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="idp16901520"></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 © 2014 Bdale Garbee and Keith Packard</p></div><div><div class="legalnotice"><a name="idp43234368"></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 1.5</td><td align="left">6 September 2014</td></tr><tr><td align="left" colspan="2">
8 Major release adding EasyMega support.
9 </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">
10 Minor release fixing some installation bugs.
11 </td></tr><tr><td align="left">Revision 1.4</td><td align="left">15 June 2014</td></tr><tr><td align="left" colspan="2">
12 Major release adding TeleGPS support.
13 </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">
14 Bug fixes for TeleMega and AltosUI.
15 </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">
16 Bug fixes for TeleMega and TeleMetrum v2.0 along with a few
17 small UI improvements.
18 </td></tr><tr><td align="left">Revision 1.3</td><td align="left">12 November 2013</td></tr><tr><td align="left" colspan="2">
19 Updated for software version 1.3. Version 1.3 adds support
20 for TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini
21 and fixes bugs in AltosUI and the AltOS firmware.
22 </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">
23 Updated for software version 1.2. Version 1.2 adds support
24 for TeleBT and AltosDroid. It also adds a few minor features
25 and fixes bugs in AltosUI and the AltOS firmware.
26 </td></tr><tr><td align="left">Revision 1.2</td><td align="left">18 April 2013</td></tr><tr><td align="left" colspan="2">
27 Updated for software version 1.2. Version 1.2 adds support
28 for MicroPeak and the MicroPeak USB interface.
29 </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">
30 Updated for software version 1.1.1 Version 1.1.1 fixes a few
31 bugs found in version 1.1.
32 </td></tr><tr><td align="left">Revision 1.1</td><td align="left">13 September 2012</td></tr><tr><td align="left" colspan="2">
33 Updated for software version 1.1. Version 1.1 has new
34 features but is otherwise compatible with version 1.0.
35 </td></tr><tr><td align="left">Revision 1.0</td><td align="left">24 August 2011</td></tr><tr><td align="left" colspan="2">
36 Updated for software version 1.0. Note that 1.0 represents a
37 telemetry format change, meaning both ends of a link
38 (TeleMetrum/TeleMini and TeleDongle) must be updated or
39 communications will fail.
40 </td></tr><tr><td align="left">Revision 0.9</td><td align="left">18 January 2011</td></tr><tr><td align="left" colspan="2">
41 Updated for software version 0.9. Note that 0.9 represents a
42 telemetry format change, meaning both ends of a link (TeleMetrum and
43 TeleDongle) must be updated or communications will fail.
44 </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="idp43407920"></a>Acknowledgments</h1></div></div></div><p>
45 Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing “The
46 Mere-Mortals Quick Start/Usage Guide to the Altus Metrum Starter
47 Kit” which formed the basis of the original Getting Started chapter
48 in this manual. Bob was one of our first customers for a production
49 TeleMetrum, and his continued enthusiasm and contributions
50 are immensely gratifying and highly appreciated!
52 And thanks to Anthony (AJ) Towns for major contributions including
53 the AltosUI graphing and site map code and associated documentation.
54 Free software means that our customers and friends can become our
55 collaborators, and we certainly appreciate this level of
58 Have fun using these products, and we hope to meet all of you
59 out on the rocket flight line somewhere.
60 </p><div class="literallayout"><p><br>
61 Bdale Garbee, KB0G<br>
62 NAR #87103, TRA #12201<br>
64 Keith Packard, KD7SQG<br>
65 NAR #88757, TRA #12200<br>
67 </p></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="chapter"><a href="#idp43412128">1. Introduction and Overview</a></span></dt><dt><span class="chapter"><a href="#idp43239632">2. Getting Started</a></span></dt><dt><span class="chapter"><a href="#idp43249600">3. Handling Precautions</a></span></dt><dt><span class="chapter"><a href="#idp43255088">4. Altus Metrum Hardware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp43255760">1. General Usage Instructions</a></span></dt><dd><dl><dt><span class="section"><a href="#idp43257728">1.1. Hooking Up Lithium Polymer Batteries</a></span></dt><dt><span class="section"><a href="#idp43260736">1.2. Hooking Up Pyro Charges</a></span></dt><dt><span class="section"><a href="#idp43262816">1.3. Hooking Up a Power Switch</a></span></dt><dt><span class="section"><a href="#idp43266032">1.4. Using a Separate Pyro Battery</a></span></dt><dt><span class="section"><a href="#idp43268544">1.5. Using a Different Kind of Battery</a></span></dt></dl></dd><dt><span class="section"><a href="#idp43270288">2. Specifications</a></span></dt><dt><span class="section"><a href="#idp48828432">3. TeleMetrum</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48831824">3.1. TeleMetrum Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp48861136">3.2. Using a Separate Pyro Battery with TeleMetrum</a></span></dt><dt><span class="section"><a href="#idp48864384">3.3. Using an Active Switch with TeleMetrum</a></span></dt></dl></dd><dt><span class="section"><a href="#idp48866512">4. TeleMini v1.0</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48871408">4.1. TeleMini v1.0 Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp48890752">4.2. Using a Separate Pyro Battery with TeleMini v1.0</a></span></dt><dt><span class="section"><a href="#idp48894128">4.3. Using an Active Switch with TeleMini v1.0</a></span></dt></dl></dd><dt><span class="section"><a href="#idp48896336">5. TeleMini v2.0</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48900352">5.1. TeleMini v2.0 Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp48922736">5.2. Using a Separate Pyro Battery with TeleMini v2.0</a></span></dt><dt><span class="section"><a href="#idp48925936">5.3. Using an Active Switch with TeleMini v2.0</a></span></dt></dl></dd><dt><span class="section"><a href="#idp48928032">6. EasyMini</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48931888">6.1. EasyMini Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp48954272">6.2. Using a Separate Pyro Battery with EasyMini</a></span></dt><dt><span class="section"><a href="#idp48957456">6.3. Using an Active Switch with EasyMini</a></span></dt></dl></dd><dt><span class="section"><a href="#idp48959552">7. TeleMega</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48963520">7.1. TeleMega Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp49001024">7.2. Using a Separate Pyro Battery with TeleMega</a></span></dt><dt><span class="section"><a href="#idp49002624">7.3. Using Only One Battery With TeleMega</a></span></dt><dt><span class="section"><a href="#idp49004544">7.4. Using an Active Switch with TeleMega</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49006592">8. EasyMega</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49010560">8.1. EasyMega Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp49048064">8.2. Using a Separate Pyro Battery with EasyMega</a></span></dt><dt><span class="section"><a href="#idp49049664">8.3. Using Only One Battery With EasyMega</a></span></dt><dt><span class="section"><a href="#idp49051584">8.4. Using an Active Switch with EasyMega</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49053632">9. Flight Data Recording</a></span></dt><dt><span class="section"><a href="#idp49084400">10. Installation</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp49091680">5. System Operation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49092320">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp49160720">2. GPS </a></span></dt><dt><span class="section"><a href="#idp49163504">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp49174800">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp49177552">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp49181552">6. APRS</a></span></dt><dt><span class="section"><a href="#idp49205872">7. