed to
381 fit inside coupler for 29mm air-frame tubing, but using it in a tube that
382 small in diameter may require some creativity in mounting and wiring
383 to succeed! The presence of an accelerometer means TeleMetrum should
384 be aligned along the flight axis of the airframe, and by default the ¼
385 wave UHF wire antenna should be on the nose-cone end of the board. The
386 antenna wire is about 7 inches long, and wiring for a power switch and
387 the e-matches for apogee and main ejection charges depart from the
388 fin can end of the board, meaning an ideal “simple” avionics
389 bay for TeleMetrum should have at least 10 inches of interior length.
390 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37095216"></a>3.1. TeleMetrum Screw Terminals</h3></div></div></div><p>
391 TeleMetrum has six screw terminals on the end of the board
392 opposite the telemetry antenna. Two are for the power
393 switch, and two each for the apogee and main igniter
394 circuits. Using the picture above and starting from the top,
395 the terminals are as follows:
396 </p><div class="table"><a name="idp37096528"></a><p class="title"><b>Table 4.3. TeleMetrum Screw Terminals</b></p><div class="table-contents"><table summary="TeleMetrum Screw Terminals" border="1"><colgroup><col align="center" class="Pin #"><col align="center" class="Pin Name"><col align="left" class="Description"></colgroup><thead><tr><th align="center">Terminal #</th><th align="center">Terminal Name</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">1</td><td align="center">Switch Output</td><td align="left">Switch connection to flight computer</td></tr><tr><td align="center">2</td><td align="center">Switch Input</td><td align="left">Switch connection to positive battery terminal</td></tr><tr><td align="center">3</td><td align="center">Main +</td><td align="left">Main pyro channel common connection to battery +</td></tr><tr><td align="center">4</td><td align="center">Main -</td><td align="left">Main pyro channel connection to pyro circuit</td></tr><tr><td align="center">5</td><td align="center">Apogee +</td><td align="left">Apogee pyro channel common connection to battery +</td></tr><tr><td align="center">6</td><td align="center">Apogee -</td><td align="left">Apogee pyro channel connection to pyro circuit</td></tr></tbody></table></div></div><br class="table-break"></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37114432"></a>3.2. Using a Separate Pyro Battery with TeleMetrum</h3></div></div></div><p>
397 As described above, using an external pyro battery involves
398 connecting the negative battery terminal to the flight
399 computer ground, connecting the positive battery terminal to
400 one of the igniter leads and connecting the other igniter
401 lead to the per-channel pyro circuit connection.
403 To connect the negative battery terminal to the TeleMetrum
404 ground, insert a small piece of wire, 24 to 28 gauge
405 stranded, into the GND hole just above the screw terminal
406 strip and solder it in place.
408 Connecting the positive battery terminal to the pyro
409 charges must be done separate from TeleMetrum, by soldering
410 them together or using some other connector.
412 The other lead from each pyro charge is then inserted into
413 the appropriate per-pyro channel screw terminal (terminal 4 for the
414 Main charge, terminal 6 for the Apogee charge).
415 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37117680"></a>3.3. Using an Active Switch with TeleMetrum</h3></div></div></div><p>
416 As explained above, an external active switch requires three
417 connections, one to the positive battery terminal, one to
418 the flight computer positive input and one to ground.
420 The positive battery terminal is available on screw terminal
421 2, the positive flight computer input is on terminal 1. To
422 hook a lead to ground, solder a piece of wire, 24 to 28
423 gauge stranded, to the GND hole just above terminal 1.
424 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37119808"></a>4. TeleMini v1.0</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="telemini-v1-top.jpg" width="495"></td></tr></table></div></div><p>
425 TeleMini v1.0 is ½ inches by 1½ inches. It was
426 designed to fit inside an 18mm air-frame tube, but using it in
427 a tube that small in diameter may require some creativity in
428 mounting and wiring to succeed! Since there is no
429 accelerometer, TeleMini can be mounted in any convenient
430 orientation. The default ¼ wave UHF wire antenna attached to
431 the center of one end of the board is about 7 inches long. Two
432 wires for the power switch are connected to holes in the
433 middle of the board. Screw terminals for the e-matches for
434 apogee and main ejection charges depart from the other end of
435 the board, meaning an ideal “simple” avionics bay for TeleMini
436 should have at least 9 inches of interior length.
437 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37124704"></a>4.1. TeleMini v1.0 Screw Terminals</h3></div></div></div><p>
438 TeleMini v1.0 has four screw terminals on the end of the
439 board opposite the telemetry antenna. Two are for the apogee
440 and two are for main igniter circuits. There are also wires
441 soldered to the board for the power switch. Using the
442 picture above and starting from the top for the terminals
443 and from the left for the power switch wires, the
444 connections are as follows:
445 </p><div class="table"><a name="idp37126144"></a><p class="title"><b>Table 4.4. TeleMini v1.0 Connections</b></p><div class="table-contents"><table summary="TeleMini v1.0 Connections" border="1"><colgroup><col align="center" class="Pin #"><col align="center" class="Pin Name"><col align="left" class="Description"></colgroup><thead><tr><th align="center">Terminal #</th><th align="center">Terminal Name</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">1</td><td align="center">Apogee -</td><td align="left">Apogee pyro channel connection to pyro circuit</td></tr><tr><td align="center">2</td><td align="center">Apogee +</td><td align="left">Apogee pyro channel common connection to battery +</td></tr><tr><td align="center">3</td><td align="center">Main -</td><td align="left">Main pyro channel connection to pyro circuit</td></tr><tr><td align="center">4</td><td align="center">Main +</td><td align="left">Main pyro channel common connection to battery +</td></tr><tr><td align="center">Left</td><td align="center">Switch Output</td><td align="left">Switch connection to flight computer</td></tr><tr><td align="center">Right</td><td align="center">Switch Input</td><td align="left">Switch connection to positive battery terminal</td></tr></tbody></table></div></div><br class="table-break"></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37144048"></a>4.2. Using a Separate Pyro Battery with TeleMini v1.0</h3></div></div></div><p>
446 As described above, using an external pyro battery involves
447 connecting the negative battery terminal to the flight
448 computer ground, connecting the positive battery terminal to
449 one of the igniter leads and connecting the other igniter
450 lead to the per-channel pyro circuit connection. Because
451 there is no solid ground connection to use on TeleMini, this
454 The only available ground connection on TeleMini v1.0 are
455 the two mounting holes next to the telemetry
456 antenna. Somehow connect a small piece of wire to one of
457 those holes and hook it to the negative pyro battery terminal.
459 Connecting the positive battery terminal to the pyro
460 charges must be done separate from TeleMini v1.0, by soldering
461 them together or using some other connector.
463 The other lead from each pyro charge is then inserted into
464 the appropriate per-pyro channel screw terminal (terminal 3 for the
465 Main charge, terminal 1 for the Apogee charge).
466 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37147424"></a>4.3. Using an Active Switch with TeleMini v1.0</h3></div></div></div><p>
467 As explained above, an external active switch requires three
468 connections, one to the positive battery terminal, one to
469 the flight computer positive input and one to ground. Again,
470 because TeleMini doesn't have any good ground connection,
471 this is not recommended.
473 The positive battery terminal is available on the Right
474 power switch wire, the positive flight computer input is on
475 the left power switch wire. Hook a lead to either of the
476 mounting holes for a ground connection.
477 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37149632"></a>5. TeleMini v2.0</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="telemini-v2-top.jpg" width="495"></td></tr></table></div></div><p>
478 TeleMini v2.0 is 0.8 inches by 1½ inches. It adds more
479 on-board data logging memory, a built-in USB connector and
480 screw terminals for the battery and power switch. The larger
481 board fits in a 24mm coupler. There's also a battery connector
482 for a LiPo battery if you want to use one of those.
483 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37153648"></a>5.1. TeleMini v2.0 Screw Terminals</h3></div></div></div><p>
484 TeleMini v2.0 has two sets of four screw terminals on the end of the
485 board opposite the telemetry antenna. Using the picture
486 above, the top four have connections for the main pyro
487 circuit and an external battery and the bottom four have
488 connections for the apogee pyro circuit and the power
489 switch. Counting from the left, the connections are as follows:
490 </p><div class="table"><a name="idp37155056"></a><p class="title"><b>Table 4.5. TeleMini v2.0 Connections</b></p><div class="table-contents"><table summary="TeleMini v2.0 Connections" border="1"><colgroup><col align="center" class="Pin #"><col align="center" class="Pin Name"><col align="left" class="Description"></colgroup><thead><tr><th align="center">Terminal #</th><th align="center">Terminal Name</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">Top 1</td><td align="center">Main -</td><td align="left">Main pyro channel connection to pyro circuit</td></tr><tr><td align="center">Top 2</td><td align="center">Main +</td><td align="left">Main pyro channel common connection to battery +</td></tr><tr><td align="center">Top 3</td><td align="center">Battery +</td><td align="left">Positive external battery terminal</td></tr><tr><td align="center">Top 4</td><td align="center">Battery -</td><td align="left">Negative external battery terminal</td></tr><tr><td align="center">Bottom 1</td><td align="center">Apogee -</td><td align="left">Apogee pyro channel connection to pyro circuit</td></tr><tr><td align="center">Bottom 2</td><td align="center">Apogee +</td><td align="left">Apogee pyro channel common connection to
491 battery +</td></tr><tr><td align="center">Bottom 3</td><td align="center">Switch Output</td><td align="left">Switch connection to flight computer</td></tr><tr><td align="center">Bottom 4</td><td align="center">Switch Input</td><td align="left">Switch connection to positive battery terminal</td></tr></tbody></table></div></div><br class="table-break"></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37176032"></a>5.2. Using a Separate Pyro Battery with TeleMini v2.0</h3></div></div></div><p>
492 As described above, using an external pyro battery involves
493 connecting the negative battery terminal to the flight
494 computer ground, connecting the positive battery terminal to
495 one of the igniter leads and connecting the other igniter
496 lead to the per-channel pyro circuit connection.
498 To connect the negative pyro battery terminal to TeleMini
499 ground, connect it to the negative external battery
500 connection, top terminal 4.
502 Connecting the positive battery terminal to the pyro
503 charges must be done separate from TeleMini v2.0, by soldering
504 them together or using some other connector.
506 The other lead from each pyro charge is then inserted into
507 the appropriate per-pyro channel screw terminal (top
508 terminal 1 for the Main charge, bottom terminal 1 for the
510 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37179232"></a>5.3. Using an Active Switch with TeleMini v2.0</h3></div></div></div><p>
511 As explained above, an external active switch requires three
512 connections, one to the positive battery terminal, one to
513 the flight computer positive input and one to ground. Use
514 the negative external battery connection, top terminal 4 for
517 The positive battery terminal is available on bottom
518 terminal 4, the positive flight computer input is on the
520 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37181328"></a>6. EasyMini</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="easymini-top.jpg" width="495"></td></tr></table></div></div><p>
521 EasyMini is built on a 0.8 inch by 1½ inch circuit board. It's
522 designed to fit in a 24mm coupler tube. The connectors and
523 screw terminals match TeleMini v2.0, so you can easily swap between
524 EasyMini and TeleMini.
525 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37185184"></a>6.1. EasyMini Screw Terminals</h3></div></div></div><p>
526 EasyMini has two sets of four screw terminals on the end of the
527 board opposite the telemetry antenna. Using the picture
528 above, the top four have connections for the main pyro
529 circuit and an external battery and the bottom four have
530 connections for the apogee pyro circuit and the power
531 switch. Counting from the left, the connections are as follows:
532 </p><div class="table"><a name="idp37186592"></a><p class="title"><b>Table 4.6. EasyMini Connections</b></p><div class="table-contents"><table summary="EasyMini Connections" border="1"><colgroup><col align="center" class="Pin #"><col align="center" class="Pin Name"><col align="left" class="Description"></colgroup><thead><tr><th align="center">Terminal #</th><th align="center">Terminal Name</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">Top 1</td><td align="center">Main -</td><td align="left">Main pyro channel connection to pyro circuit</td></tr><tr><td align="center">Top 2</td><td align="center">Main +</td><td align="left">Main pyro channel common connection to battery +</td></tr><tr><td align="center">Top 3</td><td align="center">Battery +</td><td align="left">Positive external battery terminal</td></tr><tr><td align="center">Top 4</td><td align="center">Battery -</td><td align="left">Negative external battery terminal</td></tr><tr><td align="center">Bottom 1</td><td align="center">Apogee -</td><td align="left">Apogee pyro channel connection to pyro circuit</td></tr><tr><td align="center">Bottom 2</td><td align="center">Apogee +</td><td align="left">Apogee pyro channel common connection to
533 battery +</td></tr><tr><td align="center">Bottom 3</td><td align="center">Switch Output</td><td align="left">Switch connection to flight computer</td></tr><tr><td align="center">Bottom 4</td><td align="center">Switch Input</td><td align="left">Switch connection to positive battery terminal</td></tr></tbody></table></div></div><br class="table-break"></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37207568"></a>6.2. Using a Separate Pyro Battery with EasyMini</h3></div></div></div><p>
534 As described above, using an external pyro battery involves
535 connecting the negative battery terminal to the flight
536 computer ground, connecting the positive battery terminal to
537 one of the igniter leads and connecting the other igniter
538 lead to the per-channel pyro circuit connection.
540 To connect the negative pyro battery terminal to TeleMini
541 ground, connect it to the negative external battery
542 connection, top terminal 4.
544 Connecting the positive battery terminal to the pyro
545 charges must be done separate from EasyMini, by soldering
546 them together or using some other connector.
548 The other lead from each pyro charge is then inserted into
549 the appropriate per-pyro channel screw terminal (top
550 terminal 1 for the Main charge, bottom terminal 1 for the
552 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37210752"></a>6.3. Using an Active Switch with EasyMini</h3></div></div></div><p>
553 As explained above, an external active switch requires three
554 connections, one to the positive battery terminal, one to
555 the flight computer positive input and one to ground. Use
556 the negative external battery connection, top terminal 4 for
559 The positive battery terminal is available on bottom
560 terminal 4, the positive flight computer input is on the
562 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37212848"></a>7. TeleMega</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="telemega-v1.0-top.jpg" width="495"></td></tr></table></div></div><p>
563 TeleMega is a 1¼ inch by 3¼ inch circuit board. It was
564 designed to easily fit in a 38mm coupler. Like TeleMetrum,
565 TeleMega has an accelerometer and so it must be mounted so that
566 the board is aligned with the flight axis. It can be mounted
567 either antenna up or down.
568 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37216816"></a>7.1. TeleMega Screw Terminals</h3></div></div></div><p>
569 TeleMega has two sets of nine screw terminals on the end of
570 the board opposite the telemetry antenna. They are as follows:
571 </p><div class="table"><a name="idp37217984"></a><p class="title"><b>Table 4.7. TeleMega Screw Terminals</b></p><div class="table-contents"><table summary="TeleMega Screw Terminals" border="1"><colgroup><col align="center" class="Pin #"><col align="center" class="Pin Name"><col align="left" class="Description"></colgroup><thead><tr><th align="center">Terminal #</th><th align="center">Terminal Name</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">Top 1</td><td align="center">Switch Input</td><td align="left">Switch connection to positive battery terminal</td></tr><tr><td align="center">Top 2</td><td align="center">Switch Output</td><td align="left">Switch connection to flight computer</td></tr><tr><td align="center">Top 3</td><td align="center">GND</td><td align="left">Ground connection for use with external active switch</td></tr><tr><td align="center">Top 4</td><td align="center">Main -</td><td align="left">Main pyro channel connection to pyro circuit</td></tr><tr><td align="center">Top 5</td><td align="center">Main +</td><td align="left">Main pyro channel common connection to battery +</td></tr><tr><td align="center">Top 6</td><td align="center">Apogee -</td><td align="left">Apogee pyro channel connection to pyro circuit</td></tr><tr><td align="center">Top 7</td><td align="center">Apogee +</td><td align="left">Apogee pyro channel common connection to battery +</td></tr><tr><td align="center">Top 8</td><td align="center">D -</td><td align="left">D pyro channel connection to pyro circuit</td></tr><tr><td align="center">Top 9</td><td align="center">D +</td><td align="left">D pyro channel common connection to battery +</td></tr><tr><td align="center">Bottom 1</td><td align="center">GND</td><td align="left">Ground connection for negative pyro battery terminal</td></tr><tr><td align="center">Bottom 2</td><td align="center">Pyro</td><td align="left">Positive pyro battery terminal</td></tr><tr><td align="center">Bottom 3</td><td align="center">Lipo</td><td align="left">
572 Power switch output. Use to connect main battery to
574 </td></tr><tr><td align="center">Bottom 4</td><td align="center">A -</td><td align="left">A pyro channel connection to pyro circuit</td></tr><tr><td align="center">Bottom 5</td><td align="center">A +</td><td align="left">A pyro channel common connection to battery +</td></tr><tr><td align="center">Bottom 6</td><td align="center">B -</td><td align="left">B pyro channel connection to pyro circuit</td></tr><tr><td align="center">Bottom 7</td><td align="center">B +</td><td align="left">B pyro channel common connection to battery +</td></tr><tr><td align="center">Bottom 8</td><td align="center">C -</td><td align="left">C pyro channel connection to pyro circuit</td></tr><tr><td align="center">Bottom 9</td><td align="center">C +</td><td align="left">C pyro channel common connection to battery +</td></tr></tbody></table></div></div><br class="table-break"></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37254320"></a>7.2. Using a Separate Pyro Battery with TeleMega</h3></div></div></div><p>
575 TeleMega provides explicit support for an external pyro
576 battery. All that is required is to remove the jumper
577 between the lipo terminal (Bottom 3) and the pyro terminal
578 (Bottom 2). Then hook the negative pyro battery terminal to ground
579 (Bottom 1) and the positive pyro battery to the pyro battery
580 input (Bottom 2). You can then use the existing pyro screw
581 terminals to hook up all of the pyro charges.
582 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37255920"></a>7.3. Using Only One Battery With TeleMega</h3></div></div></div><p>
583 Because TeleMega has built-in support for a separate pyro
584 battery, if you want to fly with just one battery running
585 both the computer and firing the charges, you need to
586 connect the flight computer battery to the pyro
587 circuit. TeleMega has two screw terminals for this—hook a
588 wire from the Lipo terminal (Bottom 3) to the Pyro terminal
590 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37257840"></a>7.4. Using an Active Switch with TeleMega</h3></div></div></div><p>
591 As explained above, an external active switch requires three
592 connections, one to the positive battery terminal, one to
593 the flight computer positive input and one to ground.
595 The positive battery terminal is available on Top terminal
596 1, the positive flight computer input is on Top terminal
597 2. Ground is on Top terminal 3.
598 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37259888"></a>8. EasyMega</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="405"><tr><td><img src="easymega-v1.0-top.jpg" width="405"></td></tr></table></div></div><p>
599 EasyMega is a 1¼ inch by 2¼ inch circuit board. It was
600 designed to easily fit in a 38mm coupler. Like TeleMetrum,
601 EasyMega has an accelerometer and so it must be mounted so that
602 the board is aligned with the flight axis. It can be mounted
603 either antenna up or down.
604 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37263856"></a>8.1. EasyMega Screw Terminals</h3></div></div></div><p>
605 EasyMega has two sets of nine screw terminals on the end of
606 the board opposite the telemetry antenna. They are as follows:
607 </p><div class="table"><a name="idp37265024"></a><p class="title"><b>Table 4.8. EasyMega Screw Terminals</b></p><div class="table-contents"><table summary="EasyMega Screw Terminals" border="1"><colgroup><col align="center" class="Pin #"><col align="center" class="Pin Name"><col align="left" class="Description"></colgroup><thead><tr><th align="center">Terminal #</th><th align="center">Terminal Name</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">Top 1</td><td align="center">Switch Input</td><td align="left">Switch connection to positive battery terminal</td></tr><tr><td align="center">Top 2</td><td align="center">Switch Output</td><td align="left">Switch connection to flight computer</td></tr><tr><td align="center">Top 3</td><td align="center">GND</td><td align="left">Ground connection for use with external active switch</td></tr><tr><td align="center">Top 4</td><td align="center">Main -</td><td align="left">Main pyro channel connection to pyro circuit</td></tr><tr><td align="center">Top 5</td><td align="center">Main +</td><td align="left">Main pyro channel common connection to battery +</td></tr><tr><td align="center">Top 6</td><td align="center">Apogee -</td><td align="left">Apogee pyro channel connection to pyro circuit</td></tr><tr><td align="center">Top 7</td><td align="center">Apogee +</td><td align="left">Apogee pyro channel common connection to battery +</td></tr><tr><td align="center">Top 8</td><td align="center">D -</td><td align="left">D pyro channel connection to pyro circuit</td></tr><tr><td align="center">Top 9</td><td align="center">D +</td><td align="left">D pyro channel common connection to battery +</td></tr><tr><td align="center">Bottom 1</td><td align="center">GND</td><td align="left">Ground connection for negative pyro battery terminal</td></tr><tr><td align="center">Bottom 2</td><td align="center">Pyro</td><td align="left">Positive pyro battery terminal</td></tr><tr><td align="center">Bottom 3</td><td align="center">Lipo</td><td align="left">
608 Power switch output. Use to connect main battery to
610 </td></tr><tr><td align="center">Bottom 4</td><td align="center">A -</td><td align="left">A pyro channel connection to pyro circuit</td></tr><tr><td align="center">Bottom 5</td><td align="center">A +</td><td align="left">A pyro channel common connection to battery +</td></tr><tr><td align="center">Bottom 6</td><td align="center">B -</td><td align="left">B pyro channel connection to pyro circuit</td></tr><tr><td align="center">Bottom 7</td><td align="center">B +</td><td align="left">B pyro channel common connection to battery +</td></tr><tr><td align="center">Bottom 8</td><td align="center">C -</td><td align="left">C pyro channel connection to pyro circuit</td></tr><tr><td align="center">Bottom 9</td><td align="center">C +</td><td align="left">C pyro channel common connection to battery +</td></tr></tbody></table></div></div><br class="table-break"></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37301456"></a>8.2. Using a Separate Pyro Battery with EasyMega</h3></div></div></div><p>
611 EasyMega provides explicit support for an external pyro
612 battery. All that is required is to remove the jumper
613 between the lipo terminal (Bottom 3) and the pyro terminal
614 (Bottom 2). Then hook the negative pyro battery terminal to ground
615 (Bottom 1) and the positive pyro battery to the pyro battery
616 input (Bottom 2). You can then use the existing pyro screw
617 terminals to hook up all of the pyro charges.
618 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37303056"></a>8.3. Using Only One Battery With EasyMega</h3></div></div></div><p>
619 Because EasyMega has built-in support for a separate pyro
620 battery, if you want to fly with just one battery running
621 both the computer and firing the charges, you need to
622 connect the flight computer battery to the pyro
623 circuit. EasyMega has two screw terminals for this—hook a
624 wire from the Lipo terminal (Bottom 3) to the Pyro terminal
626 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37304976"></a>8.4. Using an Active Switch with EasyMega</h3></div></div></div><p>
627 As explained above, an external active switch requires three
628 connections, one to the positive battery terminal, one to
629 the flight computer positive input and one to ground.
631 The positive battery terminal is available on Top terminal
632 1, the positive flight computer input is on Top terminal
633 2. Ground is on Top terminal 3.
634 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37307024"></a>9. Flight Data Recording</h2></div></div></div><p>
635 Each flight computer logs data at 100 samples per second
636 during ascent and 10 samples per second during descent, except
637 for TeleMini v1.0, which records ascent at 10 samples per
638 second and descent at 1 sample per second. Data are logged to
639 an on-board flash memory part, which can be partitioned into
640 several equal-sized blocks, one for each flight.
641 </p><div class="table"><a name="idp37308432"></a><p class="title"><b>Table 4.9. Data Storage on Altus Metrum altimeters</b></p><div class="table-contents"><table summary="Data Storage on Altus Metrum altimeters" border="1"><colgroup><col align="center" class="Device"><col align="center" class="Bytes per sample"><col align="center" class="Total storage"><col align="center" class="Minutes of full-rate"></colgroup><thead><tr><th align="center">Device</th><th align="center">Bytes per Sample</th><th align="center">Total Storage</th><th align="center">Minutes at Full Rate</th></tr></thead><tbody><tr><td align="center">TeleMetrum v1.0</td><td align="center">8</td><td align="center">1MB</td><td align="center">20</td></tr><tr><td align="center">TeleMetrum v1.1 v1.2</td><td align="center">8</td><td align="center">2MB</td><td align="center">40</td></tr><tr><td align="center">TeleMetrum v2.0</td><td align="center">16</td><td align="center">8MB</td><td align="center">80</td></tr><tr><td align="center">TeleMini v1.0</td><td align="center">2</td><td align="center">5kB</td><td align="center">4</td></tr><tr><td align="center">TeleMini v2.0</td><td align="center">16</td><td align="center">1MB</td><td align="center">10</td></tr><tr><td align="center">EasyMini</td><td align="center">16</td><td align="center">1MB</td><td align="center">10</td></tr><tr><td align="center">TeleMega</td><td align="center">32</td><td align="center">8MB</td><td align="center">40</td></tr><tr><td align="center">EasyMega</td><td align="center">32</td><td align="center">8MB</td><td align="center">40</td></tr></tbody></table></div></div><br class="table-break"><p>
642 The on-board flash is partitioned into separate flight logs,
643 each of a fixed maximum size. Increase the maximum size of
644 each log and you reduce the number of flights that can be
645 stored. Decrease the size and you can store more flights.
647 Configuration data is also stored in the flash memory on
648 TeleMetrum v1.x, TeleMini and EasyMini. This consumes 64kB
649 of flash space. This configuration space is not available
650 for storing flight log data. TeleMetrum v2.0, TeleMega and EasyMega
651 store configuration data in a bit of eeprom available within
652 the processor chip, leaving that space available in flash for
655 To compute the amount of space needed for a single flight, you
656 can multiply the expected ascent time (in seconds) by 100
657 times bytes-per-sample, multiply the expected descent time (in
658 seconds) by 10 times the bytes per sample and add the two
659 together. That will slightly under-estimate the storage (in
660 bytes) needed for the flight. For instance, a TeleMetrum v2.0 flight spending
661 20 seconds in ascent and 150 seconds in descent will take
662 about (20 * 1600) + (150 * 160) = 56000 bytes of storage. You
663 could store dozens of these flights in the on-board flash.
665 The default size allows for several flights on each flight
666 computer, except for TeleMini v1.0, which only holds data for a
667 single flight. You can adjust the size.
669 Altus Metrum flight computers will not overwrite existing
670 flight data, so be sure to download flight data and erase it
671 from the flight computer before it fills up. The flight
672 computer will still successfully control the flight even if it
673 cannot log data, so the only thing you will lose is the data.
674 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37337792"></a>10. Installation</h2></div></div></div><p>
675 A typical installation involves attaching
676 only a suitable battery, a single pole switch for
677 power on/off, and two pairs of wires connecting e-matches for the
678 apogee and main ejection charges. All Altus Metrum products are
679 designed for use with single-cell batteries with 3.7 volts
680 nominal. TeleMini v2.0 and EasyMini may also be used with other
681 batteries as long as they supply between 4 and 12 volts.
683 The battery connectors are a standard 2-pin JST connector and
684 match batteries sold by Spark Fun. These batteries are
685 single-cell Lithium Polymer batteries that nominally provide 3.7
686 volts. Other vendors sell similar batteries for RC aircraft
687 using mating connectors, however the polarity for those is
688 generally reversed from the batteries used by Altus Metrum
689 products. In particular, the Tenergy batteries supplied for use
690 in Featherweight flight computers are not compatible with Altus
691 Metrum flight computers or battery chargers. <span class="emphasis"><em>Check
692 polarity and voltage before connecting any battery not purchased
693 from Altus Metrum or Spark Fun.</em></span>
695 By default, we use the unregulated output of the battery directly
696 to fire ejection charges. This works marvelously with standard
697 low-current e-matches like the J-Tek from MJG Technologies, and with
698 Quest Q2G2 igniters. However, if you want or need to use a separate
699 pyro battery, check out the “External Pyro Battery” section in this
700 manual for instructions on how to wire that up. The altimeters are
701 designed to work with an external pyro battery of no more than 15 volts.
703 Ejection charges are wired directly to the screw terminal block
704 at the aft end of the altimeter. You'll need a very small straight
705 blade screwdriver for these screws, such as you might find in a
706 jeweler's screwdriver set.
708 Except for TeleMini v1.0, the flight computers also use the
709 screw terminal block for the power switch leads. On TeleMini v1.0,
710 the power switch leads are soldered directly to the board and
711 can be connected directly to a switch.
713 For most air-frames, the integrated antennas are more than
714 adequate. However, if you are installing in a carbon-fiber or
715 metal electronics bay which is opaque to RF signals, you may need to
716 use off-board external antennas instead. In this case, you can
717 replace the stock UHF antenna wire with an edge-launched SMA connector,
718 and, on TeleMetrum v1, you can unplug the integrated GPS
719 antenna and select an appropriate off-board GPS antenna with
720 cable terminating in a U.FL connector.
721 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp37344528"></a>Chapter 5. System Operation</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp37345168">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp37413664">2. GPS </a></span></dt><dt><span class="section"><a href="#idp37416448">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp37427744">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp37430496">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp37434496">6. APRS</a></span></dt><dt><span class="section"><a href="#idp37458816">7. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37460736">7.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp37462784">7.2. Callsign</a></span></dt><dt><span class="section"><a href="#idp37464320">7.3. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp37465616">7.4. Telemetry baud rate</a></span></dt><dt><span class="section"><a href="#idp37467184">7.5. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp37468656">7.6. APRS SSID</a></span></dt><dt><span class="section"><a href="#idp37470000">7.7. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp37472592">7.8. Apogee Lockout</a></span></dt><dt><span class="section"><a href="#idp37474320">7.9. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp37476016">7.10. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp37478160">7.11. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp37480272">7.12. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp37481968">7.13. Configurable Pyro Channels</a></span></dt></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37345168"></a>1. Firmware Modes </h2></div></div></div><p>
722 The AltOS firmware build for the altimeters has two
723 fundamental modes, “idle” and “flight”. Which of these modes
724 the firmware operates in is determined at start up time. For
725 TeleMetrum, TeleMega and EasyMega, which have accelerometers, the mode is
726 controlled by the orientation of the
727 rocket (well, actually the board, of course...) at the time
728 power is switched on. If the rocket is “nose up”, then
729 the flight computer assumes it's on a rail or rod being prepared for
730 launch, so the firmware chooses flight mode. However, if the
731 rocket is more or less horizontal, the firmware instead enters
732 idle mode. Since TeleMini v2.0 and EasyMini don't have an
733 accelerometer we can use to determine orientation, “idle” mode
734 is selected if the board is connected via USB to a computer,
735 otherwise the board enters “flight” mode. TeleMini v1.0
736 selects “idle” mode if it receives a command packet within the
737 first five seconds of operation.
739 At power on, the altimeter will beep out the battery voltage
740 to the nearest tenth of a volt. Each digit is represented by
741 a sequence of short “dit” beeps, with a pause between
742 digits. A zero digit is represented with one long “dah”
743 beep. Then there will be a short pause while the altimeter
744 completes initialization and self test, and decides which mode
747 Here's a short summary of all of the modes and the beeping (or
748 flashing, in the case of TeleMini v1) that accompanies each
749 mode. In the description of the beeping pattern, “dit” means a
750 short beep while "dah" means a long beep (three times as
751 long). “Brap” means a long dissonant tone.
752 </p><div class="table"><a name="idp37350528"></a><p class="title"><b>Table 5.1. AltOS Modes</b></p><div class="table-contents"><table summary="AltOS Modes" border="1"><colgroup><col align="center" class="Mode Name"><col align="center" class="Letter"><col align="center" class="Beeps"><col align="center" class="Description"></colgroup><thead><tr><th align="center">Mode Name</th><th align="center">Abbreviation</th><th align="center">Beeps</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">Startup</td><td align="center">S</td><td align="center">battery voltage in decivolts</td><td align="center">
754 Calibrating sensors, detecting orientation.
756 </td></tr><tr><td align="center">Idle</td><td align="center">I</td><td align="center">dit dit</td><td align="center">
758 Ready to accept commands over USB or radio link.
760 </td></tr><tr><td align="center">Pad</td><td align="center">P</td><td align="center">dit dah dah dit</td><td align="center">
762 Waiting for launch. Not listening for commands.
764 </td></tr><tr><td align="center">Boost</td><td align="center">B</td><td align="center">dah dit dit dit</td><td align="center">
766 Accelerating upwards.
768 </td></tr><tr><td align="center">Fast</td><td align="center">F</td><td align="center">dit dit dah dit</td><td align="center">
770 Decelerating, but moving faster than 200m/s.
772 </td></tr><tr><td align="center">Coast</td><td align="center">C</td><td align="center">dah dit dah dit</td><td align="center">
774 Decelerating, moving slower than 200m/s
776 </td></tr><tr><td align="center">Drogue</td><td align="center">D</td><td align="center">dah dit dit</td><td align="center">
778 Descending after apogee. Above main height.
780 </td></tr><tr><td align="center">Main</td><td align="center">M</td><td align="center">dah dah</td><td align="center">
782 Descending. Below main height.
784 </td></tr><tr><td align="center">Landed</td><td align="center">L</td><td align="center">dit dah dit dit</td><td align="center">
786 Stable altitude for at least ten seconds.
788 </td></tr><tr><td align="center">Sensor error</td><td align="center">X</td><td align="center">dah dit dit dah</td><td align="center">
790 Error detected during sensor calibration.
792 </td></tr></tbody></table></div></div><p><br class="table-break">
794 In flight or “pad” mode, the altimeter engages the flight
795 state machine, goes into transmit-only mode to send telemetry,
796 and waits for launch to be detected. Flight mode is indicated
797 by an “di-dah-dah-dit” (“P” for pad) on the beeper or lights,
798 followed by beeps or flashes indicating the state of the
799 pyrotechnic igniter continuity. One beep/flash indicates
800 apogee continuity, two beeps/flashes indicate main continuity,
801 three beeps/flashes indicate both apogee and main continuity,
802 and one longer “brap” sound which is made by rapidly
803 alternating between two tones indicates no continuity. For a
804 dual deploy flight, make sure you're getting three beeps or
805 flashes before launching! For apogee-only or motor eject
806 flights, do what makes sense.
808 If idle mode is entered, you will hear an audible “di-dit” or
809 see two short flashes (“I” for idle), and the flight state
810 machine is disengaged, thus no ejection charges will fire.
811 The altimeters also listen for the radio link when in idle
812 mode for requests sent via TeleDongle. Commands can be issued
813 in idle mode over either USB or the radio link
814 equivalently. TeleMini v1.0 only has the radio link. Idle
815 mode is useful for configuring the altimeter, for extracting
816 data from the on-board storage chip after flight, and for
817 ground testing pyro charges.
819 In “Idle” and “Pad” modes, once the mode indication
820 beeps/flashes and continuity indication has been sent, if
821 there is no space available to log the flight in on-board
822 memory, the flight computer will emit a warbling tone (much
823 slower than the “no continuity tone”)
825 Here's a summary of all of the “pad” and “idle” mode indications.
826 </p><div class="table"><a name="idp37387712"></a><p class="title"><b>Table 5.2. Pad/Idle Indications</b></p><div class="table-contents"><table summary="Pad/Idle Indications" border="1"><colgroup><col align="center" class="Name"><col align="center" class="Beeps"><col align="center" class="Description"></colgroup><thead><tr><th align="center">Name</th><th align="center">Beeps</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">Neither</td><td align="center">brap</td><td align="center">
828 No continuity detected on either apogee or main
831 </td></tr><tr><td align="center">Apogee</td><td align="center">dit</td><td align="center">
833 Continuity detected only on apogee igniter.
835 </td></tr><tr><td align="center">Main</td><td align="center">dit dit</td><td align="center">
837 Continuity detected only on main igniter.
839 </td></tr><tr><td align="center">Both</td><td align="center">dit dit dit</td><td align="center">
841 Continuity detected on both igniters.
843 </td></tr><tr><td align="center">Storage Full</td><td align="center">warble</td><td align="center">
845 On-board data logging storage is full. This will
846 not prevent the flight computer from safely
847 controlling the flight or transmitting telemetry
848 signals, but no record of the flight will be
849 stored in on-board flash.
851 </td></tr></tbody></table></div></div><p><br class="table-break">
853 Once landed, the flight computer will signal that by emitting
854 the “Landed” sound described above, after which it will beep
855 out the apogee height (in meters). Each digit is represented
856 by a sequence of short “dit” beeps, with a pause between
857 digits. A zero digit is represented with one long “dah”
858 beep. The flight computer will continue to report landed mode
859 and beep out the maximum height until turned off.
861 One “neat trick” of particular value when TeleMetrum, TeleMega
862 or EasyMega are used with
863 very large air-frames, is that you can power the board up while the
864 rocket is horizontal, such that it comes up in idle mode. Then you can
865 raise the air-frame to launch position, and issue a 'reset' command
866 via TeleDongle over the radio link to cause the altimeter to reboot and
867 come up in flight mode. This is much safer than standing on the top
868 step of a rickety step-ladder or hanging off the side of a launch
869 tower with a screw-driver trying to turn on your avionics before
872 TeleMini v1.0 is configured solely via the radio link. Of course, that
873 means you need to know the TeleMini radio configuration values
874 or you won't be able to communicate with it. For situations
875 when you don't have the radio configuration values, TeleMini v1.0
876 offers an 'emergency recovery' mode. In this mode, TeleMini is
877 configured as follows:
878 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
879 Sets the radio frequency to 434.550MHz
880 </p></li><li class="listitem"><p>
881 Sets the radio calibration back to the factory value.
882 </p></li><li class="listitem"><p>
883 Sets the callsign to N0CALL
884 </p></li><li class="listitem"><p>
885 Does not go to 'pad' mode after five seconds.
886 </p></li></ul></div><p>
888 To get into 'emergency recovery' mode, first find the row of
889 four small holes opposite the switch wiring. Using a short
890 piece of small gauge wire, connect the outer two holes
891 together, then power TeleMini up. Once the red LED is lit,
892 disconnect the wire and the board should signal that it's in
893 'idle' mode after the initial five second startup period.
894 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37413664"></a>2. GPS </h2></div></div></div><p>
895 TeleMetrum and TeleMega include a complete GPS receiver. A
896 complete explanation of how GPS works is beyond the scope of
897 this manual, but the bottom line is that the GPS receiver
898 needs to lock onto at least four satellites to obtain a solid
899 3 dimensional position fix and know what time it is.
901 The flight computers provide backup power to the GPS chip any time a
902 battery is connected. This allows the receiver to “warm start” on
903 the launch rail much faster than if every power-on were a GPS
904 “cold start”. In typical operations, powering up
905 on the flight line in idle mode while performing final air-frame
906 preparation will be sufficient to allow the GPS receiver to cold
907 start and acquire lock. Then the board can be powered down during
908 RSO review and installation on a launch rod or rail. When the board
909 is turned back on, the GPS system should lock very quickly, typically
910 long before igniter installation and return to the flight line are
912 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37416448"></a>3. Controlling An Altimeter Over The Radio Link</h2></div></div></div><p>
913 One of the unique features of the Altus Metrum system is the
914 ability to create a two way command link between TeleDongle
915 and an altimeter using the digital radio transceivers
916 built into each device. This allows you to interact with the
917 altimeter from afar, as if it were directly connected to the
920 Any operation which can be performed with a flight computer can
921 either be done with the device directly connected to the
922 computer via the USB cable, or through the radio
923 link. TeleMini v1.0 doesn't provide a USB connector and so it is
924 always communicated with over radio. Select the appropriate
925 TeleDongle device when the list of devices is presented and
926 AltosUI will interact with an altimeter over the radio link.
928 One oddity in the current interface is how AltosUI selects the
929 frequency for radio communications. Instead of providing
930 an interface to specifically configure the frequency, it uses
931 whatever frequency was most recently selected for the target
932 TeleDongle device in Monitor Flight mode. If you haven't ever
933 used that mode with the TeleDongle in question, select the
934 Monitor Flight button from the top level UI, and pick the
935 appropriate TeleDongle device. Once the flight monitoring
936 window is open, select the desired frequency and then close it
937 down again. All radio communications will now use that frequency.
938 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
939 Save Flight Data—Recover flight data from the rocket without
941 </p></li><li class="listitem"><p>
942 Configure altimeter apogee delays, main deploy heights
943 and additional pyro event conditions
944 to respond to changing launch conditions. You can also
945 'reboot' the altimeter. Use this to remotely enable the
946 flight computer by turning TeleMetrum or TeleMega on in “idle” mode,
947 then once the air-frame is oriented for launch, you can
948 reboot the altimeter and have it restart in pad mode
949 without having to climb the scary ladder.
950 </p></li><li class="listitem"><p>
951 Fire Igniters—Test your deployment charges without snaking
952 wires out through holes in the air-frame. Simply assemble the
953 rocket as if for flight with the apogee and main charges
954 loaded, then remotely command the altimeter to fire the
956 </p></li></ul></div><p>
957 Operation over the radio link for configuring an altimeter, ground
958 testing igniters, and so forth uses the same RF frequencies as flight
959 telemetry. To configure the desired TeleDongle frequency, select
960 the monitor flight tab, then use the frequency selector and
961 close the window before performing other desired radio operations.
963 The flight computers only enable radio commanding in 'idle' mode.
964 TeleMetrum and TeleMega use the accelerometer to detect which orientation they
965 start up in, so make sure you have the flight computer lying horizontally when you turn
966 it on. Otherwise, it will start in 'pad' mode ready for
967 flight, and will not be listening for command packets from TeleDongle.
969 TeleMini listens for a command packet for five seconds after
970 first being turned on, if it doesn't hear anything, it enters
971 'pad' mode, ready for flight and will no longer listen for
972 command packets. The easiest way to connect to TeleMini is to
973 initiate the command and select the TeleDongle device. At this
974 point, the TeleDongle will be attempting to communicate with
975 the TeleMini. Now turn TeleMini on, and it should immediately
976 start communicating with the TeleDongle and the desired
977 operation can be performed.
979 You can monitor the operation of the radio link by watching the
980 lights on the devices. The red LED will flash each time a packet
981 is transmitted, while the green LED will light up on TeleDongle when
982 it is waiting to receive a packet from the altimeter.
983 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37427744"></a>4. Ground Testing </h2></div></div></div><p>
984 An important aspect of preparing a rocket using electronic deployment
985 for flight is ground testing the recovery system. Thanks
986 to the bi-directional radio link central to the Altus Metrum system,
987 this can be accomplished in a TeleMega, TeleMetrum or TeleMini equipped rocket
988 with less work than you may be accustomed to with other systems. It
991 Just prep the rocket for flight, then power up the altimeter
992 in “idle” mode (placing air-frame horizontal for TeleMetrum or TeleMega, or
993 selecting the Configure Altimeter tab for TeleMini). This will cause
994 the firmware to go into “idle” mode, in which the normal flight
995 state machine is disabled and charges will not fire without
996 manual command. You can now command the altimeter to fire the apogee
997 or main charges from a safe distance using your computer and
998 TeleDongle and the Fire Igniter tab to complete ejection testing.
999 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37430496"></a>5. Radio Link </h2></div></div></div><p>
1000 Our flight computers all incorporate an RF transceiver, but
1001 it's not a full duplex system... each end can only be transmitting or
1002 receiving at any given moment. So we had to decide how to manage the
1005 By design, the altimeter firmware listens for the radio link when
1006 it's in “idle mode”, which
1007 allows us to use the radio link to configure the rocket, do things like
1008 ejection tests, and extract data after a flight without having to
1009 crack open the air-frame. However, when the board is in “flight
1010 mode”, the altimeter only
1011 transmits and doesn't listen at all. That's because we want to put
1012 ultimate priority on event detection and getting telemetry out of
1014 the radio in case the rocket crashes and we aren't able to extract
1017 We don't generally use a 'normal packet radio' mode like APRS
1018 because they're just too inefficient. The GFSK modulation we
1019 use is FSK with the base-band pulses passed through a Gaussian
1020 filter before they go into the modulator to limit the
1021 transmitted bandwidth. When combined with forward error
1022 correction and interleaving, this allows us to have a very
1023 robust 19.2 kilobit data link with only 10-40 milliwatts of
1024 transmit power, a whip antenna in the rocket, and a hand-held
1025 Yagi on the ground. We've had flights to above 21k feet AGL
1026 with great reception, and calculations suggest we should be
1027 good to well over 40k feet AGL with a 5-element yagi on the
1028 ground with our 10mW units and over 100k feet AGL with the
1029 40mW devices. We hope to fly boards to higher altitudes over
1030 time, and would of course appreciate customer feedback on
1031 performance in higher altitude flights!
1032 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37434496"></a>6. APRS</h2></div></div></div><p>
1033 TeleMetrum v2.0 and TeleMega can send APRS if desired, and the
1034 interval between APRS packets can be configured. As each APRS
1035 packet takes a full second to transmit, we recommend an
1036 interval of at least 5 seconds to avoid consuming too much
1037 battery power or radio channel bandwidth. You can configure
1038 the APRS interval using AltosUI; that process is described in
1039 the Configure Altimeter section of the AltosUI chapter.
1041 AltOS uses the APRS compressed position report data format,
1042 which provides for higher position precision and shorter
1043 packets than the original APRS format. It also includes
1044 altitude data, which is invaluable when tracking rockets. We
1045 haven't found a receiver which doesn't handle compressed
1046 positions, but it's just possible that you have one, so if you
1047 have an older device that can receive the raw packets but
1048 isn't displaying position information, it's possible that this
1051 APRS packets include an SSID (Secondary Station Identifier)
1052 field that allows one operator to have multiple
1053 transmitters. AltOS allows you to set this to a single digit
1054 from 0 to 9, allowing you to fly multiple transmitters at the
1055 same time while keeping the identify of each one separate in
1056 the receiver. By default, the SSID is set to the last digit of
1057 the device serial number.
1059 The APRS packet format includes a comment field that can have
1060 arbitrary text in it. AltOS uses this to send status
1061 information about the flight computer. It sends four fields as
1062 shown in the following table.
1063 </p><div class="table"><a name="idp37438304"></a><p class="title"><b>Table 5.3. Altus Metrum APRS Comments</b></p><div class="table-contents"><table summary="Altus Metrum APRS Comments" border="1"><colgroup><col align="center" class="Field"><col align="center" class="Example"><col align="center" class="Description"></colgroup><thead><tr><th align="center">Field</th><th align="center">Example</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">1</td><td align="center">L</td><td align="center">GPS Status U for unlocked, L for locked</td></tr><tr><td align="center">2</td><td align="center">6</td><td align="center">Number of Satellites in View</td></tr><tr><td align="center">3</td><td align="center">B4.0</td><td align="center">Altimeter Battery Voltage</td></tr><tr><td align="center">4</td><td align="center">A3.7</td><td align="center">Apogee Igniter Voltage</td></tr><tr><td align="center">5</td><td align="center">M3.7</td><td align="center">Main Igniter Voltage</td></tr><tr><td align="center">6</td><td align="center">1286</td><td align="center">Device Serial Number</td></tr></tbody></table></div></div><br class="table-break"><p>
1064 Here's an example of an APRS comment showing GPS lock with 6
1065 satellites in view, a primary battery at 4.0V, and
1066 apogee and main igniters both at 3.7V from device 1286.
1067 </p><pre class="screen">
1068 L6 B4.0 A3.7 M3.7 1286
1071 Make sure your primary battery is above 3.8V, any connected
1072 igniters are above 3.5V and GPS is locked with at least 5 or 6
1073 satellites in view before flying. If GPS is switching between
1074 L and U regularly, then it doesn't have a good lock and you
1075 should wait until it becomes stable.