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49207792">7.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp49209840">7.2. Callsign</a></span></dt><dt><span class="section"><a href="#idp49211376">7.3. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp49212672">7.4. Telemetry baud rate</a></span></dt><dt><span class="section"><a href="#idp49214240">7.5. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp49215712">7.6. APRS SSID</a></span></dt><dt><span class="section"><a href="#idp49217056">7.7. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp49219648">7.8. Apogee Lockout</a></span></dt><dt><span class="section"><a href="#idp49221376">7.9. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp49223072">7.10. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp49225216">7.11. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp49227328">7.12. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp49229568">7.13. Configurable Pyro Channels</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="#idp49252176">6. AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49255792">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49268512">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp49284800">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp49290256">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp49297120">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp49303552">1.5. Table</a></span></dt><dt><span class="section"><a href="#idp49307136">1.6. Site Map</a></span></dt><dt><span class="section"><a href="#idp49313856">1.7. Ignitor</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49317632">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp49321584">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp49323616">4. Graph Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49326000">4.1. Flight Graph</a></span></dt><dt><span class="section"><a href="#idp49330448">4.2. Configure Graph</a></span></dt><dt><span class="section"><a href="#idp49334112">4.3. Flight Statistics</a></span></dt><dt><span class="section"><a href="#idp49337632">4.4. Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49341488">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49343056">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp49345408">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49346896">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49359200">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp49360768">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp49362384">6.3. Apogee Lockoug</a></span></dt><dt><span class="section"><a href="#idp49364112">6.4. Frequency</a></span></dt><dt><span class="section"><a href="#idp49365616">6.5. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp49367264">6.6. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp49368560">6.7. Telemetry baud rate</a></span></dt><dt><span class="section"><a href="#idp49370128">6.8. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp49371696">6.9. APRS SSID</a></span></dt><dt><span class="section"><a href="#idp49373024">6.10. Callsign</a></span></dt><dt><span class="section"><a href="#idp49374336">6.11. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp49375776">6.12. Ignitor Firing Mode</a></span></dt><dt><span class="section"><a href="#idp49382688">6.13. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp49387920">6.14. Beeper Frequency</a></span></dt><dt><span class="section"><a href="#idp49389376">6.15. Configure Pyro Channels</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49395760">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49399264">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp49404288">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp49406288">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp49408528">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp49410032">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp49411312">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp49412816">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49414448">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49425568">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp49427136">8.2. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp49428656">8.3. Telemetry Rate</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49430128">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp49431776">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp49437408">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp49441632">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp49455600">13. Monitor Idle</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp49457696">7. AltosDroid</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49460080">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp49462016">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp49464016">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp49465472">4. AltosDroid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49466784">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49480336">5. Downloading Flight Logs</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp49482000">8. Using Altus Metrum Products</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49482640">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp49484544">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp49487072">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp49500464">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp49503008">5. Future Plans</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp49506848">9. Altimeter Installation Recommendations</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49508304">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp49513136">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp49518704">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp49523488">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp49531056">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp49533856">6. Ground Testing</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp49537024">10. Updating Device Firmware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49541072">1.