1077 If the GPS receiver loses lock, the APRS data transmitted will
1078 contain the last position for which GPS lock was
1079 available. You can tell that this has happened by noticing
1080 that the GPS status character switches from 'L' to 'U'. Before
1081 GPS has locked, APRS will transmit zero for latitude,
1082 longitude and altitude.
1083 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37458816"></a>7. Configurable Parameters</h2></div></div></div><p>
1084 Configuring an Altus Metrum altimeter for flight is very
1085 simple. Even on our baro-only TeleMini and EasyMini boards,
1086 the use of a Kalman filter means there is no need to set a
1087 “mach delay”. The few configurable parameters can all be set
1088 using AltosUI over USB or or radio link via TeleDongle. Read
1089 the Configure Altimeter section in the AltosUI chapter below
1090 for more information.
1091 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37460736"></a>7.1. Radio Frequency</h3></div></div></div><p>
1092 Altus Metrum boards support radio frequencies in the 70cm
1093 band. By default, the configuration interface provides a
1094 list of 10 “standard” frequencies in 100kHz channels starting at
1095 434.550MHz. However, the firmware supports use of
1096 any 50kHz multiple within the 70cm band. At any given
1097 launch, we highly recommend coordinating when and by whom each
1098 frequency will be used to avoid interference. And of course, both
1099 altimeter and TeleDongle must be configured to the same
1100 frequency to successfully communicate with each other.
1101 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37462784"></a>7.2. Callsign</h3></div></div></div><p>
1102 This sets the callsign used for telemetry, APRS and the
1103 packet link. For telemetry and APRS, this is used to
1104 identify the device. For the packet link, the callsign must
1105 match that configured in AltosUI or the link will not
1106 work. This is to prevent accidental configuration of another
1107 Altus Metrum flight computer operating on the same frequency nearby.
1108 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37464320"></a>7.3. Telemetry/RDF/APRS Enable</h3></div></div></div><p>
1109 You can completely disable the radio while in flight, if
1110 necessary. This doesn't disable the packet link in idle
1112 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37465616"></a>7.4. Telemetry baud rate</h3></div></div></div><p>
1113 This sets the modulation bit rate for data transmission for
1114 both telemetry and packet link mode. Lower bit
1115 rates will increase range while reducing the amount of data
1116 that can be sent and increasing battery consumption. All
1117 telemetry is done using a rate 1/2 constraint 4 convolution
1118 code, so the actual data transmission rate is 1/2 of the
1119 modulation bit rate specified here.
1120 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37467184"></a>7.5. APRS Interval</h3></div></div></div><p>
1121 This selects how often APRS packets are transmitted. Set
1122 this to zero to disable APRS without also disabling the
1123 regular telemetry and RDF transmissions. As APRS takes a
1124 full second to transmit a single position report, we
1125 recommend sending packets no more than once every 5 seconds.
1126 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37468656"></a>7.6. APRS SSID</h3></div></div></div><p>
1127 This selects the SSID reported in APRS packets. By default,
1128 it is set to the last digit of the serial number, but you
1129 can change this to any value from 0 to 9.
1130 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37470000"></a>7.7. Apogee Delay</h3></div></div></div><p>
1131 Apogee delay is the number of seconds after the altimeter detects flight
1132 apogee that the drogue charge should be fired. In most cases, this
1133 should be left at the default of 0. However, if you are flying
1134 redundant electronics such as for an L3 certification, you may wish
1135 to set one of your altimeters to a positive delay so that both
1136 primary and backup pyrotechnic charges do not fire simultaneously.
1138 The Altus Metrum apogee detection algorithm fires exactly at
1139 apogee. If you are also flying an altimeter like the
1140 PerfectFlite MAWD, which only supports selecting 0 or 1
1141 seconds of apogee delay, you may wish to set the MAWD to 0
1142 seconds delay and set the TeleMetrum to fire your backup 2
1143 or 3 seconds later to avoid any chance of both charges
1144 firing simultaneously. We've flown several air-frames this
1145 way quite happily, including Keith's successful L3 cert.
1146 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37472592"></a>7.8. Apogee Lockout</h3></div></div></div><p>
1147 Apogee lockout is the number of seconds after boost where
1148 the flight computer will not fire the apogee charge, even if
1149 the rocket appears to be at apogee. This is often called
1150 'Mach Delay', as it is intended to prevent a flight computer
1151 from unintentionally firing apogee charges due to the pressure
1152 spike that occurrs across a mach transition. Altus Metrum
1153 flight computers include a Kalman filter which is not fooled
1154 by this sharp pressure increase, and so this setting should
1155 be left at the default value of zero to disable it.
1156 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37474320"></a>7.9. Main Deployment Altitude</h3></div></div></div><p>
1157 By default, the altimeter will fire the main deployment charge at an
1158 elevation of 250 meters (about 820 feet) above ground. We think this
1159 is a good elevation for most air-frames, but feel free to change this
1160 to suit. In particular, if you are flying two altimeters, you may
1162 deployment elevation for the backup altimeter to be something lower
1163 than the primary so that both pyrotechnic charges don't fire
1165 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37476016"></a>7.10. Maximum Flight Log</h3></div></div></div><p>
1166 Changing this value will set the maximum amount of flight
1167 log storage that an individual flight will use. The
1168 available storage is divided into as many flights of the
1169 specified size as can fit in the available space. You can
1170 download and erase individual flight logs. If you fill up
1171 the available storage, future flights will not get logged
1172 until you erase some of the stored ones.
1174 Even though our flight computers (except TeleMini v1.0) can store
1175 multiple flights, we strongly recommend downloading and saving
1176 flight data after each flight.
1177 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37478160"></a>7.11. Ignite Mode</h3></div></div></div><p>
1178 Instead of firing one charge at apogee and another charge at
1179 a fixed height above the ground, you can configure the
1180 altimeter to fire both at apogee or both during
1181 descent. This was added to support an airframe Bdale designed that
1182 had two altimeters, one in the fin can and one in the nose.
1184 Providing the ability to use both igniters for apogee or
1185 main allows some level of redundancy without needing two
1186 flight computers. In Redundant Apogee or Redundant Main
1187 mode, the two charges will be fired two seconds apart.
1188 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37480272"></a>7.12. Pad Orientation</h3></div></div></div><p>
1189 TeleMetrum, TeleMega and EasyMega measure acceleration along the axis
1190 of the board. Which way the board is oriented affects the
1191 sign of the acceleration value. Instead of trying to guess
1192 which way the board is mounted in the air frame, the
1193 altimeter must be explicitly configured for either Antenna
1194 Up or Antenna Down. The default, Antenna Up, expects the end
1195 of the board connected to the 70cm antenna to be nearest the
1196 nose of the rocket, with the end containing the screw
1197 terminals nearest the tail.
1198 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37481968"></a>7.13. Configurable Pyro Channels</h3></div></div></div><p>
1199 In addition to the usual Apogee and Main pyro channels,
1200 TeleMega and EasyMega have four additional channels that can be configured
1201 to activate when various flight conditions are
1202 satisfied. You can select as many conditions as necessary;
1203 all of them must be met in order to activate the
1204 channel. The conditions available are:
1205 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
1206 Acceleration away from the ground. Select a value, and
1207 then choose whether acceleration should be above or
1208 below that value. Acceleration is positive upwards, so
1209 accelerating towards the ground would produce negative
1210 numbers. Acceleration during descent is noisy and
1211 inaccurate, so be careful when using it during these
1212 phases of the flight.
1213 </p></li><li class="listitem"><p>
1214 Vertical speed. Select a value, and then choose whether
1215 vertical speed should be above or below that
1216 value. Speed is positive upwards, so moving towards the
1217 ground would produce negative numbers. Speed during
1218 descent is a bit noisy and so be careful when using it
1219 during these phases of the flight.
1220 </p></li><li class="listitem"><p>
1221 Height. Select a value, and then choose whether the
1222 height above the launch pad should be above or below
1224 </p></li><li class="listitem"><p>
1225 Orientation. TeleMega and EasyMega contain a 3-axis gyroscope and
1226 accelerometer which is used to measure the current
1227 angle. Note that this angle is not the change in angle
1228 from the launch pad, but rather absolute relative to
1229 gravity; the 3-axis accelerometer is used to compute the
1230 angle of the rocket on the launch pad and initialize the
1231 system. Because this value is computed by integrating
1232 rate gyros, it gets progressively less accurate as the
1233 flight goes on. It should have an accumulated error of
1234 less than 0.2°/second (after 10 seconds of flight, the
1235 error should be less than 2°).
1237 The usual use of the orientation configuration is to
1238 ensure that the rocket is traveling mostly upwards when
1239 deciding whether to ignite air starts or additional
1240 stages. For that, choose a reasonable maximum angle
1241 (like 20°) and set the motor igniter to require an angle
1242 of less than that value.
1243 </p></li><li class="listitem"><p>
1244 Flight Time. Time since boost was detected. Select a
1245 value and choose whether to activate the pyro channel
1246 before or after that amount of time.
1247 </p></li><li class="listitem"><p>
1248 Ascending. A simple test saying whether the rocket is
1249 going up or not. This is exactly equivalent to testing
1250 whether the speed is > 0.
1251 </p></li><li class="listitem"><p>
1252 Descending. A simple test saying whether the rocket is
1253 going down or not. This is exactly equivalent to testing
1254 whether the speed is < 0.
1255 </p></li><li class="listitem"><p>
1256 After Motor. The flight software counts each time the
1257 rocket starts accelerating (presumably due to a motor or
1258 motors igniting). Use this value to count ignitions for
1259 multi-staged or multi-airstart launches.
1260 </p></li><li class="listitem"><p>
1261 Delay. This value doesn't perform any checks, instead it
1262 inserts a delay between the time when the other
1263 parameters become true and when the pyro channel is
1265 </p></li><li class="listitem"><p>
1266 Flight State. The flight software tracks the flight
1267 through a sequence of states:
1268 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1269 Boost. The motor has lit and the rocket is
1270 accelerating upwards.
1271 </p></li><li class="listitem"><p>
1272 Fast. The motor has burned out and the rocket is
1273 decelerating, but it is going faster than 200m/s.
1274 </p></li><li class="listitem"><p>
1275 Coast. The rocket is still moving upwards and
1276 decelerating, but the speed is less than 200m/s.
1277 </p></li><li class="listitem"><p>
1278 Drogue. The rocket has reached apogee and is heading
1279 back down, but is above the configured Main
1281 </p></li><li class="listitem"><p>
1282 Main. The rocket is still descending, and is below
1284 </p></li><li class="listitem"><p>
1285 Landed. The rocket is no longer moving.
1286 </p></li></ol></div><p>
1288 You can select a state to limit when the pyro channel
1289 may activate; note that the check is based on when the
1290 rocket transitions <span class="emphasis"><em>into</em></span> the state, and so checking for
1291 “greater than Boost” means that the rocket is currently
1292 in boost or some later state.
1294 When a motor burns out, the rocket enters either Fast or
1295 Coast state (depending on how fast it is moving). If the
1296 computer detects upwards acceleration again, it will
1297 move back to Boost state.
1298 </p></li></ul></div></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp37504576"></a>Chapter 6. AltosUI</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp37508192">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37521120">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp37536752">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp37542208">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp37549072">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp37555504">1.5. Table</a></span></dt><dt><span class="section"><a href="#idp37559088">1.6. Site Map</a></span></dt><dt><span class="section"><a href="#idp37565408">1.7. Ignitor</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37569184">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp37573136">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp37575168">4. Graph Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37577552">4.1. Flight Graph</a></span></dt><dt><span class="section"><a href="#idp37582000">4.2. Configure Graph</a></span></dt><dt><span class="section"><a href="#idp37585664">4.3. Flight Statistics</a></span></dt><dt><span class="section"><a href="#idp37589184">4.4. Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37593040">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37594608">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp37596960">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37598448">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37610752">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp37612320">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp37613936">6.3. Apogee Lockoug</a></span></dt><dt><span class="section"><a href="#idp37616240">6.4. Frequency</a></span></dt><dt><span class="section"><a href="#idp37617744">6.5. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp37619392">6.6. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp37620688">6.7. Telemetry baud rate</a></span></dt><dt><span class="section"><a href="#idp37622256">6.8. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp37623824">6.9. APRS SSID</a></span></dt><dt><span class="section"><a href="#idp37625152">6.10. Callsign</a></span></dt><dt><span class="section"><a href="#idp37626464">6.11. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp37627904">6.12. Ignitor Firing Mode</a></span></dt><dt><span class="section"><a href="#idp37634816">6.13. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp37640048">6.14. Beeper Frequency</a></span></dt><dt><span class="section"><a href="#idp37641504">6.15. Configure Pyro Channels</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37647888">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37651392">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp37656416">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp37658416">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp37660656">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp37662160">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp37663440">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp37664944">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37666576">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37678080">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp37679648">8.2. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp37681168">8.3. Telemetry Rate</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37682640">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp37684304">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp37689936">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp37693808">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp37707856">13. Monitor Idle</a></span></dt></dl></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="414"><tr><td><img src="altosui.png" width="414"></td></tr></table></div></div><p>
1299 The AltosUI program provides a graphical user interface for
1300 interacting with the Altus Metrum product family. AltosUI can
1301 monitor telemetry data, configure devices and many other
1302 tasks. The primary interface window provides a selection of
1303 buttons, one for each major activity in the system. This chapter
1304 is split into sections, each of which documents one of the tasks
1305 provided from the top-level toolbar.
1306 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37508192"></a>1. Monitor Flight</h2></div><div><h3 class="subtitle">Receive, Record and Display Telemetry Data</h3></div></div></div><p>
1307 Selecting this item brings up a dialog box listing all of the
1308 connected TeleDongle devices. When you choose one of these,
1309 AltosUI will create a window to display telemetry data as
1310 received by the selected TeleDongle device.
1311 </p><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="279"><tr><td><img src="device-selection.png" width="279"></td></tr></table></div></div><p>
1312 All telemetry data received are automatically recorded in
1313 suitable log files. The name of the files includes the current
1314 date and rocket serial and flight numbers.
1316 The radio frequency being monitored by the TeleDongle device is
1317 displayed at the top of the window. You can configure the
1318 frequency by clicking on the frequency box and selecting the desired
1319 frequency. AltosUI remembers the last frequency selected for each
1320 TeleDongle and selects that automatically the next time you use
1323 Below the TeleDongle frequency selector, the window contains a few
1324 significant pieces of information about the altimeter providing
1325 the telemetry data stream:
1326 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>The configured call-sign</p></li><li class="listitem"><p>The device serial number</p></li><li class="listitem"><p>The flight number. Each altimeter remembers how many
1328 </p></li><li class="listitem"><p>
1329 The rocket flight state. Each flight passes through several
1330 states including Pad, Boost, Fast, Coast, Drogue, Main and
1332 </p></li><li class="listitem"><p>
1333 The Received Signal Strength Indicator value. This lets
1334 you know how strong a signal TeleDongle is receiving. At
1335 the default data rate, 38400 bps, in bench testing, the
1336 radio inside TeleDongle v0.2 operates down to about
1337 -106dBm, while the v3 radio works down to about -111dBm.
1338 Weaker signals, or an environment with radio noise may
1339 cause the data to not be received. The packet link uses
1340 error detection and correction techniques which prevent
1341 incorrect data from being reported.
1342 </p></li><li class="listitem"><p>
1343 The age of the displayed data, in seconds since the last
1344 successfully received telemetry packet. In normal operation
1345 this will stay in the low single digits. If the number starts
1346 counting up, then you are no longer receiving data over the radio
1347 link from the flight computer.
1348 </p></li></ul></div><p>
1349 Finally, the largest portion of the window contains a set of
1350 tabs, each of which contain some information about the rocket.
1351 They're arranged in 'flight order' so that as the flight
1352 progresses, the selected tab automatically switches to display
1353 data relevant to the current state of the flight. You can select
1354 other tabs at any time. The final 'table' tab displays all of
1355 the raw telemetry values in one place in a spreadsheet-like format.
1356 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37521120"></a>1.1. Launch Pad</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="launch-pad.png" width="495"></td></tr></table></div></div><p>
1357 The 'Launch Pad' tab shows information used to decide when the
1358 rocket is ready for flight. The first elements include red/green
1359 indicators, if any of these is red, you'll want to evaluate
1360 whether the rocket is ready to launch:
1361 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Battery Voltage</span></dt><dd><p>
1362 This indicates whether the Li-Po battery powering the
1363 flight computer has sufficient charge to last for
1364 the duration of the flight. A value of more than
1365 3.8V is required for a 'GO' status.
1366 </p></dd><dt><span class="term">Apogee Igniter Voltage</span></dt><dd><p>
1367 This indicates whether the apogee
1368 igniter has continuity. If the igniter has a low
1369 resistance, then the voltage measured here will be close
1370 to the Li-Po battery voltage. A value greater than 3.2V is
1371 required for a 'GO' status.
1372 </p></dd><dt><span class="term">Main Igniter Voltage</span></dt><dd><p>
1373 This indicates whether the main
1374 igniter has continuity. If the igniter has a low
1375 resistance, then the voltage measured here will be close
1376 to the Li-Po battery voltage. A value greater than 3.2V is
1377 required for a 'GO' status.
1378 </p></dd><dt><span class="term">On-board Data Logging</span></dt><dd><p>
1379 This indicates whether there is
1380 space remaining on-board to store flight data for the
1381 upcoming flight. If you've downloaded data, but failed
1382 to erase flights, there may not be any space
1383 left. Most of our flight computers can store multiple
1384 flights, depending on the configured maximum flight log
1385 size. TeleMini v1.0 stores only a single flight, so it
1387 downloaded and erased after each flight to capture
1388 data. This only affects on-board flight logging; the
1389 altimeter will still transmit telemetry and fire
1390 ejection charges at the proper times even if the flight
1391 data storage is full.
1392 </p></dd><dt><span class="term">GPS Locked</span></dt><dd><p>
1393 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
1394 currently able to compute position information. GPS requires
1395 at least 4 satellites to compute an accurate position.
1396 </p></dd><dt><span class="term">GPS Ready</span></dt><dd><p>
1397 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
1398 10 consecutive positions without losing lock. This ensures
1399 that the GPS receiver has reliable reception from the
1401 </p></dd></dl></div><p>
1403 The Launchpad tab also shows the computed launch pad position
1404 and altitude, averaging many reported positions to improve the
1405 accuracy of the fix.
1406 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37536752"></a>1.2. Ascent</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="ascent.png" width="495"></td></tr></table></div></div><p>
1407 This tab is shown during Boost, Fast and Coast
1408 phases. The information displayed here helps monitor the
1409 rocket as it heads towards apogee.
1411 The height, speed, acceleration and tilt are shown along
1412 with the maximum values for each of them. This allows you to
1413 quickly answer the most commonly asked questions you'll hear
1416 The current latitude and longitude reported by the GPS are
1417 also shown. Note that under high acceleration, these values
1418 may not get updated as the GPS receiver loses position
1419 fix. Once the rocket starts coasting, the receiver should
1420 start reporting position again.
1422 Finally, the current igniter voltages are reported as in the
1423 Launch Pad tab. This can help diagnose deployment failures
1424 caused by wiring which comes loose under high acceleration.
1425 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37542208"></a>1.3. Descent</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="descent.png" width="495"></td></tr></table></div></div><p>
1426 Once the rocket has reached apogee and (we hope) activated the
1427 apogee charge, attention switches to tracking the rocket on
1428 the way back to the ground, and for dual-deploy flights,
1429 waiting for the main charge to fire.
1431 To monitor whether the apogee charge operated correctly, the
1432 current descent rate is reported along with the current
1433 height. Good descent rates vary based on the choice of recovery
1434 components, but generally range from 15-30m/s on drogue and should
1435 be below 10m/s when under the main parachute in a dual-deploy flight.
1437 With GPS-equipped flight computers, you can locate the rocket in the
1438 sky using the elevation and bearing information to figure
1439 out where to look. Elevation is in degrees above the
1440 horizon. Bearing is reported in degrees relative to true
1441 north. Range can help figure out how big the rocket will
1442 appear. Ground Distance shows how far it is to a point
1443 directly under the rocket and can help figure out where the
1444 rocket is likely to land. Note that all of these values are
1445 relative to the pad location. If the elevation is near 90°,
1446 the rocket is over the pad, not over you.
1448 Finally, the igniter voltages are reported in this tab as
1449 well, both to monitor the main charge as well as to see what
1450 the status of the apogee charge is. Note that some commercial
1451 e-matches are designed to retain continuity even after being
1452 fired, and will continue to show as green or return from red to
1454 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37549072"></a>1.4. Landed</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="landed.png" width="495"></td></tr></table></div></div><p>
1455 Once the rocket is on the ground, attention switches to
1456 recovery. While the radio signal is often lost once the
1457 rocket is on the ground, the last reported GPS position is
1458 generally within a short distance of the actual landing location.
1460 The last reported GPS position is reported both by
1461 latitude and longitude as well as a bearing and distance from
1462 the launch pad. The distance should give you a good idea of
1463 whether to walk or hitch a ride. Take the reported
1464 latitude and longitude and enter them into your hand-held GPS
1465 unit and have that compute a track to the landing location.
1467 Our flight computers will continue to transmit RDF
1468 tones after landing, allowing you to locate the rocket by
1469 following the radio signal if necessary. You may need to get
1470 away from the clutter of the flight line, or even get up on
1471 a hill (or your neighbor's RV roof) to receive the RDF signal.
1473 The maximum height, speed and acceleration reported
1474 during the flight are displayed for your admiring observers.
1475 The accuracy of these immediate values depends on the quality
1476 of your radio link and how many packets were received.
1477 Recovering the on-board data after flight may yield
1478 more precise results.
1480 To get more detailed information about the flight, you can
1481 click on the 'Graph Flight' button which will bring up a
1482 graph window for the current flight.
1483 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37555504"></a>1.5. Table</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="table.png" width="495"></td></tr></table></div></div><p>
1484 The table view shows all of the data available from the
1485 flight computer. Probably the most useful data on
1486 this tab is the detailed GPS information, which includes
1487 horizontal dilution of precision information, and
1488 information about the signal being received from the satellites.
1489 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37559088"></a>1.6. Site Map</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="site-map.png" width="495"></td></tr></table></div></div><p>
1490 When the TeleMetrum has a GPS fix, the Site Map tab will map
1491 the rocket's position to make it easier for you to locate the
1492 rocket, both while it is in the air, and when it has landed. The
1493 rocket's state is indicated by color: white for pad, red for
1494 boost, pink for fast, yellow for coast, light blue for drogue,
1495 dark blue for main, and black for landed.
1497 The map's default scale is approximately 3m (10ft) per pixel. The map
1498 can be dragged using the left mouse button. The map will attempt
1499 to keep the rocket roughly centered while data is being received.
1501 You can adjust the style of map and the zoom level with
1502 buttons on the right side of the map window. You can draw a
1503 line on the map by moving the mouse over the map with a
1504 button other than the left one pressed, or by pressing the
1505 left button while also holding down the shift key. The
1506 length of the line in real-world units will be shown at the
1509 Images are fetched automatically via the Google Maps Static API,
1510 and cached on disk for reuse. If map images cannot be downloaded,
1511 the rocket's path will be traced on a dark gray background
1514 You can pre-load images for your favorite launch sites
1515 before you leave home; check out the 'Preload Maps' section below.
1516 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37565408"></a>1.7. Ignitor</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="ignitor.png" width="495"></td></tr></table></div></div><p>
1517 TeleMega includes four additional programmable pyro
1518 channels. The Ignitor tab shows whether each of them has
1519 continuity. If an ignitor has a low resistance, then the
1520 voltage measured here will be close to the pyro battery
1521 voltage. A value greater than 3.2V is required for a 'GO'
1523 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37569184"></a>2. Save Flight Data</h2></div></div></div><p>
1524 The altimeter records flight data to its internal flash memory.
1525 TeleMetrum data is recorded at a much higher rate than the telemetry
1526 system can handle, and is not subject to radio drop-outs. As
1527 such, it provides a more complete and precise record of the
1528 flight. The 'Save Flight Data' button allows you to read the
1529 flash memory and write it to disk.