68 Updating TeleMega, TeleMetrum v2, EasyMega or EasyMini Firmware
69 </a></span></dt><dd><dl><dt><span class="section"><a href="#idp49550144">1.1. Recovering From Self-Flashing Failure</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49568720">2. Pair Programming</a></span></dt><dt><span class="section"><a href="#idp49570160">3. Updating TeleMetrum v1.x Firmware</a></span></dt><dt><span class="section"><a href="#idp49583360">4. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp49596912">5. Updating TeleDongle Firmware</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp49613536">11. Hardware Specifications</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49614176">1.
70 TeleMega Specifications
71 </a></span></dt><dt><span class="section"><a href="#idp49625648">2.
72 EasyMega Specifications
73 </a></span></dt><dt><span class="section"><a href="#idp49635392">3.
74 TeleMetrum v2 Specifications
75 </a></span></dt><dt><span class="section"><a href="#idp49645952">4. TeleMetrum v1 Specifications</a></span></dt><dt><span class="section"><a href="#idp49656512">5.
76 TeleMini v2.0 Specifications
77 </a></span></dt><dt><span class="section"><a href="#idp49665344">6.
78 TeleMini v1.0 Specifications
79 </a></span></dt><dt><span class="section"><a href="#idp49674144">7.
80 EasyMini Specifications
81 </a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp49682256">12. FAQ</a></span></dt><dt><span class="appendix"><a href="#idp49691104">A. Notes for Older Software</a></span></dt><dt><span class="appendix"><a href="#idp49713504">B. Drill Templates</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49714672">1. TeleMega template</a></span></dt><dt><span class="section"><a href="#idp49731360">2. EasyMega template</a></span></dt><dt><span class="section"><a href="#idp49735744">3. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp49740128">4. TeleMini v2/EasyMini template</a></span></dt><dt><span class="section"><a href="#idp49744528">5. TeleMini v1 template</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp49749040">C. Calibration</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49750592">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp49755136">2. TeleMetrum, TeleMega and EasyMega Accelerometers</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp49760816">D. 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="#idp48750064">Altus Metrum Electronics</a></dt><dt>4.2. <a href="#idp48804240">Altus Metrum Boards</a></dt><dt>4.3. <a href="#idp43191248">TeleMetrum Screw Terminals</a></dt><dt>4.4. <a href="#idp48872848">TeleMini v1.0 Connections</a></dt><dt>4.5. <a href="#idp48901760">TeleMini v2.0 Connections</a></dt><dt>4.6. <a href="#idp48933296">EasyMini Connections</a></dt><dt>4.7. <a href="#idp48964688">TeleMega Screw Terminals</a></dt><dt>4.8. <a href="#idp49011728">EasyMega Screw Terminals</a></dt><dt>4.9. <a href="#idp49055040">Data Storage on Altus Metrum altimeters</a></dt><dt>5.1. <a href="#idp49097680">AltOS Modes</a></dt><dt>5.2. <a href="#idp49134768">Pad/Idle Indications</a></dt><dt>5.3. <a href="#idp49185360">Altus Metrum APRS Comments</a></dt></dl></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp43412128"></a>Chapter 1. Introduction and Overview</h1></div></div></div><p>
82 Welcome to the Altus Metrum community! Our circuits and software reflect
83 our passion for both hobby rocketry and Free Software. We hope their
84 capabilities and performance will delight you in every way, but by
85 releasing all of our hardware and software designs under open licenses,
86 we also hope to empower you to take as active a role in our collective
89 The first device created for our community was TeleMetrum, a dual
90 deploy altimeter with fully integrated GPS and radio telemetry
91 as standard features, and a “companion interface” that will
92 support optional capabilities in the future. The latest version
93 of TeleMetrum, v2.0, has all of the same features but with
94 improved sensors and radio to offer increased performance.
96 Our second device was TeleMini, a dual deploy altimeter with
97 radio telemetry and radio direction finding. The first version
98 of this device was only 13mm by 38mm (½ inch by 1½ inches) and
99 could fit easily in an 18mm air-frame. The latest version, v2.0,
100 includes a beeper, USB data download and extended on-board
101 flight logging, along with an improved barometric sensor.
103 TeleMega is our most sophisticated device, including six pyro
104 channels (four of which are fully programmable), integrated GPS,
105 integrated gyroscopes for staging/air-start inhibit and high
106 performance telemetry.
108 EasyMini is a dual-deploy altimeter with logging and built-in
111 EasyMega is essentially a TeleMega board with the GPS receiver
112 and telemetry transmitter removed. It offers the same 6 pyro
113 channels and integrated gyroscopes for staging/air-start inhibit.
115 TeleDongle was our first ground station, providing a USB to RF
116 interfaces for communicating with the altimeters. Combined with
117 your choice of antenna and notebook computer, TeleDongle and our
118 associated user interface software form a complete ground
119 station capable of logging and displaying in-flight telemetry,
120 aiding rocket recovery, then processing and archiving flight
121 data for analysis and review.
123 For a slightly more portable ground station experience that also
124 provides direct rocket recovery support, TeleBT offers flight
125 monitoring and data logging using a Bluetooth™ connection between
126 the receiver and an Android device that has the AltosDroid
127 application installed from the Google Play store.
129 More products will be added to the Altus Metrum family over time, and
130 we currently envision that this will be a single, comprehensive manual
131 for the entire product family.
132 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp43239632"></a>Chapter 2. Getting Started</h1></div></div></div><p>
133 The first thing to do after you check the inventory of parts in your
134 “starter kit” is to charge the battery.
136 For TeleMetrum, TeleMega and EasyMega, the battery can be charged by plugging it into the
137 corresponding socket of the device and then using the USB
138 cable to plug the flight computer into your computer's USB socket. The
139 on-board circuitry will charge the battery whenever it is plugged
140 in, because the on-off switch does NOT control the
143 On TeleMetrum v1 boards, when the GPS chip is initially
144 searching for satellites, TeleMetrum will consume more current
145 than it pulls from the USB port, so the battery must be
146 attached in order to get satellite lock. Once GPS is locked,
147 the current consumption goes back down enough to enable charging
148 while running. So it's a good idea to fully charge the battery
149 as your first item of business so there is no issue getting and
150 maintaining satellite lock. The yellow charge indicator led
151 will go out when the battery is nearly full and the charger goes
152 to trickle charge. It can take several hours to fully recharge a
153 deeply discharged battery.
155 TeleMetrum v2.0, TeleMega and EasyMega use a higher power battery charger,
156 allowing them to charge the battery while running the board at
157 maximum power. When the battery is charging, or when the board
158 is consuming a lot of power, the red LED will be lit. When the
159 battery is fully charged, the green LED will be lit. When the
160 battery is damaged or missing, both LEDs will be lit, which
163 The Lithium Polymer TeleMini and EasyMini battery can be charged by
164 disconnecting it from the board and plugging it into a
165 standalone battery charger such as the LipoCharger product
166 included in TeleMini Starter Kits, and connecting that via a USB
167 cable to a laptop or other USB power source.
169 You can also choose to use another battery with TeleMini v2.0
170 and EasyMini, anything supplying between 4 and 12 volts should
171 work fine (like a standard 9V battery), but if you are planning
172 to fire pyro charges, ground testing is required to verify that
173 the battery supplies enough current to fire your chosen e-matches.
175 The other active device in the starter kit is the TeleDongle USB to
176 RF interface. If you plug it in to your Mac or Linux computer it should
177 “just work”, showing up as a serial port device. Windows systems need
178 driver information that is part of the AltOS download to know that the
179 existing USB modem driver will work. We therefore recommend installing
180 our software before plugging in TeleDongle if you are using a Windows
181 computer. If you are using an older version of Linux and are having
182 problems, try moving to a fresher kernel (2.6.33 or newer).
184 Next you should obtain and install the AltOS software. The AltOS
185 distribution includes the AltosUI ground station program, current
187 images for all of the hardware, and a number of standalone
188 utilities that are rarely needed. Pre-built binary packages are
189 available for Linux, Microsoft Windows, and recent MacOSX
190 versions. Full source code and build instructions are also
191 available. The latest version may always be downloaded from
192 <a class="ulink" href="http://altusmetrum.org/AltOS" target="_top">http://altusmetrum.org/AltOS</a>.
194 If you're using a TeleBT instead of the TeleDongle, you'll want to
195 install the AltosDroid application from the Google Play store on an
196 Android device. You don't need a data plan to use AltosDroid, but
197 without network access, the Map view will be less useful as it
198 won't contain any map data. You can also use TeleBT connected
199 over USB with your laptop computer; it acts exactly like a
200 TeleDongle. Anywhere this manual talks about TeleDongle, you can
201 also read that as 'and TeleBT when connected via USB'.
202 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp43249600"></a>Chapter 3. Handling Precautions</h1></div></div></div><p>
203 All Altus Metrum products are sophisticated electronic devices.
204 When handled gently and properly installed in an air-frame, they
205 will deliver impressive results. However, as with all electronic
206 devices, there are some precautions you must take.
208 The Lithium Polymer rechargeable batteries have an
209 extraordinary power density. This is great because we can fly with
210 much less battery mass than if we used alkaline batteries or previous
211 generation rechargeable batteries... but if they are punctured
212 or their leads are allowed to short, they can and will release their
214 Thus we recommend that you take some care when handling our batteries
215 and consider giving them some extra protection in your air-frame. We
216 often wrap them in suitable scraps of closed-cell packing foam before
217 strapping them down, for example.