1531 Clicking on the 'Save Flight Data' button brings up a list of
1532 connected flight computers and TeleDongle devices. If you select a
1533 flight computer, the flight data will be downloaded from that
1534 device directly. If you select a TeleDongle device, flight data
1535 will be downloaded from a flight computer over radio link via the
1536 specified TeleDongle. See the chapter on Controlling An Altimeter
1537 Over The Radio Link for more information.
1539 After the device has been selected, a dialog showing the
1540 flight data saved in the device will be shown allowing you to
1541 select which flights to download and which to delete. With
1542 version 0.9 or newer firmware, you must erase flights in order
1543 for the space they consume to be reused by another
1544 flight. This prevents accidentally losing flight data
1545 if you neglect to download data before flying again. Note that
1546 if there is no more space available in the device, then no
1547 data will be recorded during the next flight.
1549 The file name for each flight log is computed automatically
1550 from the recorded flight date, altimeter serial number and
1551 flight number information.
1552 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37573136"></a>3. Replay Flight</h2></div></div></div><p>
1553 Select this button and you are prompted to select a flight
1554 record file, either a .telem file recording telemetry data or a
1555 .eeprom file containing flight data saved from the altimeter
1558 Once a flight record is selected, the flight monitor interface
1559 is displayed and the flight is re-enacted in real time. Check
1560 the Monitor Flight chapter above to learn how this window operates.
1561 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37575168"></a>4. Graph Data</h2></div></div></div><p>
1562 Select this button and you are prompted to select a flight
1563 record file, either a .telem file recording telemetry data or a
1564 .eeprom file containing flight data saved from
1567 Note that telemetry files will generally produce poor graphs
1568 due to the lower sampling rate and missed telemetry packets.
1569 Use saved flight data in .eeprom files for graphing where possible.
1571 Once a flight record is selected, a window with multiple tabs is
1573 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37577552"></a>4.1. Flight Graph</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="540"><tr><td><img src="graph.png" width="540"></td></tr></table></div></div><p>
1574 By default, the graph contains acceleration (blue),
1575 velocity (green) and altitude (red).
1577 The graph can be zoomed into a particular area by clicking and
1578 dragging down and to the right. Once zoomed, the graph can be
1579 reset by clicking and dragging up and to the left. Holding down
1580 control and clicking and dragging allows the graph to be panned.
1581 The right mouse button causes a pop-up menu to be displayed, giving
1582 you the option save or print the plot.
1583 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37582000"></a>4.2. Configure Graph</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="540"><tr><td><img src="graph-configure.png" width="540"></td></tr></table></div></div><p>
1584 This selects which graph elements to show, and, at the
1585 very bottom, lets you switch between metric and
1587 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37585664"></a>4.3. Flight Statistics</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="540"><tr><td><img src="graph-stats.png" width="540"></td></tr></table></div></div><p>
1588 Shows overall data computed from the flight.
1589 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37589184"></a>4.4. Map</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="540"><tr><td><img src="graph-map.png" width="540"></td></tr></table></div></div><p>
1590 Shows a satellite image of the flight area overlaid
1591 with the path of the flight. The red concentric
1592 circles mark the launch pad, the black concentric
1593 circles mark the landing location.
1594 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37593040"></a>5. Export Data</h2></div></div></div><p>
1595 This tool takes the raw data files and makes them available for
1596 external analysis. When you select this button, you are prompted to
1597 select a flight data file, which can be either a .eeprom or .telem.
1598 The .eeprom files contain higher resolution and more continuous data,
1599 while .telem files contain receiver signal strength information.
1600 Next, a second dialog appears which is used to select
1601 where to write the resulting file. It has a selector to choose
1602 between CSV and KML file formats.
1603 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37594608"></a>5.1. Comma Separated Value Format</h3></div></div></div><p>
1604 This is a text file containing the data in a form suitable for
1605 import into a spreadsheet or other external data analysis
1606 tool. The first few lines of the file contain the version and
1607 configuration information from the altimeter, then
1608 there is a single header line which labels all of the
1609 fields. All of these lines start with a '#' character which
1610 many tools can be configured to skip over.
1612 The remaining lines of the file contain the data, with each
1613 field separated by a comma and at least one space. All of
1614 the sensor values are converted to standard units, with the
1615 barometric data reported in both pressure, altitude and
1616 height above pad units.
1617 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37596960"></a>5.2. Keyhole Markup Language (for Google Earth)</h3></div></div></div><p>
1618 This is the format used by Google Earth to provide an overlay
1619 within that application. With this, you can use Google Earth to
1620 see the whole flight path in 3D.
1621 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37598448"></a>6. Configure Altimeter</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="324"><tr><td><img src="configure-altimeter.png" width="324"></td></tr></table></div></div><p>
1622 Select this button and then select either an altimeter or
1623 TeleDongle Device from the list provided. Selecting a TeleDongle
1624 device will use the radio link to configure a remote altimeter.
1626 The first few lines of the dialog provide information about the
1627 connected device, including the product name,
1628 software version and hardware serial number. Below that are the
1629 individual configuration entries.
1631 At the bottom of the dialog, there are four buttons:
1632 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Save</span></dt><dd><p>
1633 This writes any changes to the
1634 configuration parameter block in flash memory. If you don't
1635 press this button, any changes you make will be lost.
1636 </p></dd><dt><span class="term">Reset</span></dt><dd><p>
1637 This resets the dialog to the most recently saved values,
1638 erasing any changes you have made.
1639 </p></dd><dt><span class="term">Reboot</span></dt><dd><p>
1640 This reboots the device. Use this to
1641 switch from idle to pad mode by rebooting once the rocket is
1642 oriented for flight, or to confirm changes you think you saved
1644 </p></dd><dt><span class="term">Close</span></dt><dd><p>
1645 This closes the dialog. Any unsaved changes will be
1647 </p></dd></dl></div><p>
1648 The rest of the dialog contains the parameters to be configured.
1649 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37610752"></a>6.1. Main Deploy Altitude</h3></div></div></div><p>
1650 This sets the altitude (above the recorded pad altitude) at
1651 which the 'main' igniter will fire. The drop-down menu shows
1652 some common values, but you can edit the text directly and
1653 choose whatever you like. If the apogee charge fires below
1654 this altitude, then the main charge will fire two seconds
1655 after the apogee charge fires.
1656 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37612320"></a>6.2. Apogee Delay</h3></div></div></div><p>
1657 When flying redundant electronics, it's often important to
1658 ensure that multiple apogee charges don't fire at precisely
1659 the same time, as that can over pressurize the apogee deployment
1660 bay and cause a structural failure of the air-frame. The Apogee
1661 Delay parameter tells the flight computer to fire the apogee
1662 charge a certain number of seconds after apogee has been
1664 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37613936"></a>6.3. Apogee Lockoug</h3></div></div></div><p>
1665 Apogee lockout is the number of seconds after boost where
1666 the flight computer will not fire the apogee charge, even if
1667 the rocket appears to be at apogee. This is often called
1668 'Mach Delay', as it is intended to prevent a flight computer
1669 from unintentionally firing apogee charges due to the pressure
1670 spike that occurrs across a mach transition. Altus Metrum
1671 flight computers include a Kalman filter which is not fooled
1672 by this sharp pressure increase, and so this setting should
1673 be left at the default value of zero to disable it.
1674 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37616240"></a>6.4. Frequency</h3></div></div></div><p>
1675 This configures which of the frequencies to use for both
1676 telemetry and packet command mode. Note that if you set this
1677 value via packet command mode, the TeleDongle frequency will
1678 also be automatically reconfigured to match so that
1679 communication will continue afterwards.
1680 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37617744"></a>6.5. RF Calibration</h3></div></div></div><p>
1681 The radios in every Altus Metrum device are calibrated at the
1682 factory to ensure that they transmit and receive on the
1683 specified frequency. If you need to you can adjust the calibration
1684 by changing this value. Do not do this without understanding what
1685 the value means, read the appendix on calibration and/or the source
1686 code for more information. To change a TeleDongle's calibration,
1687 you must reprogram the unit completely.
1688 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37619392"></a>6.6. Telemetry/RDF/APRS Enable</h3></div></div></div><p>
1689 Enables the radio for transmission during flight. When
1690 disabled, the radio will not transmit anything during flight
1692 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37620688"></a>6.7. Telemetry baud rate</h3></div></div></div><p>
1693 This sets the modulation bit rate for data transmission for
1694 both telemetry and packet link mode. Lower bit
1695 rates will increase range while reducing the amount of data
1696 that can be sent and increasing battery consumption. All
1697 telemetry is done using a rate 1/2 constraint 4 convolution
1698 code, so the actual data transmission rate is 1/2 of the
1699 modulation bit rate specified here.
1700 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37622256"></a>6.8. APRS Interval</h3></div></div></div><p>
1701 How often to transmit GPS information via APRS (in
1702 seconds). When set to zero, APRS transmission is
1703 disabled. This option is available on TeleMetrum v2 and
1704 TeleMega boards. TeleMetrum v1 boards cannot transmit APRS
1705 packets. Note that a single APRS packet takes nearly a full
1706 second to transmit, so enabling this option will prevent
1707 sending any other telemetry during that time.
1708 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37623824"></a>6.9. APRS SSID</h3></div></div></div><p>
1709 Which SSID to report in APRS packets. By default, this is
1710 set to the last digit of the serial number, but can be
1711 configured to any value from 0 to 9.
1712 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37625152"></a>6.10. Callsign</h3></div></div></div><p>
1713 This sets the call sign included in each telemetry packet. Set this
1714 as needed to conform to your local radio regulations.
1715 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37626464"></a>6.11. Maximum Flight Log Size</h3></div></div></div><p>
1716 This sets the space (in kilobytes) allocated for each flight
1717 log. The available space will be divided into chunks of this
1718 size. A smaller value will allow more flights to be stored,
1719 a larger value will record data from longer flights.
1720 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37627904"></a>6.12. Ignitor Firing Mode</h3></div></div></div><p>
1721 This configuration parameter allows the two standard ignitor
1722 channels (Apogee and Main) to be used in different
1724 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Dual Deploy</span></dt><dd><p>
1725 This is the usual mode of operation; the
1726 'apogee' channel is fired at apogee and the 'main'
1727 channel at the height above ground specified by the
1728 'Main Deploy Altitude' during descent.
1729 </p></dd><dt><span class="term">Redundant Apogee</span></dt><dd><p>
1730 This fires both channels at
1731 apogee, the 'apogee' channel first followed after a two second
1732 delay by the 'main' channel.
1733 </p></dd><dt><span class="term">Redundant Main</span></dt><dd><p>
1734 This fires both channels at the
1735 height above ground specified by the Main Deploy
1736 Altitude setting during descent. The 'apogee'
1737 channel is fired first, followed after a two second
1738 delay by the 'main' channel.
1739 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37634816"></a>6.13. Pad Orientation</h3></div></div></div><p>
1740 Because they include accelerometers, TeleMetrum,
1741 TeleMega and EasyMega are sensitive to the orientation of the board. By
1742 default, they expect the antenna end to point forward. This
1743 parameter allows that default to be changed, permitting the
1744 board to be mounted with the antenna pointing aft instead.
1745 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Antenna Up</span></dt><dd><p>
1746 In this mode, the antenna end of the
1747 flight computer must point forward, in line with the
1748 expected flight path.
1749 </p></dd><dt><span class="term">Antenna Down</span></dt><dd><p>
1750 In this mode, the antenna end of the
1751 flight computer must point aft, in line with the
1752 expected flight path.
1753 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37640048"></a>6.14. Beeper Frequency</h3></div></div></div><p>
1754 The beeper on all Altus Metrum flight computers works best
1755 at 4000Hz, however if you have more than one flight computer
1756 in a single airframe, having all of them sound at the same
1757 frequency can be confusing. This parameter lets you adjust
1758 the base beeper frequency value.
1759 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37641504"></a>6.15. Configure Pyro Channels</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="540"><tr><td><img src="configure-pyro.png" width="540"></td></tr></table></div></div><p>
1760 This opens a separate window to configure the additional
1761 pyro channels available on TeleMega and EasyMega. One column is
1762 presented for each channel. Each row represents a single
1763 parameter, if enabled the parameter must meet the specified
1764 test for the pyro channel to be fired. See the Pyro Channels
1765 section in the System Operation chapter above for a
1766 description of these parameters.
1768 Select conditions and set the related value; the pyro
1769 channel will be activated when <span class="emphasis"><em>all</em></span> of the
1770 conditions are met. Each pyro channel has a separate set of
1771 configuration values, so you can use different values for
1772 the same condition with different channels.
1774 At the bottom of the window, the 'Pyro Firing Time'
1775 configuration sets the length of time (in seconds) which
1776 each of these pyro channels will fire for.
1778 Once you have selected the appropriate configuration for all
1779 of the necessary pyro channels, you can save the pyro
1780 configuration along with the rest of the flight computer
1781 configuration by pressing the 'Save' button in the main
1782 Configure Flight Computer window.
1783 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37647888"></a>7. Configure AltosUI</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="216"><tr><td><img src="configure-altosui.png" width="216"></td></tr></table></div></div><p>
1784 This button presents a dialog so that you can configure the AltosUI global settings.
1785 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37651392"></a>7.1. Voice Settings</h3></div></div></div><p>
1786 AltosUI provides voice announcements during flight so that you
1787 can keep your eyes on the sky and still get information about
1788 the current flight status. However, sometimes you don't want
1790 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Enable</span></dt><dd><p>Turns all voice announcements on and off</p></dd><dt><span class="term">Test Voice</span></dt><dd><p>
1791 Plays a short message allowing you to verify
1792 that the audio system is working and the volume settings
1794 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37656416"></a>7.2. Log Directory</h3></div></div></div><p>
1795 AltosUI logs all telemetry data and saves all TeleMetrum flash
1796 data to this directory. This directory is also used as the
1797 staring point when selecting data files for display or export.
1799 Click on the directory name to bring up a directory choosing
1800 dialog, select a new directory and click 'Select Directory' to
1801 change where AltosUI reads and writes data files.
1802 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37658416"></a>7.3. Callsign</h3></div></div></div><p>
1803 This value is transmitted in each command packet sent from
1804 TeleDongle and received from an altimeter. It is not used in
1805 telemetry mode, as the callsign configured in the altimeter board
1806 is included in all telemetry packets. Configure this
1807 with the AltosUI operators call sign as needed to comply with
1808 your local radio regulations.
1810 Note that to successfully command a flight computer over the radio
1811 (to configure the altimeter, monitor idle, or fire pyro charges),
1812 the callsign configured here must exactly match the callsign
1813 configured in the flight computer. This matching is case
1815 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37660656"></a>7.4. Imperial Units</h3></div></div></div><p>
1816 This switches between metric units (meters) and imperial
1817 units (feet and miles). This affects the display of values
1818 use during flight monitoring, configuration, data graphing
1819 and all of the voice announcements. It does not change the
1820 units used when exporting to CSV files, those are always
1821 produced in metric units.
1822 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37662160"></a>7.5. Font Size</h3></div></div></div><p>
1823 Selects the set of fonts used in the flight monitor
1824 window. Choose between the small, medium and large sets.
1825 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37663440"></a>7.6. Serial Debug</h3></div></div></div><p>
1826 This causes all communication with a connected device to be
1827 dumped to the console from which AltosUI was started. If
1828 you've started it from an icon or menu entry, the output
1829 will simply be discarded. This mode can be useful to debug
1830 various serial communication issues.
1831 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37664944"></a>7.7. Manage Frequencies</h3></div></div></div><p>
1832 This brings up a dialog where you can configure the set of
1833 frequencies shown in the various frequency menus. You can
1834 add as many as you like, or even reconfigure the default
1835 set. Changing this list does not affect the frequency
1836 settings of any devices, it only changes the set of
1837 frequencies shown in the menus.
1838 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37666576"></a>8. Configure Groundstation</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="279"><tr><td><img src="configure-groundstation.png" width="279"></td></tr></table></div></div><p>
1839 Select this button and then select a TeleDongle or TeleBT Device from the list provided.
1841 The first few lines of the dialog provide information about the
1842 connected device, including the product name,
1843 software version and hardware serial number. Below that are the
1844 individual configuration entries.
1846 Note that TeleDongle and TeleBT don't save any configuration
1847 data, the settings here are recorded on the local machine in
1848 the Java preferences database. Moving the device to
1849 another machine, or using a different user account on the same
1850 machine will cause settings made here to have no effect.
1852 At the bottom of the dialog, there are three buttons:
1853 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Save</span></dt><dd><p>
1854 This writes any changes to the
1855 local Java preferences file. If you don't
1856 press this button, any changes you make will be lost.
1857 </p></dd><dt><span class="term">Reset</span></dt><dd><p>
1858 This resets the dialog to the most recently saved values,
1859 erasing any changes you have made.
1860 </p></dd><dt><span class="term">Close</span></dt><dd><p>
1861 This closes the dialog. Any unsaved changes will be
1863 </p></dd></dl></div><p>
1864 The rest of the dialog contains the parameters to be configured.
1865 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37678080"></a>8.1. Frequency</h3></div></div></div><p>
1866 This configures the frequency to use for both telemetry and
1867 packet command mode. Set this before starting any operation
1868 involving packet command mode so that it will use the right
1869 frequency. Telemetry monitoring mode also provides a menu to
1870 change the frequency, and that menu also sets the same Java
1871 preference value used here.
1872 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37679648"></a>8.2. RF Calibration</h3></div></div></div><p>
1873 The radios in every Altus Metrum device are calibrated at the
1874 factory to ensure that they transmit and receive on the
1875 specified frequency. To change a TeleDongle or TeleBT's calibration,
1876 you must reprogram the unit completely, so this entry simply
1877 shows the current value and doesn't allow any changes.
1878 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37681168"></a>8.3. Telemetry Rate</h3></div></div></div><p>
1879 This lets you match the telemetry and packet link rate from
1880 the transmitter. If they don't match, the device won't
1882 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37682640"></a>9. Flash Image</h2></div></div></div><p>
1883 This reprograms Altus Metrum devices with new
1884 firmware. TeleMetrum v1.x, TeleDongle v0.2, TeleMini and
1885 TeleBT are all reprogrammed by using another similar unit as a
1886 programming dongle (pair programming). TeleMega, EasyMega,
1887 TeleMetrum v2, EasyMini and TeleDongle v3 are all programmed
1888 directly over their USB ports (self programming). Please read
1889 the directions for flashing devices in the Updating Device
1890 Firmware chapter below.
1891 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37684304"></a>10. Fire Igniter</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="108"><tr><td><img src="fire-igniter.png" width="108"></td></tr></table></div></div><p>
1892 This activates the igniter circuits in the flight computer to help
1893 test recovery systems deployment. Because this command can operate
1894 over the Packet Command Link, you can prepare the rocket as
1895 for flight and then test the recovery system without needing
1896 to snake wires inside the air-frame.
1898 Selecting the 'Fire Igniter' button brings up the usual device
1899 selection dialog. Pick the desired device. This brings up another
1900 window which shows the current continuity test status for all
1901 of the pyro channels.
1903 Next, select the desired igniter to fire. This will enable the
1906 Select the 'Arm' button. This enables the 'Fire' button. The
1907 word 'Arm' is replaced by a countdown timer indicating that
1908 you have 10 seconds to press the 'Fire' button or the system
1909 will deactivate, at which point you start over again at
1910 selecting the desired igniter.
1911 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37689936"></a>11. Scan Channels</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="288"><tr><td><img src="scan-channels.png" width="288"></td></tr></table></div></div><p>
1912 This listens for telemetry packets on all of the configured
1913 frequencies, displaying information about each device it
1914 receives a packet from. You can select which of the baud rates
1915 and telemetry formats should be tried; by default, it only listens
1916 at 38400 baud with the standard telemetry format used in v1.0 and later
1918 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37693808"></a>12. Load Maps</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="468"><tr><td><img src="load-maps.png" width="468"></td></tr></table></div></div><p>
1919 Before heading out to a new launch site, you can use this to
1920 load satellite images in case you don't have internet
1921 connectivity at the site. This loads a fairly large area
1922 around the launch site, which should cover any flight you're likely to make.
1924 There's a drop-down menu of launch sites we know about; if
1925 your favorites aren't there, please let us know the lat/lon
1926 and name of the site. The contents of this list are actually
1927 downloaded from our server at run-time, so as new sites are sent
1928 in, they'll get automatically added to this list.
1929 If the launch site isn't in the list, you can manually enter the lat/lon values
1931 There are four different kinds of maps you can view; you can
1932 select which to download by selecting as many as you like from
1933 the available types:
1934 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Hybrid</span></dt><dd><p>
1935 A combination of satellite imagery and road data. This
1936 is the default view.
1937 </p></dd><dt><span class="term">Satellite</span></dt><dd><p>
1938 Just the satellite imagery without any annotation.
1939 </p></dd><dt><span class="term">Roadmap</span></dt><dd><p>
1940 Roads, political boundaries and a few geographic features.
1941 </p></dd><dt><span class="term">Terrain</span></dt><dd><p>
1942 Contour intervals and shading that show hills and
1944 </p></dd></dl></div><p>
1946 You can specify the range of zoom levels to download; smaller
1947 numbers show more area with less resolution. The default
1948 level, 0, shows about 3m/pixel. One zoom level change
1949 doubles or halves that number.
1951 The Tile Radius value sets how large an area around the center
1952 point to download. Each tile is 512x512 pixels, and the
1953 'radius' value specifies how many tiles away from the center
1954 will be downloaded. Specify a radius of 0 and you get only the
1955 center tile. A radius of 1 loads a 3x3 grid, centered on the
1958 Clicking the 'Load Map' button will fetch images from Google
1959 Maps; note that Google limits how many images you can fetch at
1960 once, so if you load more than one launch site, you may get
1961 some gray areas in the map which indicate that Google is tired
1962 of sending data to you. Try again later.
1963 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37707856"></a>13. Monitor Idle</h2></div></div></div><p>
1964 This brings up a dialog similar to the Monitor Flight UI,
1965 except it works with the altimeter in “idle” mode by sending
1966 query commands to discover the current state rather than
1967 listening for telemetry packets. Because this uses command
1968 mode, it needs to have the TeleDongle and flight computer
1969 callsigns match exactly. If you can receive telemetry, but
1970 cannot manage to run Monitor Idle, then it's very likely that
1971 your callsigns are different in some way.
1972 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp37709952"></a>Chapter 7. AltosDroid</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp37712336">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp37714272">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp37716272">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp37717728">4. AltosDroid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp37719040">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37732592">5. Downloading Flight Logs</a></span></dt></dl></div><p>
1973 AltosDroid provides the same flight monitoring capabilities as
1974 AltosUI, but runs on Android devices and is designed to connect
1975 to a TeleBT receiver over Bluetooth™. AltosDroid monitors
1976 telemetry data, logging it to internal storage in the Android
1977 device, and presents that data in a UI the same way the 'Monitor
1978 Flight' window does in AltosUI.
1980 This manual will explain how to configure AltosDroid, connect
1981 to TeleBT, operate the flight monitoring interface and describe
1982 what the displayed data means.
1983 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37712336"></a>1. Installing AltosDroid</h2></div></div></div><p>
1984 AltosDroid is available from the Google Play store. To install
1985 it on your Android device, open the Google Play Store
1986 application and search for “altosdroid”. Make sure you don't
1987 have a space between “altos” and “droid” or you probably won't
1988 find what you want. That should bring you to the right page
1989 from which you can download and install the application.
1990 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37714272"></a>2. Connecting to TeleBT</h2></div></div></div><p>
1991 Press the Android 'Menu' button or soft-key to see the
1992 configuration options available. Select the 'Connect a device'
1993 option and then the 'Scan for devices' entry at the bottom to
1994 look for your TeleBT device. Select your device, and when it
1995 asks for the code, enter '1234'.