219 The barometric sensors used on all of our flight computers are
220 sensitive to sunlight. In normal mounting situations, the baro sensor
221 and all of the other surface mount components
222 are “down” towards whatever the underlying mounting surface is, so
223 this is not normally a problem. Please consider this when designing an
224 installation in an air-frame with a see-through plastic payload bay. It
225 is particularly important to
226 consider this with TeleMini v1.0, both because the baro sensor is on the
227 “top” of the board, and because many model rockets with payload bays
228 use clear plastic for the payload bay! Replacing these with an opaque
229 cardboard tube, painting them, or wrapping them with a layer of masking
230 tape are all reasonable approaches to keep the sensor out of direct
233 The barometric sensor sampling port must be able to “breathe”,
234 both by not being covered by foam or tape or other materials that might
235 directly block the hole on the top of the sensor, and also by having a
236 suitable static vent to outside air.
238 As with all other rocketry electronics, Altus Metrum altimeters must
239 be protected from exposure to corrosive motor exhaust and ejection
241 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp43255088"></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="#idp43255760">1. General Usage Instructions</a></span></dt><dd><dl><dt><span class="section"><a href="#idp43257728">1.1. Hooking Up Lithium Polymer Batteries</a></span></dt><dt><span class="section"><a href="#idp43260736">1.2. Hooking Up Pyro Charges</a></span></dt><dt><span class="section"><a href="#idp43262816">1.3. Hooking Up a Power Switch</a></span></dt><dt><span class="section"><a href="#idp43266032">1.4. Using a Separate Pyro Battery</a></span></dt><dt><span class="section"><a href="#idp43268544">1.5. Using a Different Kind of Battery</a></span></dt></dl></dd><dt><span class="section"><a href="#idp43270288">2. Specifications</a></span></dt><dt><span class="section"><a href="#idp48828432">3. TeleMetrum</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48831824">3.1. TeleMetrum Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp48861136">3.2. Using a Separate Pyro Battery with TeleMetrum</a></span></dt><dt><span class="section"><a href="#idp48864384">3.3. Using an Active Switch with TeleMetrum</a></span></dt></dl></dd><dt><span class="section"><a href="#idp48866512">4. TeleMini v1.0</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48871408">4.1. TeleMini v1.0 Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp48890752">4.2. Using a Separate Pyro Battery with TeleMini v1.0</a></span></dt><dt><span class="section"><a href="#idp48894128">4.3. Using an Active Switch with TeleMini v1.0</a></span></dt></dl></dd><dt><span class="section"><a href="#idp48896336">5. TeleMini v2.0</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48900352">5.1. TeleMini v2.0 Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp48922736">5.2. Using a Separate Pyro Battery with TeleMini v2.0</a></span></dt><dt><span class="section"><a href="#idp48925936">5.3. Using an Active Switch with TeleMini v2.0</a></span></dt></dl></dd><dt><span class="section"><a href="#idp48928032">6. EasyMini</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48931888">6.1. EasyMini Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp48954272">6.2. Using a Separate Pyro Battery with EasyMini</a></span></dt><dt><span class="section"><a href="#idp48957456">6.3. Using an Active Switch with EasyMini</a></span></dt></dl></dd><dt><span class="section"><a href="#idp48959552">7. TeleMega</a></span></dt><dd><dl><dt><span class="section"><a href="#idp48963520">7.1. TeleMega Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp49001024">7.2. Using a Separate Pyro Battery with TeleMega</a></span></dt><dt><span class="section"><a href="#idp49002624">7.3. Using Only One Battery With TeleMega</a></span></dt><dt><span class="section"><a href="#idp49004544">7.4. Using an Active Switch with TeleMega</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49006592">8. EasyMega</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49010560">8.1. EasyMega Screw Terminals</a></span></dt><dt><span class="section"><a href="#idp49048064">8.2. Using a Separate Pyro Battery with EasyMega</a></span></dt><dt><span class="section"><a href="#idp49049664">8.3. Using Only One Battery With EasyMega</a></span></dt><dt><span class="section"><a href="#idp49051584">8.4. Using an Active Switch with EasyMega</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49053632">9. Flight Data Recording</a></span></dt><dt><span class="section"><a href="#idp49084400">10. Installation</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp43255760"></a>1. General Usage Instructions</h2></div></div></div><p>
242 Here are general instructions for hooking up an Altus Metrum
243 flight computer. Instructions specific to each model will be
244 found in the section devoted to that model below.
246 To prevent electrical interference from affecting the
247 operation of the flight computer, it's important to always
248 twist pairs of wires connected to the board. Twist the switch
249 leads, the pyro leads and the battery leads. This reduces
250 interference through a mechanism called common mode rejection.
251 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp43257728"></a>1.1. Hooking Up Lithium Polymer Batteries</h3></div></div></div><p>
252 All Altus Metrum flight computers have a two pin JST PH
253 series connector to connect up a single-cell Lithium Polymer
254 cell (3.7V nominal). You can purchase matching batteries
255 from the Altus Metrum store, or other vendors, or you can
256 make your own. Pin 1 of the connector is positive, pin 2 is
257 negative. Spark Fun sells a cable with the connector
258 attached, which they call a <a class="ulink" href="https://www.sparkfun.com/products/9914" target="_top">JST Jumper 2
261 Many RC vendors also sell lithium polymer batteries with
262 this same connector. All that we have found use the opposite
263 polarity, and if you use them that way, you will damage or
264 destroy the flight computer.
265 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp43260736"></a>1.2. Hooking Up Pyro Charges</h3></div></div></div><p>
266 Altus Metrum flight computers always have two screws for
267 each pyro charge. This means you shouldn't need to put two
268 wires into a screw terminal or connect leads from pyro
269 charges together externally.
271 On the flight computer, one lead from each charge is hooked
272 to the positive battery terminal through the power switch.
273 The other lead is connected through the pyro circuit, which
274 is connected to the negative battery terminal when the pyro
276 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp43262816"></a>1.3. Hooking Up a Power Switch</h3></div></div></div><p>
277 Altus Metrum flight computers need an external power switch
278 to turn them on. This disconnects both the computer and the
279 pyro charges from the battery, preventing the charges from
280 firing when in the Off position. The switch is in-line with
281 the positive battery terminal.
282 </p><div class="section"><div class="titlepage"><div><div><h4 class="title"><a name="idp43264192"></a>1.3.1. Using an External Active Switch Circuit</h4></div></div></div><p>
283 You can use an active switch circuit, such as the
284 Featherweight Magnetic Switch, with any Altus Metrum
285 flight computer. These require three connections, one to
286 the battery, one to the positive power input on the flight
287 computer and one to ground. Find instructions on how to
288 hook these up for each flight computer below. The follow
289 the instructions that come with your active switch to
291 </p></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp43266032"></a>1.4. Using a Separate Pyro Battery</h3></div></div></div><p>
292 As mentioned above in the section on hooking up pyro
293 charges, one lead for each of the pyro charges is connected
294 through the power switch directly to the positive battery
295 terminal. The other lead is connected to the pyro circuit,
296 which connects it to the negative battery terminal when the
297 pyro circuit is fired. The pyro circuit on all of the flight
298 computers is designed to handle up to 16V.
300 To use a separate pyro battery, connect the negative pyro
301 battery terminal to the flight computer ground terminal,
302 the positive battery terminal to the igniter and the other
303 igniter lead to the negative pyro terminal on the flight
304 computer. When the pyro channel fires, it will complete the
305 circuit between the negative pyro terminal and the ground
306 terminal, firing the igniter. Specific instructions on how
307 to hook this up will be found in each section below.
308 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp43268544"></a>1.5. Using a Different Kind of Battery</h3></div></div></div><p>
309 EasyMini and TeleMini v2 are designed to use either a
310 lithium polymer battery or any other battery producing
311 between 4 and 12 volts, such as a rectangular 9V
312 battery. TeleMega, EasyMega and TeleMetrum are not designed for this,
313 and must only be powered by a lithium polymer battery. Find
314 instructions on how to use other batteries in the EasyMini
315 and TeleMini sections below.
316 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp43270288"></a>2. Specifications</h2></div></div></div><p>
317 Here's the full set of Altus Metrum products, both in
318 production and retired.
319 </p><div class="table"><a name="idp48750064"></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="idp48804240"></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>
325 </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>
329 </p></td><td align="center"><p>
332 </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>
337 </p></td><td align="center"><p>
342 </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>
346 </p></td><td align="center"><p>
351 </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>
357 </p></td><td align="center"><p>
363 </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>
368 </p></td><td align="center"><p>
374 </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="idp48828432"></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>
375 TeleMetrum is a 1 inch by 2¾ inch circuit board. It was designed to
376 fit inside coupler for 29mm air-frame tubing, but using it in a tube that
377 small in diameter may require some creativity in mounting and wiring
378 to succeed! The presence of an accelerometer means TeleMetrum should
379 be aligned along the flight axis of the airframe, and by default the ¼
380 wave UHF wire antenna should be on the nose-cone end of the board. The
381 antenna wire is about 7 inches long, and wiring for a power switch and
382 the e-matches for apogee and main ejection charges depart from the
383 fin can end of the board, meaning an ideal “simple” avionics
384 bay for TeleMetrum should have at least 10 inches of interior length.
385 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48831824"></a>3.1. TeleMetrum Screw Terminals</h3></div></div></div><p>
386 TeleMetrum has six screw terminals on the end of the board
387 opposite the telemetry antenna. Two are for the power
388 switch, and two each for the apogee and main igniter
389 circuits. Using the picture above and starting from the top,
390 the terminals are as follows:
391 </p><div class="table"><a name="idp43191248"></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="idp48861136"></a>3.2. Using a Separate Pyro Battery with TeleMetrum</h3></div></div></div><p>
392 As described above, using an external pyro battery involves
393 connecting the negative battery terminal to the flight
394 computer ground, connecting the positive battery terminal to
395 one of the igniter leads and connecting the other igniter
396 lead to the per-channel pyro circuit connection.
398 To connect the negative battery terminal to the TeleMetrum
399 ground, insert a small piece of wire, 24 to 28 gauge
400 stranded, into the GND hole just above the screw terminal
401 strip and solder it in place.
403 Connecting the positive battery terminal to the pyro
404 charges must be done separate from TeleMetrum, by soldering
405 them together or using some other connector.