1997 Subsequent connections will not require you to enter that
1998 code, and your 'paired' device will appear in the list without
2000 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37716272"></a>3. Configuring AltosDroid</h2></div></div></div><p>
2001 The only configuration option available for AltosDroid is
2002 which frequency to listen on. Press the Android 'Menu' button
2003 or soft-key and pick the 'Select radio frequency' entry. That
2004 brings up a menu of pre-set radio frequencies; pick the one
2005 which matches your altimeter.
2006 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37717728"></a>4. AltosDroid Flight Monitoring</h2></div></div></div><p>
2007 AltosDroid is designed to mimic the AltosUI flight monitoring
2008 display, providing separate tabs for each stage of your rocket
2009 flight along with a tab containing a map of the local area
2010 with icons marking the current location of the altimeter and
2012 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37719040"></a>4.1. Pad</h3></div></div></div><p>
2013 The 'Launch Pad' tab shows information used to decide when the
2014 rocket is ready for flight. The first elements include red/green
2015 indicators, if any of these is red, you'll want to evaluate
2016 whether the rocket is ready to launch:
2017 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Battery Voltage</span></dt><dd><p>
2018 This indicates whether the Li-Po battery
2019 powering the TeleMetrum has sufficient charge to last for
2020 the duration of the flight. A value of more than
2021 3.8V is required for a 'GO' status.
2022 </p></dd><dt><span class="term">Apogee Igniter Voltage</span></dt><dd><p>
2023 This indicates whether the apogee
2024 igniter has continuity. If the igniter has a low
2025 resistance, then the voltage measured here will be close
2026 to the Li-Po battery voltage. A value greater than 3.2V is
2027 required for a 'GO' status.
2028 </p></dd><dt><span class="term">Main Igniter Voltage</span></dt><dd><p>
2029 This indicates whether the main
2030 igniter has continuity. If the igniter has a low
2031 resistance, then the voltage measured here will be close
2032 to the Li-Po battery voltage. A value greater than 3.2V is
2033 required for a 'GO' status.
2034 </p></dd><dt><span class="term">On-board Data Logging</span></dt><dd><p>
2035 This indicates whether there is
2036 space remaining on-board to store flight data for the
2037 upcoming flight. If you've downloaded data, but failed
2038 to erase flights, there may not be any space
2039 left. TeleMetrum can store multiple flights, depending
2040 on the configured maximum flight log size. TeleMini
2041 stores only a single flight, so it will need to be
2042 downloaded and erased after each flight to capture
2043 data. This only affects on-board flight logging; the
2044 altimeter will still transmit telemetry and fire
2045 ejection charges at the proper times.
2046 </p></dd><dt><span class="term">GPS Locked</span></dt><dd><p>
2047 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
2048 currently able to compute position information. GPS requires
2049 at least 4 satellites to compute an accurate position.
2050 </p></dd><dt><span class="term">GPS Ready</span></dt><dd><p>
2051 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
2052 10 consecutive positions without losing lock. This ensures
2053 that the GPS receiver has reliable reception from the
2055 </p></dd></dl></div><p>
2057 The Launchpad tab also shows the computed launch pad position
2058 and altitude, averaging many reported positions to improve the
2059 accuracy of the fix.
2060 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37732592"></a>5. Downloading Flight Logs</h2></div></div></div><p>
2061 AltosDroid always saves every bit of telemetry data it
2062 receives. To download that to a computer for use with AltosUI,
2063 simply remove the SD card from your Android device, or connect
2064 your device to your computer's USB port and browse the files
2065 on that device. You will find '.telem' files in the TeleMetrum
2066 directory that will work with AltosUI directly.
2067 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp37734256"></a>Chapter 8. Using Altus Metrum Products</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp37734896">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp37736800">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp37739328">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp37753120">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp37756432">5. Future Plans</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37734896"></a>1. Being Legal</h2></div></div></div><p>
2068 First off, in the US, you need an <a class="ulink" href="http://www.altusmetrum.org/Radio/" target="_top">amateur radio license</a> or
2069 other authorization to legally operate the radio transmitters that are part
2071 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37736800"></a>2. In the Rocket</h2></div></div></div><p>
2072 In the rocket itself, you just need a flight computer and
2073 a single-cell, 3.7 volt nominal Li-Po rechargeable battery. An
2074 850mAh battery weighs less than a 9V alkaline battery, and will
2075 run a TeleMetrum, TeleMega or EasyMega for hours.
2076 A 110mAh battery weighs less than a triple A battery and is a good
2077 choice for use with TeleMini or EasyMini.
2079 By default, we ship TeleMini, TeleMetrum and TeleMega flight computers with a simple wire antenna.
2080 If your electronics bay or the air-frame it resides within is made
2081 of carbon fiber, which is opaque to RF signals, you may prefer to
2082 install an SMA connector so that you can run a coaxial cable to an
2083 antenna mounted elsewhere in the rocket. However, note that the
2084 GPS antenna is fixed on all current products, so you really want
2085 to install the flight computer in a bay made of RF-transparent
2086 materials if at all possible.
2087 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37739328"></a>3. On the Ground</h2></div></div></div><p>
2088 To receive the data stream from the rocket, you need an antenna and short
2089 feed-line connected to one of our <a class="ulink" href="http://www.altusmetrum.org/TeleDongle/" target="_top">TeleDongle</a> units. If possible, use an SMA to BNC
2090 adapter instead of feedline between the antenna feedpoint and
2091 TeleDongle, as this will give you the best performance. The
2092 TeleDongle in turn plugs directly into the USB port on a notebook
2093 computer. Because TeleDongle looks like a simple serial port, your computer
2094 does not require special device drivers... just plug it in.
2096 The GUI tool, AltosUI, is written in Java and runs across
2097 Linux, Mac OS and Windows. There's also a suite of C tools
2098 for Linux which can perform most of the same tasks.
2100 Alternatively, a TeleBT attached with an SMA to BNC adapter at the
2101 feed point of a hand-held yagi used in conjunction with an Android
2102 device running AltosDroid makes an outstanding ground station.
2104 After the flight, you can use the radio link to extract the more detailed data
2105 logged in either TeleMetrum or TeleMini devices, or you can use a mini USB cable to plug into the
2106 TeleMetrum board directly. Pulling out the data without having to open up
2107 the rocket is pretty cool! A USB cable is also how you charge the Li-Po
2108 battery, so you'll want one of those anyway... the same cable used by lots
2109 of digital cameras and other modern electronic stuff will work fine.
2111 If your rocket lands out of sight, you may enjoy having a hand-held
2112 GPS receiver, so that you can put in a way-point for the last
2113 reported rocket position before touch-down. This makes looking for
2114 your rocket a lot like Geo-Caching... just go to the way-point and
2115 look around starting from there. AltosDroid on an Android device
2116 with GPS receiver works great for this, too!
2118 You may also enjoy having a ham radio “HT” that covers the 70cm band... you
2119 can use that with your antenna to direction-find the rocket on the ground
2120 the same way you can use a Walston or Beeline tracker. This can be handy
2121 if the rocket is hiding in sage brush or a tree, or if the last GPS position
2122 doesn't get you close enough because the rocket dropped into a canyon, or
2123 the wind is blowing it across a dry lake bed, or something like that... Keith
2124 currently uses a Yaesu FT1D, Bdale has a Yaesu VX-7R, which
2125 is a nicer radio in most ways but doesn't support APRS.
2127 So, to recap, on the ground the hardware you'll need includes:
2128 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2129 an antenna and feed-line or adapter
2130 </p></li><li class="listitem"><p>
2132 </p></li><li class="listitem"><p>
2134 </p></li><li class="listitem"><p>
2135 optionally, a hand-held GPS receiver
2136 </p></li><li class="listitem"><p>
2137 optionally, an HT or receiver covering 435 MHz
2138 </p></li></ol></div><p>
2140 The best hand-held commercial directional antennas we've found for radio
2141 direction finding rockets are from
2142 <a class="ulink" href="http://www.arrowantennas.com/" target="_top">
2145 The 440-3 and 440-5 are both good choices for finding a
2146 TeleMetrum- or TeleMini- equipped rocket when used with a suitable
2147 70cm HT. TeleDongle and an SMA to BNC adapter fit perfectly
2148 between the driven element and reflector of Arrow antennas.
2149 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37753120"></a>4. Data Analysis</h2></div></div></div><p>
2150 Our software makes it easy to log the data from each flight, both the
2151 telemetry received during the flight itself, and the more
2152 complete data log recorded in the flash memory on the altimeter
2153 board. Once this data is on your computer, our post-flight tools make it
2154 easy to quickly get to the numbers everyone wants, like apogee altitude,
2155 max acceleration, and max velocity. You can also generate and view a
2156 standard set of plots showing the altitude, acceleration, and
2157 velocity of the rocket during flight. And you can even export a TeleMetrum data file
2158 usable with Google Maps and Google Earth for visualizing the flight path
2159 in two or three dimensions!
2161 Our ultimate goal is to emit a set of files for each flight that can be
2162 published as a web page per flight, or just viewed on your local disk with
2164 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37756432"></a>5. Future Plans</h2></div></div></div><p>
2165 We have designed and prototyped several “companion boards” that
2166 can attach to the companion connector on TeleMetrum,
2167 TeleMega and EasyMega
2168 flight computers to collect more data, provide more pyro channels,
2169 and so forth. We do not yet know if or when any of these boards
2170 will be produced in enough quantity to sell. If you have specific
2171 interests for data collection or control of events in your rockets
2172 beyond the capabilities of our existing productions, please let
2175 Because all of our work is open, both the hardware designs and the
2176 software, if you have some great idea for an addition to the current
2177 Altus Metrum family, feel free to dive in and help! Or let us know
2178 what you'd like to see that we aren't already working on, and maybe
2179 we'll get excited about it too...
2182 <a class="ulink" href="http://altusmetrum.org/" target="_top">web site</a> for more news
2183 and information as our family of products evolves!
2184 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp37760272"></a>Chapter 9. Altimeter Installation Recommendations</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp37761728">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp37766560">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp37772128">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp37776912">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp37784480">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp37787280">6. Ground Testing</a></span></dt></dl></div><p>
2185 Building high-power rockets that fly safely is hard enough. Mix
2186 in some sophisticated electronics and a bunch of radio energy
2187 and some creativity and/or compromise may be required. This chapter
2188 contains some suggestions about how to install Altus Metrum
2189 products into a rocket air-frame, including how to safely and
2190 reliably mix a variety of electronics into the same air-frame.
2191 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37761728"></a>1. Mounting the Altimeter</h2></div></div></div><p>
2192 The first consideration is to ensure that the altimeter is
2193 securely fastened to the air-frame. For most of our products, we
2194 prefer nylon standoffs and nylon screws; they're good to at least 50G
2195 and cannot cause any electrical issues on the board. Metal screws
2196 and standoffs are fine, too, just be careful to avoid electrical
2197 shorts! For TeleMini v1.0, we usually cut small pieces of 1/16 inch
2199 under the screw holes, and then take 2x56 nylon screws and
2200 screw them through the TeleMini mounting holes, through the
2201 balsa and into the underlying material.
2202 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2203 Make sure accelerometer-equipped products like TeleMetrum,
2204 TeleMega and EasyMega are aligned precisely along the axis of
2205 acceleration so that the accelerometer can accurately
2206 capture data during the flight.
2207 </p></li><li class="listitem"><p>
2208 Watch for any metal touching components on the
2209 board. Shorting out connections on the bottom of the board
2210 can cause the altimeter to fail during flight.
2211 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37766560"></a>2. Dealing with the Antenna</h2></div></div></div><p>
2212 The antenna supplied is just a piece of solid, insulated,
2213 wire. If it gets damaged or broken, it can be easily
2214 replaced. It should be kept straight and not cut; bending or
2215 cutting it will change the resonant frequency and/or
2216 impedance, making it a less efficient radiator and thus
2217 reducing the range of the telemetry signal.
2219 Keeping metal away from the antenna will provide better range
2220 and a more even radiation pattern. In most rockets, it's not
2221 entirely possible to isolate the antenna from metal
2222 components; there are often bolts, all-thread and wires from other
2223 electronics to contend with. Just be aware that the more stuff
2224 like this around the antenna, the lower the range.
2226 Make sure the antenna is not inside a tube made or covered
2227 with conducting material. Carbon fiber is the most common
2228 culprit here -- CF is a good conductor and will effectively
2229 shield the antenna, dramatically reducing signal strength and
2230 range. Metallic flake paint is another effective shielding
2231 material which should be avoided around any antennas.
2233 If the ebay is large enough, it can be convenient to simply
2234 mount the altimeter at one end and stretch the antenna out
2235 inside. Taping the antenna to the sled can keep it straight
2236 under acceleration. If there are metal rods, keep the
2237 antenna as far away as possible.
2239 For a shorter ebay, it's quite practical to have the antenna
2240 run through a bulkhead and into an adjacent bay. Drill a small
2241 hole in the bulkhead, pass the antenna wire through it and
2242 then seal it up with glue or clay. We've also used acrylic
2243 tubing to create a cavity for the antenna wire. This works a
2244 bit better in that the antenna is known to stay straight and
2245 not get folded by recovery components in the bay. Angle the
2246 tubing towards the side wall of the rocket and it ends up
2247 consuming very little space.
2249 If you need to place the UHF antenna at a distance from the
2250 altimeter, you can replace the antenna with an edge-mounted
2251 SMA connector, and then run 50Ω coax from the board to the
2252 antenna. Building a remote antenna is beyond the scope of this
2254 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37772128"></a>3. Preserving GPS Reception</h2></div></div></div><p>
2255 The GPS antenna and receiver used in TeleMetrum and TeleMega is
2256 highly sensitive and normally have no trouble tracking enough
2257 satellites to provide accurate position information for
2258 recovering the rocket. However, there are many ways the GPS signal
2259 can end up attenuated, negatively affecting GPS performance.
2260 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2261 Conductive tubing or coatings. Carbon fiber and metal
2262 tubing, or metallic paint will all dramatically attenuate the
2263 GPS signal. We've never heard of anyone successfully
2264 receiving GPS from inside these materials.
2265 </p></li><li class="listitem"><p>
2266 Metal components near the GPS patch antenna. These will
2267 de-tune the patch antenna, changing the resonant frequency
2268 away from the L1 carrier and reduce the effectiveness of the
2269 antenna. You can place as much stuff as you like beneath the
2270 antenna as that's covered with a ground plane. But, keep
2271 wires and metal out from above the patch antenna.
2272 </p></li></ol></div><p>
2273 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37776912"></a>4. Radio Frequency Interference</h2></div></div></div><p>
2274 Any altimeter will generate RFI; the digital circuits use
2275 high-frequency clocks that spray radio interference across a
2276 wide band. Altus Metrum altimeters generate intentional radio
2277 signals as well, increasing the amount of RF energy around the board.
2279 Rocketry altimeters also use precise sensors measuring air
2280 pressure and acceleration. Tiny changes in voltage can cause
2281 these sensor readings to vary by a huge amount. When the
2282 sensors start mis-reporting data, the altimeter can either
2283 fire the igniters at the wrong time, or not fire them at all.
2285 Voltages are induced when radio frequency energy is
2286 transmitted from one circuit to another. Here are things that
2287 influence the induced voltage and current:
2288 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2289 Keep wires from different circuits apart. Moving circuits
2290 further apart will reduce RFI.
2291 </p></li><li class="listitem"><p>
2292 Avoid parallel wires from different circuits. The longer two
2293 wires run parallel to one another, the larger the amount of
2294 transferred energy. Cross wires at right angles to reduce
2296 </p></li><li class="listitem"><p>
2297 Twist wires from the same circuits. Two wires the same
2298 distance from the transmitter will get the same amount of
2299 induced energy which will then cancel out. Any time you have
2300 a wire pair running together, twist the pair together to
2301 even out distances and reduce RFI. For altimeters, this
2302 includes battery leads, switch hookups and igniter
2304 </p></li><li class="listitem"><p>
2305 Avoid resonant lengths. Know what frequencies are present
2306 in the environment and avoid having wire lengths near a
2307 natural resonant length. Altus Metrum products transmit on the
2308 70cm amateur band, so you should avoid lengths that are a
2309 simple ratio of that length; essentially any multiple of ¼
2310 of the wavelength (17.5cm).
2311 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37784480"></a>5. The Barometric Sensor</h2></div></div></div><p>
2312 Altusmetrum altimeters measure altitude with a barometric
2313 sensor, essentially measuring the amount of air above the
2314 rocket to figure out how high it is. A large number of
2315 measurements are taken as the altimeter initializes itself to
2316 figure out the pad altitude. Subsequent measurements are then
2317 used to compute the height above the pad.
2319 To accurately measure atmospheric pressure, the ebay
2320 containing the altimeter must be vented outside the
2321 air-frame. The vent must be placed in a region of linear
2322 airflow, have smooth edges, and away from areas of increasing or
2323 decreasing pressure.
2325 All barometric sensors are quite sensitive to chemical damage from
2326 the products of APCP or BP combustion, so make sure the ebay is
2327 carefully sealed from any compartment which contains ejection
2329 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37787280"></a>6. Ground Testing</h2></div></div></div><p>
2330 The most important aspect of any installation is careful
2331 ground testing. Bringing an air-frame up to the LCO table which
2332 hasn't been ground tested can lead to delays or ejection
2333 charges firing on the pad, or, even worse, a recovery system
2336 Do a 'full systems' test that includes wiring up all igniters
2337 without any BP and turning on all of the electronics in flight
2338 mode. This will catch any mistakes in wiring and any residual
2339 RFI issues that might accidentally fire igniters at the wrong
2340 time. Let the air-frame sit for several minutes, checking for
2341 adequate telemetry signal strength and GPS lock. If any igniters
2342 fire unexpectedly, find and resolve the issue before loading any
2345 Ground test the ejection charges. Prepare the rocket for
2346 flight, loading ejection charges and igniters. Completely
2347 assemble the air-frame and then use the 'Fire Igniters'
2348 interface through a TeleDongle to command each charge to
2349 fire. Make sure the charge is sufficient to robustly separate
2350 the air-frame and deploy the recovery system.
2351 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp37790448"></a>Chapter 10. Updating Device Firmware</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp37794528">1.
2352 Updating TeleMega, TeleMetrum v2, EasyMega, EasyMini or
2353 TeleDongle v3 Firmware
2354 </a></span></dt><dd><dl><dt><span class="section"><a href="#idp37803664">1.1. Recovering From Self-Flashing Failure</a></span></dt></dl></dd><dt><span class="section"><a href="#idp37824016">2. Pair Programming</a></span></dt><dt><span class="section"><a href="#idp37825472">3. Updating TeleMetrum v1.x Firmware</a></span></dt><dt><span class="section"><a href="#idp37838736">4. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp37852352">5. Updating TeleDongle v0.2 Firmware</a></span></dt></dl></div><p>
2355 TeleMega, TeleMetrum v2, EasyMega, EasyMini and TeleDongle v3
2356 are all programmed directly over their USB connectors (self
2357 programming). TeleMetrum v1, TeleMini and TeleDongle v0.2 are
2358 all programmed by using another device as a programmer (pair
2359 programming). It's important to recognize which kind of devices
2360 you have before trying to reprogram them.
2362 You may wish to begin by ensuring you have current firmware images.
2363 These are distributed as part of the AltOS software bundle that
2364 also includes the AltosUI ground station program. Newer ground
2365 station versions typically work fine with older firmware versions,
2366 so you don't need to update your devices just to try out new
2367 software features. You can always download the most recent
2368 version from <a class="ulink" href="http://www.altusmetrum.org/AltOS/" target="_top">http://www.altusmetrum.org/AltOS/</a>.
2370 If you need to update the firmware on a TeleDongle v0.2, we recommend
2371 updating the altimeter first, before updating TeleDongle. However,
2372 note that TeleDongle rarely need to be updated. Any firmware version
2373 1.0.1 or later will work, version 1.2.1 may have improved receiver
2374 performance slightly.
2376 Self-programmable devices (TeleMega, TeleMetrum v2, EasyMega and EasyMini)
2377 are reprogrammed by connecting them to your computer over USB
2378 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37794528"></a>1.
2379 Updating TeleMega, TeleMetrum v2, EasyMega, EasyMini or
2380 TeleDongle v3 Firmware
2381 </h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2382 Attach a battery if necessary and power switch to the target
2383 device. Power up the device.
2384 </p></li><li class="listitem"><p>
2385 Using a Micro USB cable, connect the target device to your
2386 computer's USB socket.
2387 </p></li><li class="listitem"><p>
2388 Run AltosUI, and select 'Flash Image' from the File menu.
2389 </p></li><li class="listitem"><p>
2390 Select the target device in the Device Selection dialog.
2391 </p></li><li class="listitem"><p>
2392 Select the image you want to flash to the device, which
2393 should have a name in the form
2394 <product>-v<product-version>-<software-version>.ihx, such
2395 as TeleMega-v1.0-1.3.0.ihx.
2396 </p></li><li class="listitem"><p>
2397 Make sure the configuration parameters are reasonable
2398 looking. If the serial number and/or RF configuration
2399 values aren't right, you'll need to change them.
2400 </p></li><li class="listitem"><p>
2401 Hit the 'OK' button and the software should proceed to flash
2402 the device with new firmware, showing a progress bar.
2403 </p></li><li class="listitem"><p>
2404 Verify that the device is working by using the 'Configure
2405 Altimeter' or 'Configure Groundstation' item to check over
2407 </p></li></ol></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp37803664"></a>1.1. Recovering From Self-Flashing Failure</h3></div></div></div><p>
2408 If the firmware loading fails, it can leave the device
2409 unable to boot. Not to worry, you can force the device to
2410 start the boot loader instead, which will let you try to
2411 flash the device again.
2413 On each device, connecting two pins from one of the exposed
2414 connectors will force the boot loader to start, even if the
2415 regular operating system has been corrupted in some way.
2416 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">TeleMega</span></dt><dd><p>
2417 Connect pin 6 and pin 1 of the companion connector. Pin 1
2418 can be identified by the square pad around it, and then
2419 the pins could sequentially across the board. Be very
2420 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
2421 anything as that is connected directly to the battery. Pin
2422 7 carries 3.3V and the board will crash if that is
2423 connected to pin 1, but shouldn't damage the board.
2424 </p></dd><dt><span class="term">EasyMega</span></dt><dd><p>
2425 Connect pin 6 and pin 1 of the companion connector. Pin 1
2426 can be identified by the square pad around it, and then
2427 the pins could sequentially across the board. Be very
2428 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
2429 anything as that is connected directly to the battery. Pin
2430 7 carries 3.3V and the board will crash if that is
2431 connected to pin 1, but shouldn't damage the board.
2432 </p></dd><dt><span class="term">TeleMetrum v2</span></dt><dd><p>
2433 Connect pin 6 and pin 1 of the companion connector. Pin 1
2434 can be identified by the square pad around it, and then
2435 the pins could sequentially across the board. Be very
2436 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
2437 anything as that is connected directly to the battery. Pin
2438 7 carries 3.3V and the board will crash if that is
2439 connected to pin 1, but shouldn't damage the board.
2440 </p></dd><dt><span class="term">EasyMini</span></dt><dd><p>
2441 Connect pin 6 and pin 1 of the debug connector, which is
2442 the six holes next to the beeper. Pin 1 can be identified
2443 by the square pad around it, and then the pins could
2444 sequentially across the board, making Pin 6 the one on the
2445 other end of the row.
2446 </p></dd><dt><span class="term">TeleDongle v3</span></dt><dd><p>
2447 Connect pin 32 on the CPU to ground. Pin 32 is closest
2448 to the USB wires on the row of pins towards the center
2449 of the board. Ground is available on the capacitor
2450 next to it, on the end towards the USB wires.
2451 </p></dd></dl></div><p>
2452 Once you've located the right pins:
2453 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2454 Turn the altimeter power off.
2455 </p></li><li class="listitem"><p>
2457 </p></li><li class="listitem"><p>
2458 Connect the indicated terminals together with a short
2459 piece of wire. Take care not to accidentally connect
2461 </p></li><li class="listitem"><p>
2463 </p></li><li class="listitem"><p>
2464 Turn the board power on.
2465 </p></li><li class="listitem"><p>
2466 The board should now be visible over USB as 'AltosFlash'
2467 and be ready to receive firmware.
2468 </p></li><li class="listitem"><p>
2469 Once the board has been powered up, you can remove the
2471 </p></li></ol></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37824016"></a>2. Pair Programming</h2></div></div></div><p>
2472 The big concept to understand is that you have to use a
2473 TeleMetrum v1.0, TeleBT v1.0 or TeleDongle v0.2 as a
2474 programmer to update a pair programmed device. Due to limited
2475 memory resources in the cc1111, we don't support programming
2476 directly over USB for these devices.
2477 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37825472"></a>3. Updating TeleMetrum v1.x Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2478 Find the 'programming cable' that you got as part of the starter
2479 kit, that has a red 8-pin MicroMaTch connector on one end and a
2480 red 4-pin MicroMaTch connector on the other end.
2481 </p></li><li class="listitem"><p>
2482 Take the 2 screws out of the TeleDongle v0.2 or TeleBT v1.0
2483 case to get access to the circuit board.
2484 </p></li><li class="listitem"><p>
2485 Plug the 8-pin end of the programming cable to the
2486 matching connector on the TeleDongle v0.2 or TeleBT v1.0, and the 4-pin end to the
2487 matching connector on the TeleMetrum.
2488 Note that each MicroMaTch connector has an alignment pin that
2489 goes through a hole in the PC board when you have the cable
2491 </p></li><li class="listitem"><p>
2492 Attach a battery to the TeleMetrum board.
2493 </p></li><li class="listitem"><p>
2494 Plug the TeleDongle v0.2 or TeleBT v1.0 into your computer's USB port, and power
2496 </p></li><li class="listitem"><p>
2497 Run AltosUI, and select 'Flash Image' from the File menu.
2498 </p></li><li class="listitem"><p>
2499 Pick the TeleDongle v0.2 or TeleBT v1.0 device from the list, identifying it as the
2501 </p></li><li class="listitem"><p>
2502 Select the image you want put on the TeleMetrum, which should have a
2503 name in the form telemetrum-v1.2-1.0.0.ihx. It should be visible
2504 in the default directory, if not you may have to poke around
2505 your system to find it.
2506 </p></li><li class="listitem"><p>
2507 Make sure the configuration parameters are reasonable
2508 looking. If the serial number and/or RF configuration
2509 values aren't right, you'll need to change them.
2510 </p></li><li class="listitem"><p>
2511 Hit the 'OK' button and the software should proceed to flash
2512 the TeleMetrum with new firmware, showing a progress bar.
2513 </p></li><li class="listitem"><p>
2514 Confirm that the TeleMetrum board seems to have updated OK, which you
2515 can do by plugging in to it over USB and using a terminal program
2516 to connect to the board and issue the 'v' command to check
2518 </p></li><li class="listitem"><p>
2519 If something goes wrong, give it another try.
2520 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37838736"></a>4. Updating TeleMini Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2521 You'll need a special 'programming cable' to reprogram the
2522 TeleMini. You can make your own using an 8-pin MicroMaTch
2523 connector on one end and a set of four pins on the other.
2524 </p></li><li class="listitem"><p>
2525 Take the 2 screws out of the TeleDongle v0.2 or TeleBT v1.0 case to get access
2526 to the circuit board.
2527 </p></li><li class="listitem"><p>
2528 Plug the 8-pin end of the programming cable to the matching
2529 connector on the TeleDongle v0.2 or TeleBT v1.0, and the 4-pins into the holes
2530 in the TeleMini circuit board. Note that the MicroMaTch
2531 connector has an alignment pin that goes through a hole in
2532 the PC board when you have the cable oriented correctly, and
2533 that pin 1 on the TeleMini board is marked with a square pad
2534 while the other pins have round pads.
2535 </p></li><li class="listitem"><p>
2536 Attach a battery to the TeleMini board.
2537 </p></li><li class="listitem"><p>
2538 Plug the TeleDongle v0.2 or TeleBT v1.0 into your computer's USB port, and power
2540 </p></li><li class="listitem"><p>
2541 Run AltosUI, and select 'Flash Image' from the File menu.
2542 </p></li><li class="listitem"><p>
2543 Pick the TeleDongle v0.2 or TeleBT v1.0 device from the list, identifying it as the
2545 </p></li><li class="listitem"><p>
2546 Select the image you want put on the TeleMini, which should have a
2547 name in the form telemini-v1.0-1.0.0.ihx. It should be visible
2548 in the default directory, if not you may have to poke around
2549 your system to find it.
2550 </p></li><li class="listitem"><p>
2551 Make sure the configuration parameters are reasonable
2552 looking. If the serial number and/or RF configuration
2553 values aren't right, you'll need to change them.
2554 </p></li><li class="listitem"><p>
2555 Hit the 'OK' button and the software should proceed to flash
2556 the TeleMini with new firmware, showing a progress bar.
2557 </p></li><li class="listitem"><p>
2558 Confirm that the TeleMini board seems to have updated OK, which you
2559 can do by configuring it over the radio link through the TeleDongle, or
2560 letting it come up in “flight” mode and listening for telemetry.
2561 </p></li><li class="listitem"><p>
2562 If something goes wrong, give it another try.
2563 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37852352"></a>5. Updating TeleDongle v0.2 Firmware</h2></div></div></div><p>
2564 Updating TeleDongle v0.2 firmware is just like updating
2565 TeleMetrum v1.x or TeleMini
2566 firmware, but you use either a TeleMetrum v1.x, TeleDongle
2567 v0.2 or TeleBT v1.0 as the programmer.
2568 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2569 Find the 'programming cable' that you got as part of the starter
2570 kit, that has a red 8-pin MicroMaTch connector on one end and a
2571 red 4-pin MicroMaTch connector on the other end.
2572 </p></li><li class="listitem"><p>
2573 Find the USB cable that you got as part of the starter kit, and
2574 plug the “mini” end in to the mating connector on TeleMetrum
2575 v1.x, TeleDongle v0.2 or TeleBT v1.0.
2576 </p></li><li class="listitem"><p>
2577 Take the 2 screws out of the TeleDongle v0.2 or TeleBT v1.0 case to get access
2578 to the circuit board.
2579 </p></li><li class="listitem"><p>
2580 Plug the 8-pin end of the programming cable to the
2581 matching connector on the programmer, and the 4-pin end to the
2582 matching connector on the TeleDongle v0.2.
2583 Note that each MicroMaTch connector has an alignment pin that
2584 goes through a hole in the PC board when you have the cable
2586 </p></li><li class="listitem"><p>
2587 Attach a battery to the TeleMetrum v1.x board if you're using one.
2588 </p></li><li class="listitem"><p>
2589 Plug both the programmer and the TeleDongle into your computer's USB
2590 ports, and power up the programmer.
2591 </p></li><li class="listitem"><p>
2592 Run AltosUI, and select 'Flash Image' from the File menu.
2593 </p></li><li class="listitem"><p>
2594 Pick the programmer device from the list, identifying it as the
2596 </p></li><li class="listitem"><p>
2597 Select the image you want put on the TeleDongle v0.2, which should have a
2598 name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
2599 in the default directory, if not you may have to poke around
2600 your system to find it.
2601 </p></li><li class="listitem"><p>
2602 Make sure the configuration parameters are reasonable
2603 looking. If the serial number and/or RF configuration
2604 values aren't right, you'll need to change them. The
2606 serial number is on the “bottom” of the circuit board, and can
2607 usually be read through the translucent blue plastic case without
2608 needing to remove the board from the case.
2609 </p></li><li class="listitem"><p>
2610 Hit the 'OK' button and the software should proceed to flash
2611 the TeleDongle v0.2 with new firmware, showing a progress bar.
2612 </p></li><li class="listitem"><p>
2613 Confirm that the TeleDongle v0.2 board seems to have updated OK, which you
2614 can do by plugging in to it over USB and using a terminal program
2615 to connect to the board and issue the 'v' command to check
2616 the version, etc. Once you're happy, remove the programming cable
2617 and put the cover back on the TeleDongle v0.2.
2618 </p></li><li class="listitem"><p>
2619 If something goes wrong, give it another try.
2620 </p></li></ol></div><p>
2621 Be careful removing the programming cable from the locking 8-pin
2622 connector on TeleMetrum. You'll need a fingernail or perhaps a thin
2623 screwdriver or knife blade to gently pry the locking ears out
2624 slightly to extract the connector. We used a locking connector on
2625 TeleMetrum to help ensure that the cabling to companion boards
2626 used in a rocket don't ever come loose accidentally in flight.
2627 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp37869568"></a>Chapter 11. Hardware Specifications</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp37870208">1.
2628 TeleMega Specifications
2629 </a></span></dt><dt><span class="section"><a href="#idp37881680">2.
2630 EasyMega Specifications
2631 </a></span></dt><dt><span class="section"><a href="#idp37891424">3.
2632 TeleMetrum v2 Specifications
2633 </a></span></dt><dt><span class="section"><a href="#idp37901984">4. TeleMetrum v1 Specifications</a></span></dt><dt><span class="section"><a href="#idp37912544">5.
2634 TeleMini v2.0 Specifications
2635 </a></span></dt><dt><span class="section"><a href="#idp37921376">6.
2636 TeleMini v1.0 Specifications
2637 </a></span></dt><dt><span class="section"><a href="#idp37930176">7.
2638 EasyMini Specifications
2639 </a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37870208"></a>1.
2640 TeleMega Specifications
2641 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2642 Recording altimeter for model rocketry.
2643 </p></li><li class="listitem"><p>
2644 Supports dual deployment and four auxiliary pyro channels
2645 (a total of 6 events).
2646 </p></li><li class="listitem"><p>
2647 70cm 40mW ham-band transceiver for telemetry down-link.
2648 </p></li><li class="listitem"><p>
2649 Barometric pressure sensor good to 100k feet MSL.
2650 </p></li><li class="listitem"><p>
2651 1-axis high-g accelerometer for motor characterization, capable of
2653 </p></li><li class="listitem"><p>
2654 9-axis IMU including integrated 3-axis accelerometer,
2655 3-axis gyroscope and 3-axis magnetometer.
2656 </p></li><li class="listitem"><p>
2657 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
2658 </p></li><li class="listitem"><p>
2659 On-board 8 Megabyte non-volatile memory for flight data storage.
2660 </p></li><li class="listitem"><p>
2661 USB interface for battery charging, configuration, and data recovery.
2662 </p></li><li class="listitem"><p>
2663 Fully integrated support for Li-Po rechargeable batteries.
2664 </p></li><li class="listitem"><p>
2665 Can use either main system Li-Po or optional separate pyro battery
2667 </p></li><li class="listitem"><p>
2668 3.25 x 1.25 inch board designed to fit inside 38mm air-frame coupler tube.
2669 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37881680"></a>2.
2670 EasyMega Specifications
2671 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2672 Recording altimeter for model rocketry.
2673 </p></li><li class="listitem"><p>
2674 Supports dual deployment and four auxiliary pyro channels
2675 (a total of 6 events).
2676 </p></li><li class="listitem"><p>
2677 Barometric pressure sensor good to 100k feet MSL.
2678 </p></li><li class="listitem"><p>
2679 1-axis high-g accelerometer for motor characterization, capable of
2681 </p></li><li class="listitem"><p>
2682 9-axis IMU including integrated 3-axis accelerometer,
2683 3-axis gyroscope and 3-axis magnetometer.
2684 </p></li><li class="listitem"><p>
2685 On-board 8 Megabyte non-volatile memory for flight data storage.
2686 </p></li><li class="listitem"><p>
2687 USB interface for battery charging, configuration, and data recovery.
2688 </p></li><li class="listitem"><p>
2689 Fully integrated support for Li-Po rechargeable batteries.
2690 </p></li><li class="listitem"><p>
2691 Can use either main system Li-Po or optional separate pyro battery
2693 </p></li><li class="listitem"><p>
2694 1.25 x 1.25 inch board designed to fit inside 38mm air-frame coupler tube.
2695 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37891424"></a>3.
2696 TeleMetrum v2 Specifications
2697 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2698 Recording altimeter for model rocketry.
2699 </p></li><li class="listitem"><p>
2700 Supports dual deployment (can fire 2 ejection charges).
2701 </p></li><li class="listitem"><p>
2702 70cm, 40mW ham-band transceiver for telemetry down-link.
2703 </p></li><li class="listitem"><p>
2704 Barometric pressure sensor good to 100k feet MSL.
2705 </p></li><li class="listitem"><p>
2706 1-axis high-g accelerometer for motor characterization, capable of
2708 </p></li><li class="listitem"><p>
2709 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
2710 </p></li><li class="listitem"><p>
2711 On-board 8 Megabyte non-volatile memory for flight data storage.
2712 </p></li><li class="listitem"><p>
2713 USB interface for battery charging, configuration, and data recovery.
2714 </p></li><li class="listitem"><p>
2715 Fully integrated support for Li-Po rechargeable batteries.
2716 </p></li><li class="listitem"><p>
2717 Uses Li-Po to fire e-matches, can be modified to support
2718 optional separate pyro battery if needed.
2719 </p></li><li class="listitem"><p>
2720 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
2721 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37901984"></a>4. TeleMetrum v1 Specifications</h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2722 Recording altimeter for model rocketry.
2723 </p></li><li class="listitem"><p>
2724 Supports dual deployment (can fire 2 ejection charges).
2725 </p></li><li class="listitem"><p>
2726 70cm, 10mW ham-band transceiver for telemetry down-link.
2727 </p></li><li class="listitem"><p>
2728 Barometric pressure sensor good to 45k feet MSL.
2729 </p></li><li class="listitem"><p>
2730 1-axis high-g accelerometer for motor characterization, capable of
2731 +/- 50g using default part.
2732 </p></li><li class="listitem"><p>
2733 On-board, integrated GPS receiver with 5Hz update rate capability.
2734 </p></li><li class="listitem"><p>
2735 On-board 1 megabyte non-volatile memory for flight data storage.
2736 </p></li><li class="listitem"><p>
2737 USB interface for battery charging, configuration, and data recovery.
2738 </p></li><li class="listitem"><p>
2739 Fully integrated support for Li-Po rechargeable batteries.
2740 </p></li><li class="listitem"><p>
2741 Uses Li-Po to fire e-matches, can be modified to support
2742 optional separate pyro battery if needed.
2743 </p></li><li class="listitem"><p>
2744 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
2745 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37912544"></a>5.
2746 TeleMini v2.0 Specifications
2747 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2748 Recording altimeter for model rocketry.
2749 </p></li><li class="listitem"><p>
2750 Supports dual deployment (can fire 2 ejection charges).
2751 </p></li><li class="listitem"><p>
2752 70cm, 10mW ham-band transceiver for telemetry down-link.
2753 </p></li><li class="listitem"><p>
2754 Barometric pressure sensor good to 100k feet MSL.
2755 </p></li><li class="listitem"><p>
2756 On-board 1 megabyte non-volatile memory for flight data storage.
2757 </p></li><li class="listitem"><p>
2758 USB interface for configuration, and data recovery.
2759 </p></li><li class="listitem"><p>
2760 Support for Li-Po rechargeable batteries (using an
2761 external charger), or any 3.7-15V external battery.
2762 </p></li><li class="listitem"><p>
2763 Uses Li-Po to fire e-matches, can be modified to support
2764 optional separate pyro battery if needed.
2765 </p></li><li class="listitem"><p>
2766 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
2767 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37921376"></a>6.
2768 TeleMini v1.0 Specifications
2769 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2770 Recording altimeter for model rocketry.
2771 </p></li><li class="listitem"><p>
2772 Supports dual deployment (can fire 2 ejection charges).
2773 </p></li><li class="listitem"><p>
2774 70cm, 10mW ham-band transceiver for telemetry down-link.
2775 </p></li><li class="listitem"><p>
2776 Barometric pressure sensor good to 45k feet MSL.
2777 </p></li><li class="listitem"><p>
2778 On-board 5 kilobyte non-volatile memory for flight data storage.
2779 </p></li><li class="listitem"><p>
2780 RF interface for configuration, and data recovery.
2781 </p></li><li class="listitem"><p>
2782 Support for Li-Po rechargeable batteries, using an external charger.
2783 </p></li><li class="listitem"><p>
2784 Uses Li-Po to fire e-matches, can be modified to support
2785 optional separate pyro battery if needed.
2786 </p></li><li class="listitem"><p>
2787 1.5 x .5 inch board designed to fit inside 18mm air-frame coupler tube.
2788 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37930176"></a>7.
2789 EasyMini Specifications
2790 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2791 Recording altimeter for model rocketry.
2792 </p></li><li class="listitem"><p>
2793 Supports dual deployment (can fire 2 ejection charges).
2794 </p></li><li class="listitem"><p>
2795 Barometric pressure sensor good to 100k feet MSL.
2796 </p></li><li class="listitem"><p>
2797 On-board 1 megabyte non-volatile memory for flight data storage.
2798 </p></li><li class="listitem"><p>
2799 USB interface for configuration, and data recovery.
2800 </p></li><li class="listitem"><p>
2801 Support for Li-Po rechargeable batteries (using an
2802 external charger), or any 3.7-15V external battery.
2803 </p></li><li class="listitem"><p>
2804 Uses Li-Po to fire e-matches, can be modified to support
2805 optional separate pyro battery if needed.
2806 </p></li><li class="listitem"><p>
2807 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
2808 </p></li></ul></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp37938288"></a>Chapter 12. FAQ</h1></div></div></div><p>
2809 <span class="emphasis"><em>TeleMetrum seems to shut off when disconnected from the
2810 computer.</em></span>
2811 Make sure the battery is adequately charged. Remember the
2812 unit will pull more power than the USB port can deliver before the
2813 GPS enters “locked” mode. The battery charges best when TeleMetrum
2816 <span class="emphasis"><em>It's impossible to stop the TeleDongle when it's in “p” mode, I have
2817 to unplug the USB cable? </em></span>
2818 Make sure you have tried to “escape out” of
2819 this mode. If this doesn't work the reboot procedure for the
2820 TeleDongle *is* to simply unplug it. 'cu' however will retain it's
2821 outgoing buffer IF your “escape out” ('~~') does not work.
2822 At this point using either 'ao-view' (or possibly
2823 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
2826 <span class="emphasis"><em>The amber LED (on the TeleMetrum) lights up when both
2827 battery and USB are connected. Does this mean it's charging?
2829 Yes, the yellow LED indicates the charging at the 'regular' rate.
2830 If the led is out but the unit is still plugged into a USB port,
2831 then the battery is being charged at a 'trickle' rate.
2833 <span class="emphasis"><em>There are no “dit-dah-dah-dit” sound or lights like the manual
2834 mentions?</em></span>
2835 That's the “pad” mode. Weak batteries might be the problem.
2836 It is also possible that the flight computer is horizontal and the
2838 is instead a “dit-dit” meaning 'idle'. For TeleMini, it's possible that
2839 it received a command packet which would have left it in “pad” mode.
2841 <span class="emphasis"><em>How do I save flight data?</em></span>
2842 Live telemetry is written to file(s) whenever AltosUI is connected
2843 to the TeleDongle. The file area defaults to ~/TeleMetrum
2844 but is easily changed using the menus in AltosUI. The files that
2845 are written end in '.telem'. The after-flight
2846 data-dumped files will end in .eeprom and represent continuous data
2847 unlike the .telem files that are subject to losses
2848 along the RF data path.
2849 See the above instructions on what and how to save the eeprom stored
2850 data after physically retrieving your altimeter. Make sure to save
2851 the on-board data after each flight; while the TeleMetrum can store
2852 multiple flights, you never know when you'll lose the altimeter...
2853 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp37947888"></a>Appendix A. Notes for Older Software</h1></div></div></div><p>
2854 <span class="emphasis"><em>
2855 Before AltosUI was written, using Altus Metrum devices required
2856 some finesse with the Linux command line. There was a limited
2857 GUI tool, ao-view, which provided functionality similar to the
2858 Monitor Flight window in AltosUI, but everything else was a
2859 fairly 80's experience. This appendix includes documentation for
2860 using that software.
2863 Both TeleMetrum and TeleDongle can be directly communicated
2864 with using USB ports. The first thing you should try after getting
2865 both units plugged into to your computer's USB port(s) is to run
2866 'ao-list' from a terminal-window to see what port-device-name each
2867 device has been assigned by the operating system.
2868 You will need this information to access the devices via their
2869 respective on-board firmware and data using other command line
2870 programs in the AltOS software suite.
2872 TeleMini can be communicated with through a TeleDongle device
2873 over the radio link. When first booted, TeleMini listens for a
2874 TeleDongle device and if it receives a packet, it goes into
2875 'idle' mode. Otherwise, it goes into 'pad' mode and waits to be
2876 launched. The easiest way to get it talking is to start the
2877 communication link on the TeleDongle and the power up the
2880 To access the device's firmware for configuration you need a terminal
2881 program such as you would use to talk to a modem. The software
2882 authors prefer using the program 'cu' which comes from the UUCP package
2883 on most Unix-like systems such as Linux. An example command line for
2884 cu might be 'cu -l /dev/ttyACM0', substituting the correct number
2885 indicated from running the
2886 ao-list program. Another reasonable terminal program for Linux is
2887 'cutecom'. The default 'escape'
2888 character used by CU (i.e. the character you use to
2889 issue commands to cu itself instead of sending the command as input
2890 to the connected device) is a '~'. You will need this for use in
2891 only two different ways during normal operations. First is to exit
2892 the program by sending a '~.' which is called a 'escape-disconnect'
2893 and allows you to close-out from 'cu'. The
2894 second use will be outlined later.
2896 All of the Altus Metrum devices share the concept of a two level
2897 command set in their firmware.
2898 The first layer has several single letter commands. Once
2899 you are using 'cu' (or 'cutecom') sending (typing) a '?'
2900 returns a full list of these
2901 commands. The second level are configuration sub-commands accessed
2902 using the 'c' command, for
2903 instance typing 'c?' will give you this second level of commands
2904 (all of which require the
2905 letter 'c' to access). Please note that most configuration options
2906 are stored only in Flash memory; TeleDongle doesn't provide any storage
2907 for these options and so they'll all be lost when you unplug it.
2909 Try setting these configuration ('c' or second level menu) values. A good
2910 place to start is by setting your call sign. By default, the boards
2911 use 'N0CALL' which is cute, but not exactly legal!
2912 Spend a few minutes getting comfortable with the units, their
2913 firmware, and 'cu' (or possibly 'cutecom').
2914 For instance, try to send
2915 (type) a 'c r 2' and verify the channel change by sending a 'c s'.
2916 Verify you can connect and disconnect from the units while in your
2917 terminal program by sending the escape-disconnect mentioned above.
2919 To set the radio frequency, use the 'c R' command to specify the
2920 radio transceiver configuration parameter. This parameter is computed
2921 using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
2922 the standard calibration reference frequency, 'S', (normally 434.550MHz):
2923 </p><pre class="programlisting">
2926 Round the result to the nearest integer value.
2927 As with all 'c' sub-commands, follow this with a 'c w' to write the
2928 change to the parameter block in the on-board flash on
2929 your altimeter board if you want the change to stay in place across reboots.
2931 To set the apogee delay, use the 'c d' command.
2932 As with all 'c' sub-commands, follow this with a 'c w' to write the
2933 change to the parameter block in the on-board DataFlash chip.
2935 To set the main deployment altitude, use the 'c m' command.
2936 As with all 'c' sub-commands, follow this with a 'c w' to write the
2937 change to the parameter block in the on-board DataFlash chip.
2939 To calibrate the radio frequency, connect the UHF antenna port to a
2940 frequency counter, set the board to 434.550MHz, and use the 'C'
2941 command to generate a CW carrier. Wait for the transmitter temperature
2942 to stabilize and the frequency to settle down.