407 The other lead from each pyro charge is then inserted into
408 the appropriate per-pyro channel screw terminal (terminal 4 for the
409 Main charge, terminal 6 for the Apogee charge).
410 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48864384"></a>3.3. Using an Active Switch with TeleMetrum</h3></div></div></div><p>
411 As explained above, an external active switch requires three
412 connections, one to the positive battery terminal, one to
413 the flight computer positive input and one to ground.
415 The positive battery terminal is available on screw terminal
416 2, the positive flight computer input is on terminal 1. To
417 hook a lead to ground, solder a piece of wire, 24 to 28
418 gauge stranded, to the GND hole just above terminal 1.
419 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp48866512"></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>
420 TeleMini v1.0 is ½ inches by 1½ inches. It was
421 designed to fit inside an 18mm air-frame tube, but using it in
422 a tube that small in diameter may require some creativity in
423 mounting and wiring to succeed! Since there is no
424 accelerometer, TeleMini can be mounted in any convenient
425 orientation. The default ¼ wave UHF wire antenna attached to
426 the center of one end of the board is about 7 inches long. Two
427 wires for the power switch are connected to holes in the
428 middle of the board. Screw terminals for the e-matches for
429 apogee and main ejection charges depart from the other end of
430 the board, meaning an ideal “simple” avionics bay for TeleMini
431 should have at least 9 inches of interior length.
432 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48871408"></a>4.1. TeleMini v1.0 Screw Terminals</h3></div></div></div><p>
433 TeleMini v1.0 has four screw terminals on the end of the
434 board opposite the telemetry antenna. Two are for the apogee
435 and two are for main igniter circuits. There are also wires
436 soldered to the board for the power switch. Using the
437 picture above and starting from the top for the terminals
438 and from the left for the power switch wires, the
439 connections are as follows:
440 </p><div class="table"><a name="idp48872848"></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="idp48890752"></a>4.2. Using a Separate Pyro Battery with TeleMini v1.0</h3></div></div></div><p>
441 As described above, using an external pyro battery involves
442 connecting the negative battery terminal to the flight
443 computer ground, connecting the positive battery terminal to
444 one of the igniter leads and connecting the other igniter
445 lead to the per-channel pyro circuit connection. Because
446 there is no solid ground connection to use on TeleMini, this
449 The only available ground connection on TeleMini v1.0 are
450 the two mounting holes next to the telemetry
451 antenna. Somehow connect a small piece of wire to one of
452 those holes and hook it to the negative pyro battery terminal.
454 Connecting the positive battery terminal to the pyro
455 charges must be done separate from TeleMini v1.0, by soldering
456 them together or using some other connector.
458 The other lead from each pyro charge is then inserted into
459 the appropriate per-pyro channel screw terminal (terminal 3 for the
460 Main charge, terminal 1 for the Apogee charge).
461 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48894128"></a>4.3. Using an Active Switch with TeleMini v1.0</h3></div></div></div><p>
462 As explained above, an external active switch requires three
463 connections, one to the positive battery terminal, one to
464 the flight computer positive input and one to ground. Again,
465 because TeleMini doesn't have any good ground connection,
466 this is not recommended.
468 The positive battery terminal is available on the Right
469 power switch wire, the positive flight computer input is on
470 the left power switch wire. Hook a lead to either of the
471 mounting holes for a ground connection.
472 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp48896336"></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>
473 TeleMini v2.0 is 0.8 inches by 1½ inches. It adds more
474 on-board data logging memory, a built-in USB connector and
475 screw terminals for the battery and power switch. The larger
476 board fits in a 24mm coupler. There's also a battery connector
477 for a LiPo battery if you want to use one of those.
478 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48900352"></a>5.1. TeleMini v2.0 Screw Terminals</h3></div></div></div><p>
479 TeleMini v2.0 has two sets of four screw terminals on the end of the
480 board opposite the telemetry antenna. Using the picture
481 above, the top four have connections for the main pyro
482 circuit and an external battery and the bottom four have
483 connections for the apogee pyro circuit and the power
484 switch. Counting from the left, the connections are as follows:
485 </p><div class="table"><a name="idp48901760"></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
486 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="idp48922736"></a>5.2. Using a Separate Pyro Battery with TeleMini v2.0</h3></div></div></div><p>
487 As described above, using an external pyro battery involves
488 connecting the negative battery terminal to the flight
489 computer ground, connecting the positive battery terminal to
490 one of the igniter leads and connecting the other igniter
491 lead to the per-channel pyro circuit connection.
493 To connect the negative pyro battery terminal to TeleMini
494 ground, connect it to the negative external battery
495 connection, top terminal 4.
497 Connecting the positive battery terminal to the pyro
498 charges must be done separate from TeleMini v2.0, by soldering
499 them together or using some other connector.