2943 Then, divide 434.550 MHz by the
2944 measured frequency and multiply by the current radio cal value show
2945 in the 'c s' command. For an unprogrammed board, the default value
2946 is 1186611 for cc1111 based products and 7119667 for cc1120
2947 based products. Take the resulting integer and program it using the 'c f'
2948 command. Testing with the 'C' command again should show a carrier
2949 within a few tens of Hertz of the intended frequency.
2950 As with all 'c' sub-commands, follow this with a 'c w' to write the
2951 change to the configuration memory.
2953 Note that the 'reboot' command, which is very useful on the altimeters,
2954 will likely just cause problems with the dongle. The *correct* way
2955 to reset the dongle is just to unplug and re-plug it.
2957 A fun thing to do at the launch site and something you can do while
2958 learning how to use these units is to play with the radio link access
2959 between an altimeter and the TeleDongle. Be aware that you *must* create
2960 some physical separation between the devices, otherwise the link will
2961 not function due to signal overload in the receivers in each device.
2963 Now might be a good time to take a break and read the rest of this
2964 manual, particularly about the two “modes” that the altimeters
2965 can be placed in. TeleMetrum uses the position of the device when booting
2966 up will determine whether the unit is in “pad” or “idle” mode. TeleMini
2967 enters “idle” mode when it receives a command packet within the first 5 seconds
2968 of being powered up, otherwise it enters “pad” mode.
2970 You can access an altimeter in idle mode from the TeleDongle's USB
2971 connection using the radio link
2972 by issuing a 'p' command to the TeleDongle. Practice connecting and
2973 disconnecting ('~~' while using 'cu') from the altimeter. If
2974 you cannot escape out of the “p” command, (by using a '~~' when in
2975 CU) then it is likely that your kernel has issues. Try a newer version.
2977 Using this radio link allows you to configure the altimeter, test
2978 fire e-matches and igniters from the flight line, check pyro-match
2979 continuity and so forth. You can leave the unit turned on while it
2980 is in 'idle mode' and then place the
2981 rocket vertically on the launch pad, walk away and then issue a
2982 reboot command. The altimeter will reboot and start sending data
2983 having changed to the “pad” mode. If the TeleDongle is not receiving
2984 this data, you can disconnect 'cu' from the TeleDongle using the
2985 procedures mentioned above and THEN connect to the TeleDongle from
2986 inside 'ao-view'. If this doesn't work, disconnect from the
2987 TeleDongle, unplug it, and try again after plugging it back in.
2989 In order to reduce the chance of accidental firing of pyrotechnic
2990 charges, the command to fire a charge is intentionally somewhat
2991 difficult to type, and the built-in help is slightly cryptic to
2992 prevent accidental echoing of characters from the help text back at
2993 the board from firing a charge. The command to fire the apogee
2994 drogue charge is 'i DoIt drogue' and the command to fire the main
2995 charge is 'i DoIt main'.
2997 On TeleMetrum, the GPS will eventually find enough satellites, lock in on them,
2998 and 'ao-view' will both auditorily announce and visually indicate
3000 Now you can launch knowing that you have a good data path and
3001 good satellite lock for flight data and recovery. Remember
3002 you MUST tell ao-view to connect to the TeleDongle explicitly in
3003 order for ao-view to be able to receive data.
3005 The altimeters provide RDF (radio direction finding) tones on
3006 the pad, during descent and after landing. These can be used to
3007 locate the rocket using a directional antenna; the signal
3008 strength providing an indication of the direction from receiver to rocket.
3010 TeleMetrum also provides GPS tracking data, which can further simplify
3011 locating the rocket once it has landed. (The last good GPS data
3012 received before touch-down will be on the data screen of 'ao-view'.)
3014 Once you have recovered the rocket you can download the eeprom
3015 contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
3016 either a USB cable or over the radio link using TeleDongle.
3017 And by following the man page for 'ao-postflight' you can create
3018 various data output reports, graphs, and even KML data to see the
3019 flight trajectory in Google-earth. (Moving the viewing angle making
3020 sure to connect the yellow lines while in Google-earth is the proper
3023 As for ao-view.... some things are in the menu but don't do anything
3024 very useful. The developers have stopped working on ao-view to focus
3025 on a new, cross-platform ground station program. So ao-view may or
3026 may not be updated in the future. Mostly you just use
3027 the Log and Device menus. It has a wonderful display of the incoming
3028 flight data and I am sure you will enjoy what it has to say to you
3029 once you enable the voice output!
3030 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp37969232"></a>Appendix B. Drill Templates</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp37970400">1. TeleMega template</a></span></dt><dt><span class="section"><a href="#idp37987088">2. EasyMega template</a></span></dt><dt><span class="section"><a href="#idp37991472">3. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp37995856">4. TeleMini v2/EasyMini template</a></span></dt><dt><span class="section"><a href="#idp38000256">5. TeleMini v1 template</a></span></dt></dl></div><p>
3031 These images, when printed, provide precise templates for the
3032 mounting holes in Altus Metrum flight computers
3033 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37970400"></a>1. TeleMega template</h2></div></div></div><p>
3034 TeleMega has overall dimensions of 1.250 x 3.250 inches, and
3035 the mounting holes are sized for use with 4-40 or M3 screws.
3036 </p><div class="informalfigure"><div class="mediaobject" align="center"><a name="TeleMegaTemplate"></a><object type="image/svg+xml" data="telemega.svg" align="middle"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37987088"></a>2. EasyMega template</h2></div></div></div><p>
3037 EasyMega has overall dimensions of 1.250 x 2.250 inches, and
3038 the mounting holes are sized for use with 4-40 or M3 screws.
3039 </p><div class="informalfigure"><div class="mediaobject" align="center"><a name="EasyMegaTemplate"></a><object type="image/svg+xml" data="easymega.svg" align="middle"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37991472"></a>3. TeleMetrum template</h2></div></div></div><p>
3040 TeleMetrum has overall dimensions of 1.000 x 2.750 inches, and the
3041 mounting holes are sized for use with 4-40 or M3 screws.
3042 </p><div class="informalfigure"><div class="mediaobject" align="center"><a name="TeleMetrumTemplate"></a><object type="image/svg+xml" data="telemetrum.svg" align="middle"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp37995856"></a>4. TeleMini v2/EasyMini template</h2></div></div></div><p>
3043 TeleMini v2 and EasyMini have overall dimensions of 0.800 x 1.500 inches, and the
3044 mounting holes are sized for use with 4-40 or M3 screws.
3045 </p><div class="informalfigure"><div class="mediaobject" align="center"><a name="MiniTemplate"></a><object type="image/svg+xml" data="easymini.svg" align="middle"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38000256"></a>5. TeleMini v1 template</h2></div></div></div><p>
3046 TeleMini has overall dimensions of 0.500 x 1.500 inches, and the
3047 mounting holes are sized for use with 2-56 or M2 screws.
3048 </p><div class="informalfigure"><div class="mediaobject" align="center"><a name="TeleMiniTemplate"></a><object type="image/svg+xml" data="telemini.svg" align="middle"></object></div></div></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp38004768"></a>Appendix C. Calibration</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp38006320">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp38011520">2. TeleMetrum, TeleMega and EasyMega Accelerometers</a></span></dt></dl></div><p>
3049 There are only two calibrations required for TeleMetrum and
3050 TeleMega, and only one for EasyMega, TeleDongle, TeleMini and EasyMini.
3051 All boards are shipped from the factory pre-calibrated, but
3052 the procedures are documented here in case they are ever
3053 needed. Re-calibration is not supported by AltosUI, you must
3054 connect to the board with a serial terminal program and
3055 interact directly with the on-board command interpreter to
3057 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38006320"></a>1. Radio Frequency</h2></div></div></div><p>
3058 The radio frequency is synthesized from a clock based on the
3059 crystal on the board. The actual frequency of this oscillator
3060 must be measured to generate a calibration constant. While our
3062 bandwidth is wide enough to allow boards to communicate even when
3063 their oscillators are not on exactly the same frequency, performance
3064 is best when they are closely matched.
3065 Radio frequency calibration requires a calibrated frequency counter.
3066 Fortunately, once set, the variation in frequency due to aging and
3067 temperature changes is small enough that re-calibration by customers
3068 should generally not be required.
3070 To calibrate the radio frequency, connect the UHF antenna
3071 port to a frequency counter, set the board to 434.550MHz,
3072 and use the 'C' command in the on-board command interpreter
3073 to generate a CW carrier. For USB-enabled boards, this is
3074 best done over USB. For TeleMini v1, note that the only way
3075 to escape the 'C' command is via power cycle since the board
3076 will no longer be listening for commands once it starts
3077 generating a CW carrier.
3079 Wait for the transmitter temperature to stabilize and the frequency
3080 to settle down. Then, divide 434.550 MHz by the
3081 measured frequency and multiply by the current radio cal value show
3082 in the 'c s' command. For an unprogrammed board, the default value
3083 is 1186611. Take the resulting integer and program it using the 'c f'
3084 command. Testing with the 'C' command again should show a carrier
3085 within a few tens of Hertz of the intended frequency.
3086 As with all 'c' sub-commands, follow this with a 'c w' to write the
3087 change to the parameter block in the on-board storage chip.
3089 Note that any time you re-do the radio frequency calibration, the
3090 radio frequency is reset to the default 434.550 Mhz. If you want
3091 to use another frequency, you will have to set that again after
3092 calibration is completed.
3093 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38011520"></a>2. TeleMetrum, TeleMega and EasyMega Accelerometers</h2></div></div></div><p>
3094 While barometric sensors are factory-calibrated,
3095 accelerometers are not, and so each must be calibrated once
3096 installed in a flight computer. Explicitly calibrating the
3097 accelerometers also allows us to load any compatible device.
3098 We perform a two-point calibration using gravity.
3100 To calibrate the acceleration sensor, use the 'c a 0' command. You
3101 will be prompted to orient the board vertically with the UHF antenna
3102 up and press a key, then to orient the board vertically with the
3103 UHF antenna down and press a key. Note that the accuracy of this
3104 calibration depends primarily on how perfectly vertical and still
3105 the board is held during the cal process. As with all 'c'
3106 sub-commands, follow this with a 'c w' to write the
3107 change to the parameter block in the on-board DataFlash chip.
3109 The +1g and -1g calibration points are included in each telemetry
3110 frame and are part of the header stored in onboard flash to be
3111 downloaded after flight. We always store and return raw ADC
3112 samples for each sensor... so nothing is permanently “lost” or
3113 “damaged” if the calibration is poor.
3115 In the unlikely event an accel cal goes badly, it is possible
3116 that TeleMetrum, TeleMega or EasyMega may always come up in 'pad mode'
3117 and as such not be listening to either the USB or radio link.
3118 If that happens, there is a special hook in the firmware to
3119 force the board back in to 'idle mode' so you can re-do the
3120 cal. To use this hook, you just need to ground the SPI clock
3121 pin at power-on. This pin is available as pin 2 on the 8-pin
3122 companion connector, and pin 1 is ground. So either
3123 carefully install a fine-gauge wire jumper between the two
3124 pins closest to the index hole end of the 8-pin connector, or
3125 plug in the programming cable to the 8-pin connector and use
3126 a small screwdriver or similar to short the two pins closest
3127 to the index post on the 4-pin end of the programming cable,
3128 and power up the board. It should come up in 'idle mode'
3129 (two beeps), allowing a re-cal.
3130 </p></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp38016624"></a>Appendix D. Igniter Current</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp38017888">1. Current Products</a></span></dt><dt><span class="section"><a href="#idp38021328">2. Version 1 Products</a></span></dt></dl></div><p>
3131 The question "how much igniter current can Altus Metrum products
3132 handle?" comes up fairly frequently. The short answer is "more than
3133 you're likely to need", the remainder of this appendix provides a
3135 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38017888"></a>1. Current Products</h2></div></div></div><p>
3136 The FET switches we're using on all of our current products that
3137 have pyro channels are the Vishay Siliconix Si7232DN. These parts
3138 have exceptionally low Rds(on) values, better than 0.02 ohms! That
3139 means they aren't making a lot of heat... and the limit on current
3140 is "package limited", meaning it's all about how much you can heat
3141 the die before something breaks.
3143 Cutting to the chase, the Si7232DN specs are 25 amps <span class="emphasis"><em>continuous</em></span> at
3144 20V at a temperature of 25C. In pulsed mode, they're rated for 40A.
3145 However, those specs are a little mis-leading because it really is
3146 all about the heat generated... you can get something like 85A
3147 through one briefly. Note that a typical commercial e-match only
3148 needed about 13 microseconds to fire in tests on my bench a couple
3151 So a great plan is to use something like an e-match as the initiator
3152 and build up pyrogen(s) as required to actually light what you're
3153 trying to light... But if you want to use a high-current igniter,
3154 we can probably handle it!
3155 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38021328"></a>2. Version 1 Products</h2></div></div></div><p>
3156 The FET switches used on TeleMetrum v1 and TeleMini v1 products
3157 were Fairchild FDS9926A. The Rds(on) values under our operating
3158 conditions are on the order of 0.04 ohms. These parts were rated
3159 for a continuous current-carrying capacity of 6.5A, and a pulsed
3160 current capacity of 20A.
3162 As with the more modern parts, the real limit is based on the heat
3163 generated in the part during the firing interval. So, while the
3164 specs on these parts aren't as good as the ones we use on current
3165 products, they were still great, and we never had a complaint about
3166 current carrying capacity with any of our v1 boards.
3167 </p></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp38023664"></a>Appendix E. Release Notes</h1></div></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38024304"></a>Version 1.6</h2></div></div></div><p>
3168 Version 1.6 includes support for our updated TeleDongle v3.0
3169 product and bug fixes in in the flight software for all our boards
3170 and ground station interfaces.
3173 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3174 Add support for TeleDongle v3.0 boards.
3175 </p></li></ul></div><p>
3178 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3179 Don't beep out the continuity twice by accident in idle mode.
3180 If the battery voltage report takes longer than the initialiation
3181 sequence, the igniter continuity would get reported twice.
3182 </p></li><li class="listitem"><p>
3183 Record all 32 bits of gyro calibration data in TeleMega and
3184 EasyMega log files. This fixes computation of the gyro rates
3186 </p></li><li class="listitem"><p>
3187 Change TeleDongle LED usage. Green LED flashes when valid
3188 packet is received. Red LED flashes when invalid packet is
3190 </p></li><li class="listitem"><p>
3191 Replace LPC11U14 SPI driver with non-interrupt version. The
3192 interrupt code would occasionally wedge on long transfers
3193 if interrupts were blocked for too long. This affects all
3194 released TeleGPS products; if you have a TeleGPS device,
3195 you'll want to reflash the firmware.
3196 </p></li></ul></div><p>
3198 AltosUI and TeleGPS New Features
3199 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3200 Compute tilt angle from TeleMega and EasyMega log
3201 files. This duplicates the quaternion-based angle tracking
3202 code from the flight firmware inside the ground station
3203 software so that post-flight analysis can include evaluation
3205 </p></li><li class="listitem"><p>
3206 Shows the tool button window when starting with a data file
3207 specified. This means that opening a data file from the file
3208 manager will now bring up the main window to let you operate
3209 the whole application.
3210 </p></li></ul></div><p>
3213 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3214 Show the 'Connecting' dialog when using Monitor Idle. Lets
3215 you cancel the Monitor Idle startup when connecting over the
3217 </p></li><li class="listitem"><p>
3218 Make 'Monitor Idle' work for TeleGPS devices when connected
3219 over USB. It's nice for testing without needing to broadcast
3221 </p></li><li class="listitem"><p>
3222 Use different Windows API to discover USB devices. This
3223 works better on my Windows 7 box, and will be used if the
3224 older API fails to provide the necessary information.
3225 </p></li><li class="listitem"><p>
3226 Look in more places in the registry to try and identify the
3227 installed Java version on Windows. If you install the
3228 default 32-bit version of Windows on a 64-bit OS, the Java
3229 registry information is hiding \SOFTWARE\Wow6432Node for
3231 </p></li><li class="listitem"><p>
3232 Fix file association on Windows by searching for the
3233 javaw.exe program instead of assuming it is in
3234 %SYSTEMROOT%. This makes double-clicking on Altus Metrum
3235 data files in the file manager work correctly.
3236 </p></li><li class="listitem"><p>
3237 When replaying a file, put 'done' in the Age field when we
3238 reach the end of the file, instead of continuing to count forever.
3239 </p></li><li class="listitem"><p>
3240 In the Scan Channels code, wait for five seconds if we see
3241 any packet. This is needed because AltOS now sends the
3242 callsign, serial number and flight number only once every
3243 five seconds these days.
3244 </p></li><li class="listitem"><p>
3245 In the Scan Channels code, reset pending flight state
3246 information each time we change channels. This avoids having
3247 flight computers appear on multiple frequencies by accident.
3248 </p></li></ul></div><p>
3249 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38025904"></a>Version 1.5</h2></div></div></div><p>
3250 Version 1.5 is a major release. It includes support for our new
3251 EasyMega product, new features and bug fixes in in the flight
3252 software for all our boards and the AltosUI ground station
3255 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3256 Add support for EasyMega boards.
3257 </p></li><li class="listitem"><p>
3258 Make the APRS SSID be configurable. This lets you track
3259 different rockets on the same receiver without getting
3261 </p></li><li class="listitem"><p>
3262 Report extra pyro channel continuity state on EasyMega and
3263 TeleMega via the beeper. This lets you easily verify flight
3264 readiness on these boards after powering up the electronics
3266 </p></li><li class="listitem"><p>
3267 Add lower telemetry data rates (2400 and 9600 bps) to
3268 increase telemetry radio range. This reduces the amount of
3269 data received as well as increasing battery consumption in
3271 </p></li><li class="listitem"><p>
3272 Change TeleGPS to have only a single log, and append new
3273 data to it rather than using seperate per-flight logs. This
3274 avoids accidentally filling up log storage by turning
3275 TeleGPS on/off several times.
3276 </p></li></ul></div><p>
3279 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3280 Increase the maximum range for altitude values from +/-32767m
3281 to +/-2147483647m, allowing the flight computers to function
3282 correctly above the 32km level.
3283 </p></li><li class="listitem"><p>
3284 Continuously test pyro firing conditions during delay stage,
3285 inhibiting the pyro channel if the test fails. This prevents
3286 firing pyro charges where the conditions were good before
3287 the delay, but become bad before the delay expires.
3288 </p></li><li class="listitem"><p>
3289 Allow negative numbers in pyro configuration values. This
3290 lets you specify things like descending speed or
3292 </p></li></ul></div><p>
3294 AltosUI and TeleGPS New Features
3295 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3296 Support telemetry baud rate selection. Adds menus to
3297 the flight monitoring and configuration for baud rate
3299 </p></li><li class="listitem"><p>
3300 Support APRS SSID configuration.
3301 </p></li><li class="listitem"><p>
3302 Integrate with file managers. This provides icons for all of
3303 our file types and associates our application with the files
3304 so that using a file manager to open a AltOS data file
3305 results in launching our application.
3306 </p></li></ul></div><p>
3309 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3310 Make the 'Graph' button on the landed tab work again.
3311 </p></li><li class="listitem"><p>
3312 Make tests for Java on Windows a bit smarter, and also
3313 provide the user with the option to skip installing Java for
3314 cases where we just can't figure out what version is installed.
3315 </p></li></ul></div><p>
3316 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38027504"></a>Version 1.4.1</h2></div></div></div><p>
3317 Version 1.4.1 is a minor release. It fixes install issues on
3318 Windows and provides the missing TeleMetrum V2.0 firmware. There
3319 aren't any changes to the firmware or host applications at
3320 all. All Windows users will want to upgrade to get the signed
3321 driver, but Mac and Linux users who do not need the TeleMetrum
3322 V2.0 firmware image will not need to upgrade.
3324 Windows Install Fixes
3325 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3326 Provide signed Windows driver files. This should avoid any need to
3327 disable driver signature checking on Windows 7 or 8.
3328 </p></li><li class="listitem"><p>
3329 Fix Java version detection and download. Previously, the
3330 installer would only look for Java 6 or 7 and insist on
3331 downloading its own Java bits if there was something else
3332 installed. Furthermore, the 64-bit Java link provided didn't
3333 work for anyone other than Keith, making it impossible to
3334 install AltOS on any machine with Java SE 8 installed.
3335 </p></li></ul></div><p>
3338 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3339 Include 1.4 firmware for TeleMetrum V2.0. None of the
3340 installers shipped this file. Now it's included in the AltOS
3341 packages for Linux, Mac and Windows.
3342 </p></li><li class="listitem"><p>
3343 Include Google Application Key for map downloading. The 1.4
3344 release didn't have this key in the released version of the
3345 software, making map downloading fail for most people.
3346 </p></li></ul></div><p>
3347 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38029008"></a>Version 1.4</h2></div></div></div><p>
3348 Version 1.4 is a major release. It includes support for our new
3349 TeleGPS product, new features and bug fixes in in the flight
3350 software for all our boards and the AltosUI ground station
3353 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3354 Add support for TeleGPS boards.
3355 </p></li><li class="listitem"><p>
3356 Replace the 'dit dit dit' tones at startup with the current
3357 battery voltage, measured in tenths of a volt. This lets you
3358 check the battery voltage without needing telemetry, which
3359 is especially useful on EasyMini.
3360 </p></li><li class="listitem"><p>
3361 Change state beeping to "Farnsworth spacing", which means
3362 they're quite a bit faster than before, and so they take
3364 </p></li><li class="listitem"><p>
3365 Make the beeper tone configurable, making it possible to
3366 distinguish between two Altus Metrum products in the same ebay.
3367 </p></li><li class="listitem"><p>
3368 Make the firing time for extra pyro channels configurable,
3369 allowing longer (or shorter) than the default 50ms. Only relevant
3370 for TeleMega at this time.
3371 </p></li></ul></div><p>
3374 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3375 Fix bug preventing the selection of the 'Flight State After'
3376 mode in pyro configuration.
3377 </p></li><li class="listitem"><p>
3378 Fix bug where erasing flights would reset the flight number
3379 to 2 on TeleMega and TeleMetrum v2.
3380 </p></li><li class="listitem"><p>
3381 Fix u-Blox GPS driver to mark course and speed data as being
3383 </p></li></ul></div><p>
3385 AltosUI New Features
3386 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3387 Add zooming and new content types (terrain and road maps) to
3388 map view. Change map storage format from PNG to Jpeg, which
3389 saves a huge amount of disk space. You will need to
3390 re-download all of your pre-loaded map images.
3391 </p></li><li class="listitem"><p>
3392 Add a distance measuring device to the maps view. Select
3393 this by using any button other than the left one, or by
3394 pressing shift or control on the keyboard while using the
3396 </p></li><li class="listitem"><p>
3397 Add new 'Ignitor' tab to the flight monitor display for
3398 TeleMega's extra ignitors.
3399 </p></li><li class="listitem"><p>
3400 Increase the width of data lines in the graphs to make them
3402 </p></li><li class="listitem"><p>
3403 Add additional ignitor firing marks and voltages to the
3404 graph so you can see when the ignitors fired, along with
3405 the ignitor voltages.
3406 </p></li><li class="listitem"><p>
3407 Add GPS course, ground speed and climb rate as optional
3409 </p></li></ul></div><p>
3412 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3413 When flashing new firmware, re-try opening the device as
3414 sometimes it takes a while for the underlying operating
3415 system to recognize that the device has rebooted in
3416 preparation for the flashing operation.
3417 </p></li><li class="listitem"><p>
3418 Hide Tilt Angle in ascent tab for devices that don't have a gyro.
3419 </p></li><li class="listitem"><p>
3420 Filter out speed and acceleration spikes caused by ejection
3421 charge firing when computing the maximum values. This
3422 provides a more accurate reading of those maximums.
3423 </p></li><li class="listitem"><p>
3424 Fix EasyMini voltage displays. Early EasyMini prototypes
3425 used a 3.0V regulator, and AltosUI still used that value as
3426 the basis of the computation. Production EasyMini boards
3427 have always shipped with a 3.3V regulator. Also, purple
3428 EasyMini boards sensed the battery voltage past the blocking
3429 diode, resulting in a drop of about 150mV from the true
3430 battery voltage. Compensate for that when displaying the
3432 </p></li><li class="listitem"><p>
3433 Display error message when trying to configure maximum
3434 flight log size while the flight computer still has flight
3436 </p></li><li class="listitem"><p>
3437 Handle TeleMetrum and TeleMini eeprom files generated with
3438 pre-1.0 firmware. Those ancient versions didn't report the
3439 log format, so just use the product name instead.
3440 </p></li></ul></div><p>
3443 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3444 New application designed for use with TeleGPS boards.
3445 </p></li><li class="listitem"><p>
3446 Shares code with AltosUI, mostly just trimmed down to focus
3447 on TeleGPS-related functions.
3448 </p></li></ul></div><p>
3450 Documentation changes
3451 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3452 Re-create the drill template images; they should print
3453 correctly from Firefox at least. Ship these as individual
3454 PDF files so they're easy to print.
3455 </p></li><li class="listitem"><p>
3456 Add a description of the 'Apogee Lockout' setting, which
3457 prevents the apogee charge from firing for a configurable
3458 amount of time after boost.
3459 </p></li></ul></div><p>
3460 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38030512"></a>Version 1.3.2</h2></div></div></div><p>
3461 Version 1.3.2 is a minor release. It includes small bug fixes for
3462 the TeleMega flight software and AltosUI ground station
3464 AltOS Firmware Changes
3465 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3466 On TeleMega, limit number of logged GPS status information
3467 to 12 satellites. That's all there is room for in the log
3469 </p></li><li class="listitem"><p>
3470 Improve APRS behavior. Remembers last known GPS position and
3471 keeps sending that if we lose GPS lock. Marks
3472 locked/unlocked by sending L/U in the APRS comment field
3473 along with the number of sats in view and voltages.
3474 </p></li></ul></div><p>
3477 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3478 If the TeleMega flight firmware reports that it has logged
3479 information about more than 12 satellites, don't believe it
3480 as the log only holds 12 satellite records.
3481 </p></li><li class="listitem"><p>
3482 Track the maximum height as computed from GPS altitude
3483 data and report that in the flight summary data.
3484 </p></li><li class="listitem"><p>
3485 Use letters (A, B, C, D) for alternate pyro channel names
3486 instead of numbers (0, 1, 2, 3) in the Fire Igniter dialog.
3487 </p></li></ul></div><p>
3488 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38032016"></a>Version 1.3.1</h2></div></div></div><p>
3489 Version 1.3.1 is a minor release. It improves support for TeleMega,
3490 TeleMetrum v2.0, TeleMini v2.0 and EasyMini.
3492 AltOS Firmware Changes
3493 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3494 Improve sensor boot code. If sensors fail to self-test, the
3495 device will still boot up and check for pad/idle modes. If
3496 in idle mode, the device will warn the user with a distinct
3497 beep, if in Pad mode, the unit will operate as best it
3498 can. Also, the Z-axis accelerometer now uses the factory
3499 calibration values instead of re-calibrating on the pad each
3500 time. This avoids accidental boost detect when moving the
3501 device around while in Pad mode.
3502 </p></li><li class="listitem"><p>
3503 Fix antenna-down mode accelerometer configuration. Antenna
3504 down mode wasn't working because the accelerometer
3505 calibration values were getting re-computed incorrectly in
3507 </p></li><li class="listitem"><p>
3508 Improved APRS mode. Now uses compressed position format for
3509 smaller data size, improved precision and to include
3510 altitude data as well as latitude and longitude. Also added
3511 battery and pyro voltage reports in the APRS comment field
3512 so you can confirm that the unit is ready for launch.
3513 </p></li></ul></div><p>
3516 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3517 Display additional TeleMega sensor values in real
3518 units. Make all of these values available for
3519 plotting. Display TeleMega orientation value in the Ascent
3521 </p></li><li class="listitem"><p>
3522 Support additional TeleMega pyro channels in the Fire
3523 Igniter dialog. This lets you do remote testing of all of
3524 the channels, rather than just Apogee and Main.
3525 </p></li><li class="listitem"><p>
3526 Limit data rate when downloading satellite images from
3527 Google to make sure we stay within their limits so that all
3528 of the map tiles download successfully.
3529 </p></li></ul></div><p>
3530 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38033520"></a>Version 1.3</h2></div></div></div><p>
3531 Version 1.3 is a major release. It adds support for TeleMega,
3532 TeleMetrum v2.0, TeleMini v2.0 and EasyMini.
3534 AltOS Firmware Changes
3535 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3536 Add STM32L processor support. This includes enhancements to
3537 the scheduler to support products with many threads.
3538 </p></li><li class="listitem"><p>
3539 Add NXP LPC11U14 processor support.
3540 </p></li><li class="listitem"><p>
3541 Support additional pyro channels. These are configurable
3542 through the UI to handle air starts, staging, additional
3543 recovery events and external devices such as cameras.
3544 </p></li><li class="listitem"><p>
3545 Add 3-axis gyro support for orientation tracking. This
3546 integrates the gyros to compute the angle from vertical during
3547 flight, allowing the additional pyro events to be controlled
3549 </p></li><li class="listitem"><p>
3550 Many more device drivers, including u-Blox Max 7Q GPS,
3551 Freescale MMA6555 digital single-axis accelerometer,
3552 Invensense MPU6000 3-axis accelerometer + 3 axis gyro,
3553 Honeywell HMC5883 3-axis magnetic sensor and the TI CC1120 and
3554 CC115L digital FM transceivers
3555 </p></li></ul></div><p>
3558 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3559 Support TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini telemetry and log formats.
3560 </p></li><li class="listitem"><p>
3561 Use preferred units for main deployment height configuration,
3562 instead of always doing configuration in meters.
3563 </p></li></ul></div><p>
3565 MicroPeak UI changes
3566 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3567 Add 'Download' button to menu bar.
3568 </p></li><li class="listitem"><p>
3569 Save the last log directory and offer that as the default for new downloads
3570 </p></li></ul></div><p>
3571 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38035024"></a>Version 1.2.1</h2></div></div></div><p>
3572 Version 1.2.1 is a minor release. It adds support for TeleBT and
3573 the AltosDroid application, provides several new features in
3574 AltosUI and fixes some bugs in the AltOS firmware.
3576 AltOS Firmware Changes
3577 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3578 Add support for TeleBT
3579 </p></li><li class="listitem"><p>
3580 In TeleMini recovery mode (when booted with the outer two
3581 debug pins connected together), the radio parameters are also
3582 set back to defaults (434.550MHz, N0CALL, factory radio cal).
3583 </p></li><li class="listitem"><p>
3584 Add support for reflashing the SkyTraq GPS chips. This
3585 requires special host-side code which currently only exists
3587 </p></li><li class="listitem"><p>
3588 Correct Kalman filter model error covariance matrix. The
3589 values used previously assumed continuous measurements instead
3590 of discrete measurements.
3591 </p></li><li class="listitem"><p>
3592 Fix some bugs in the USB driver for TeleMetrum and TeleDongle
3593 that affected Windows users.
3594 </p></li><li class="listitem"><p>
3595 Adjusted the automatic gain control parameters that affect
3596 receive performance for TeleDongle. Field tests indicate that this
3597 may improve receive performance somewhat.
3598 </p></li></ul></div><p>
3601 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3602 Handle missing GPS lock in 'Descent' tab. Previously, if the
3603 GPS position of the pad was unknown, an exception would be
3604 raised, breaking the Descent tab contents.
3605 </p></li><li class="listitem"><p>
3606 Improve the graph, adding tool-tips to show values near the
3607 cursor and making the displayed set of values configurable,
3608 adding all of the flight data as options while leaving the
3609 default settings alone so that the graph starts by showing
3610 height, speed and acceleration.
3611 </p></li><li class="listitem"><p>
3612 Make the initial position of the AltosUI top level window
3613 configurable. Along with this change, the other windows will
3614 pop up at 'sensible' places now, instead of on top of one
3616 </p></li><li class="listitem"><p>
3617 Add callsign to Monitor idle window and connecting
3618 dialogs. This makes it clear which callsign is being used so
3619 that the operator will be aware that it must match the flight
3620 computer value or no communication will work.
3621 </p></li><li class="listitem"><p>
3622 When downloading flight data, display the block number so that
3623 the user has some sense of progress. Unfortunately, we don't
3624 know how many blocks will need to be downloaded, but at least
3625 it isn't just sitting there doing nothing for a long time.
3626 </p></li><li class="listitem"><p>
3627 Add GPS data and a map to the graph window. This lets you see
3628 a complete summary of the flight without needing to 'replay'
3630 </p></li></ul></div><p>
3631 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38036528"></a>Version 1.2</h2></div></div></div><p>
3632 Version 1.2 is a major release. It adds support for MicroPeak and
3633 the MicroPeak USB adapter.
3635 AltOS Firmware Changes
3636 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3637 Add MicroPeak support. This includes support for the ATtiny85
3638 processor and adaptations to the core code to allow for
3639 devices too small to run the multi-tasking scheduler.
3640 </p></li></ul></div><p>
3642 MicroPeak UI changes
3643 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3644 Added this new application
3645 </p></li></ul></div><p>
3647 Distribution Changes
3648 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3649 Distribute Mac OS X packages in disk image ('.dmg') format to
3650 greatly simplify installation.
3651 </p></li><li class="listitem"><p>
3652 Provide version numbers for the shared Java libraries to
3653 ensure that upgrades work properly, and to allow for multiple
3654 Altus Metrum software packages to be installed in the same
3655 directory at the same time.
3656 </p></li></ul></div><p>
3657 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38038032"></a>Version 1.1.1</h2></div></div></div><p>
3658 Version 1.1.1 is a bug-fix release. It fixes a couple of bugs in
3659 AltosUI and one firmware bug that affects TeleMetrum version 1.0
3660 boards. Thanks to Bob Brown for help diagnosing the Google Earth
3661 file export issue, and for suggesting the addition of the Ground
3662 Distance value in the Descent tab.
3664 AltOS Firmware Changes
3665 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3666 TeleMetrum v1.0 boards use the AT45DB081D flash memory part to
3667 store flight data, which is different from later TeleMetrum
3668 boards. The AltOS v1.1 driver for this chip couldn't erase
3669 memory, leaving it impossible to delete flight data or update
3670 configuration values. This bug doesn't affect newer TeleMetrum
3671 boards, and it doesn't affect the safety of rockets flying
3672 version 1.1 firmware.
3673 </p></li></ul></div><p>
3676 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3677 Creating a Google Earth file (KML) from on-board flight data
3678 (EEPROM) would generate an empty file. The code responsible
3679 for reading the EEPROM file wasn't ever setting the GPS valid
3680 bits, and so the KML export code thought there was no GPS data
3682 </p></li><li class="listitem"><p>
3683 The “Landed” tab was displaying all values in metric units,
3684 even when AltosUI was configured to display imperial
3685 units. Somehow I just missed this tab when doing the units stuff.
3686 </p></li><li class="listitem"><p>
3687 The “Descent” tab displays the range to the rocket, which is a
3688 combination of the over-the-ground distance to the rockets
3689 current latitude/longitude and the height of the rocket. As
3690 such, it's useful for knowing how far away the rocket is, but
3691 difficult to use when estimating where the rocket might
3692 eventually land. A new “Ground Distance” field has been added
3693 which displays the distance to a spot right underneath the
3695 </p></li><li class="listitem"><p>
3696 Sensor data wasn't being displayed for TeleMini flight
3697 computers in Monitor Idle mode, including things like battery
3698 voltage. The code that picked which kinds of data to fetch
3699 from the flight computer was missing a check for TeleMini when
3700 deciding whether to fetch the analog sensor data.
3701 </p></li></ul></div><p>
3702 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38039536"></a>Version 1.1</h2></div></div></div><p>
3703 Version 1.1 is a minor release. It provides a few new features in AltosUI
3704 and the AltOS firmware and fixes bugs.
3706 AltOS Firmware Changes
3707 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3708 Add apogee-lockout value. Overrides the apogee detection logic to
3709 prevent incorrect apogee charge firing.
3710 </p></li><li class="listitem"><p>
3711 Fix a bug where the data reported in telemetry packets was
3713 </p></li><li class="listitem"><p>
3714 Force the radio frequency to 434.550MHz when the debug clock
3715 pin is connected to ground at boot time. This provides a way
3716 to talk to a TeleMini which is configured to some unknown frequency.
3717 </p></li><li class="listitem"><p>
3718 Provide RSSI values for Monitor Idle mode. This makes it easy to check radio
3719 range without needing to go to flight mode.
3720 </p></li><li class="listitem"><p>
3721 Fix a bug which caused the old received telemetry packets to
3722 be retransmitted over the USB link when the radio was turned
3724 </p></li></ul></div><p>
3727 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3728 Fix a bug that caused GPS ready to happen too quickly. The
3729 software was using every telemetry packet to signal new GPS
3730 data, which caused GPS ready to be signalled after 10 packets
3731 instead of 10 GPS updates.
3732 </p></li><li class="listitem"><p>
3733 Fix Google Earth data export to work with recent versions. The
3734 google earth file loading code got a lot pickier, requiring
3735 some minor white space changes in the export code.
3736 </p></li><li class="listitem"><p>
3737 Make the look-n-feel configurable, providing a choice from
3738 the available options.
3739 </p></li><li class="listitem"><p>
3740 Add an 'Age' element to mark how long since a telemetry packet
3741 has been received. Useful to quickly gauge whether
3742 communications with the rocket are still active.
3743 </p></li><li class="listitem"><p>
3744 Add 'Configure Ground Station' dialog to set the radio
3745 frequency used by a particular TeleDongle without having to go
3746 through the flight monitor UI.
3747 </p></li><li class="listitem"><p>
3748 Add configuration for the new apogee-lockout value. A menu provides a list of
3749 reasonable values, or the value can be set by hand.
3750 </p></li><li class="listitem"><p>
3751 Changed how flight data are downloaded. Now there's an initial
3752 dialog asking which flights to download, and after that
3753 finishes, a second dialog comes up asking which flights to delete.
3754 </p></li><li class="listitem"><p>
3755 Re-compute time spent in each state for the flight graph; this
3756 figures out the actual boost and landing times instead of
3757 using the conservative values provide by the flight
3758 electronics. This improves the accuracy of the boost
3759 acceleration and main descent rate computations.
3760 </p></li><li class="listitem"><p>
3761 Make AltosUI run on Mac OS Lion. The default Java heap space
3762 was dramatically reduced for this release causing much of the
3763 UI to fail randomly. This most often affected the satellite
3764 mapping download and displays.
3765 </p></li><li class="listitem"><p>
3766 Change how data are displayed in the 'table' tab of the flight
3767 monitoring window. This eliminates entries duplicated from the
3768 header and adds both current altitude and pad altitude, which
3769 are useful in 'Monitor Idle' mode.
3770 </p></li><li class="listitem"><p>
3771 Add Imperial units mode to present data in feet instead of
3773 </p></li></ul></div><p>
3774 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38041040"></a>Version 1.0.1</h2></div></div></div><p>
3775 Version 1.0.1 is a major release, adding support for the TeleMini
3776 device and lots of new AltosUI features
3778 AltOS Firmware Changes
3779 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3780 Add TeleMini v1.0 support. Firmware images for TeleMini are
3781 included in AltOS releases.
3782 </p></li><li class="listitem"><p>
3783 Change telemetry to be encoded in multiple 32-byte packets. This
3784 enables support for TeleMini and other devices without requiring
3785 further updates to the TeleDongle firmware.
3786 </p></li><li class="listitem"><p>
3787 Support operation of TeleMetrum with the antenna pointing
3788 aft. Previous firmware versions required the antenna to be
3789 pointing upwards, now there is a configuration option allowing
3790 the antenna to point aft, to aid installation in some airframes.
3791 </p></li><li class="listitem"><p>
3792 Ability to disable telemetry. For airframes where an antenna
3793 just isn't possible, or where radio transmissions might cause
3794 trouble with other electronics, there's a configuration option
3795 to disable all telemetry. Note that the board will still
3796 enable the radio link in idle mode.
3797 </p></li><li class="listitem"><p>
3798 Arbitrary frequency selection. The radios in Altus Metrum
3799 devices can be programmed to a wide range of frequencies, so
3800 instead of limiting devices to 10 pre-selected 'channels', the
3801 new firmware allows the user to choose any frequency in the
3802 70cm band. Note that the RF matching circuit on the boards is
3803 tuned for around 435MHz, so frequencies far from that may
3804 reduce the available range.
3805 </p></li><li class="listitem"><p>
3806 Kalman-filter based flight-tracking. The model based sensor
3807 fusion approach of a Kalman filter means that AltOS now
3808 computes apogee much more accurately than before, generally
3809 within a fraction of a second. In addition, this approach
3810 allows the baro-only TeleMini device to correctly identify
3811 Mach transitions, avoiding the error-prone selection of a Mach
3813 </p></li></ul></div><p>
3816 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3817 Wait for altimeter when using packet mode. Instead of quicly
3818 timing out when trying to initialize a packet mode
3819 configuration connection, AltosUI now waits indefinitely for
3820 the remote device to appear, providing a cancel button should
3821 the user get bored. This is necessary as the TeleMini can only
3822 be placed in "Idle" mode if AltosUI is polling it.
3823 </p></li><li class="listitem"><p>
3824 Add main/apogee voltage graphs to the data plot. This provides
3825 a visual indication if the igniters fail before being fired.
3826 </p></li><li class="listitem"><p>
3827 Scan for altimeter devices by watching the defined telemetry
3828 frequencies. This avoids the problem of remembering what
3829 frequency a device was configured to use, which is especially
3830 important with TeleMini which does not include a USB connection.
3831 </p></li><li class="listitem"><p>
3832 Monitor altimeter state in "Idle" mode. This provides much of
3833 the information presented in the "Pad" dialog from the Monitor
3834 Flight command, monitoring the igniters, battery and GPS
3835 status withing requiring the flight computer to be armed and
3837 </p></li><li class="listitem"><p>
3838 Pre-load map images from home. For those launch sites which
3839 don't provide free Wi-Fi, this allows you to download the
3840 necessary satellite images given the location of the launch
3841 site. A list of known launch sites is maintained at
3842 altusmetrum.org which AltosUI downloads to populate a menu; if
3843 you've got a launch site not on that list, please send the
3844 name of it, latitude and longitude along with a link to the
3845 web site of the controlling club to the altusmetrum mailing list.
3846 </p></li><li class="listitem"><p>
3847 Flight statistics are now displayed in the Graph data
3848 window. These include max height/speed/accel, average descent
3849 rates and a few other bits of information. The Graph Data
3850 window can now be reached from the 'Landed' tab in the Monitor
3851 Flight window so you can immediately see the results of a
3853 </p></li></ul></div><p>
3854 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38042544"></a>Version 0.9.2</h2></div></div></div><p>
3855 Version 0.9.2 is an AltosUI bug-fix release, with no firmware changes.
3856 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3857 Fix plotting problems due to missing file in the Mac OS install image.
3858 </p></li><li class="listitem"><p>
3859 Always read whole eeprom blocks, mark empty records invalid, display parsing errors to user.
3860 </p></li><li class="listitem"><p>
3861 Add software version to Configure AltosUI dialog
3862 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38044048"></a>Version 0.9</h2></div></div></div><p>
3863 Version 0.9 adds a few new firmware features and accompanying
3864 AltosUI changes, along with new hardware support.
3865 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3866 Support for TeleMetrum v1.1 hardware. Sources for the flash
3867 memory part used in v1.0 dried up, so v1.1 uses a different part
3868 which required a new driver and support for explicit flight log
3870 </p></li><li class="listitem"><p>
3871 Multiple flight log support. This stores more than one flight
3872 log in the on-board flash memory. It also requires the user to
3873 explicitly erase flights so that you won't lose flight logs just
3874 because you fly the same board twice in one day.
3875 </p></li><li class="listitem"><p>
3876 Telemetry support for devices with serial number >=
3877 256. Previous versions used a telemetry packet format that
3878 provided only 8 bits for the device serial number. This change
3879 requires that both ends of the telemetry link be running the 0.9
3880 firmware or they will not communicate.
3881 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38045552"></a>Version 0.8</h2></div></div></div><p>
3882 Version 0.8 offers a major upgrade in the AltosUI
3883 interface. Significant new features include:
3884 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3885 Post-flight graphing tool. This lets you explore the behaviour
3886 of your rocket after flight with a scroll-able and zoom-able
3887 chart showing the altitude, speed and acceleration of the
3888 airframe along with events recorded by the flight computer. You
3889 can export graphs to PNG files, or print them directly.
3890 </p></li><li class="listitem"><p>
3891 Real-time moving map which overlays the in-progress flight on
3892 satellite imagery fetched from Google Maps. This lets you see in
3893 pictures where your rocket has landed, allowing you to plan
3894 recovery activities more accurately.
3895 </p></li><li class="listitem"><p>
3896 Wireless recovery system testing. Prep your rocket for flight
3897 and test fire the deployment charges to make sure things work as
3898 expected. All without threading wires through holes in your
3900 </p></li><li class="listitem"><p>
3901 Optimized flight status displays. Each flight state now has it's
3902 own custom 'tab' in the flight monitoring window so you can
3903 focus on the most important details. Pre-flight, the system
3904 shows a set of red/green status indicators for battery voltage,
3905 apogee/main igniter continutity and GPS reception. Wait until
3906 they're all green and your rocket is ready for flight. There are
3907 also tabs for ascent, descent and landing along with the
3908 original tabular view of the data.
3909 </p></li><li class="listitem"><p>
3910 Monitor multiple flights simultaneously. If you have more than
3911 one TeleDongle, you can monitor a flight with each one on the
3913 </p></li><li class="listitem"><p>
3914 Automatic flight monitoring at startup. Plug TeleDongle into the
3915 machine before starting AltosUI and it will automatically
3916 connect to it and prepare to monitor a flight.
3917 </p></li><li class="listitem"><p>
3918 Exports Google Earth flight tracks. Using the Keyhole Markup
3919 Language (.kml) file format, this provides a 3D view of your
3920 rocket flight through the Google Earth program.
3921 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp38047056"></a>Version 0.7.1</h2></div></div></div><p>
3922 Version 0.7.1 is the first release containing our new cross-platform Java-based user interface. AltosUI can:
3923 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3924 Receive and log telemetry from a connected TeleDongle
3925 device. All data received is saved to log files named with the
3926 current date and the connected rocket serial and flight
3927 numbers. There is no mode in which telemetry data will not be
3929 </p></li><li class="listitem"><p>
3930 Download logged data from TeleMetrum devices, either through a
3931 direct USB connection or over the air through a TeleDongle
3933 </p></li><li class="listitem"><p>
3934 Configure a TeleMetrum device, setting the radio channel,
3935 callsign, apogee delay and main deploy height. This can be done
3936 through either a USB connection or over a radio link via a
3938 </p></li><li class="listitem"><p>
3939 Replay a flight in real-time. This takes a saved telemetry log
3940 or eeprom download and replays it through the user interface so
3941 you can relive your favorite rocket flights.
3942 </p></li><li class="listitem"><p>
3943 Reprogram Altus Metrum devices. Using an Altus Metrum device
3944 connected via USB, another Altus Metrum device can be
3945 reprogrammed using the supplied programming cable between the
3947 </p></li><li class="listitem"><p>
3948 Export Flight data to a comma-separated-values file. This takes
3949 either telemetry or on-board flight data and generates data
3950 suitable for use in external applications. All data is exported
3951 using standard units so that no device-specific knowledge is
3952 needed to handle the data.
3953 </p></li><li class="listitem"><p>
3954 Speak to you during the flight. Instead of spending the flight
3955 hunched over your laptop looking at the screen, enjoy the view
3956 while the computer tells you what’s going on up there. During
3957 ascent, you hear the current flight state and altitude
3958 information. During descent, you get azimuth, elevation and
3959 range information to try and help you find your rocket in the
3960 air. Once on the ground, the direction and distance are
3962 </p></li></ul></div></div></div></div></body></html>