501 The other lead from each pyro charge is then inserted into
502 the appropriate per-pyro channel screw terminal (top
503 terminal 1 for the Main charge, bottom terminal 1 for the
505 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48925936"></a>5.3. Using an Active Switch with TeleMini v2.0</h3></div></div></div><p>
506 As explained above, an external active switch requires three
507 connections, one to the positive battery terminal, one to
508 the flight computer positive input and one to ground. Use
509 the negative external battery connection, top terminal 4 for
512 The positive battery terminal is available on bottom
513 terminal 4, the positive flight computer input is on the
515 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp48928032"></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>
516 EasyMini is built on a 0.8 inch by 1½ inch circuit board. It's
517 designed to fit in a 24mm coupler tube. The connectors and
518 screw terminals match TeleMini v2.0, so you can easily swap between
519 EasyMini and TeleMini.
520 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48931888"></a>6.1. EasyMini Screw Terminals</h3></div></div></div><p>
521 EasyMini has two sets of four screw terminals on the end of the
522 board opposite the telemetry antenna. Using the picture
523 above, the top four have connections for the main pyro
524 circuit and an external battery and the bottom four have
525 connections for the apogee pyro circuit and the power
526 switch. Counting from the left, the connections are as follows:
527 </p><div class="table"><a name="idp48933296"></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
528 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="idp48954272"></a>6.2. Using a Separate Pyro Battery with EasyMini</h3></div></div></div><p>
529 As described above, using an external pyro battery involves
530 connecting the negative battery terminal to the flight
531 computer ground, connecting the positive battery terminal to
532 one of the igniter leads and connecting the other igniter
533 lead to the per-channel pyro circuit connection.
535 To connect the negative pyro battery terminal to TeleMini
536 ground, connect it to the negative external battery
537 connection, top terminal 4.
539 Connecting the positive battery terminal to the pyro
540 charges must be done separate from EasyMini, by soldering
541 them together or using some other connector.
543 The other lead from each pyro charge is then inserted into
544 the appropriate per-pyro channel screw terminal (top
545 terminal 1 for the Main charge, bottom terminal 1 for the
547 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48957456"></a>6.3. Using an Active Switch with EasyMini</h3></div></div></div><p>
548 As explained above, an external active switch requires three
549 connections, one to the positive battery terminal, one to
550 the flight computer positive input and one to ground. Use
551 the negative external battery connection, top terminal 4 for
554 The positive battery terminal is available on bottom
555 terminal 4, the positive flight computer input is on the
557 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp48959552"></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>
558 TeleMega is a 1¼ inch by 3¼ inch circuit board. It was
559 designed to easily fit in a 38mm coupler. Like TeleMetrum,
560 TeleMega has an accelerometer and so it must be mounted so that
561 the board is aligned with the flight axis. It can be mounted
562 either antenna up or down.
563 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp48963520"></a>7.1. TeleMega Screw Terminals</h3></div></div></div><p>
564 TeleMega has two sets of nine screw terminals on the end of
565 the board opposite the telemetry antenna. They are as follows:
566 </p><div class="table"><a name="idp48964688"></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">
567 Power switch output. Use to connect main battery to
569 </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="idp49001024"></a>7.2. Using a Separate Pyro Battery with TeleMega</h3></div></div></div><p>
570 TeleMega provides explicit support for an external pyro
571 battery. All that is required is to remove the jumper
572 between the lipo terminal (Bottom 3) and the pyro terminal
573 (Bottom 2). Then hook the negative pyro battery terminal to ground
574 (Bottom 1) and the positive pyro battery to the pyro battery
575 input (Bottom 2). You can then use the existing pyro screw
576 terminals to hook up all of the pyro charges.
577 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49002624"></a>7.3. Using Only One Battery With TeleMega</h3></div></div></div><p>
578 Because TeleMega has built-in support for a separate pyro
579 battery, if you want to fly with just one battery running
580 both the computer and firing the charges, you need to
581 connect the flight computer battery to the pyro
582 circuit. TeleMega has two screw terminals for this—hook a
583 wire from the Lipo terminal (Bottom 3) to the Pyro terminal
585 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49004544"></a>7.4. Using an Active Switch with TeleMega</h3></div></div></div><p>
586 As explained above, an external active switch requires three
587 connections, one to the positive battery terminal, one to
588 the flight computer positive input and one to ground.
590 The positive battery terminal is available on Top terminal
591 1, the positive flight computer input is on Top terminal
592 2. Ground is on Top terminal 3.
593 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49006592"></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>
594 EasyMega is a 1¼ inch by 2¼ inch circuit board. It was
595 designed to easily fit in a 38mm coupler. Like TeleMetrum,
596 EasyMega has an accelerometer and so it must be mounted so that
597 the board is aligned with the flight axis. It can be mounted
598 either antenna up or down.
599 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49010560"></a>8.1. EasyMega Screw Terminals</h3></div></div></div><p>
600 EasyMega has two sets of nine screw terminals on the end of
601 the board opposite the telemetry antenna. They are as follows:
602 </p><div class="table"><a name="idp49011728"></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">
603 Power switch output. Use to connect main battery to
605 </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="idp49048064"></a>8.2. Using a Separate Pyro Battery with EasyMega</h3></div></div></div><p>
606 EasyMega provides explicit support for an external pyro
607 battery. All that is required is to remove the jumper
608 between the lipo terminal (Bottom 3) and the pyro terminal
609 (Bottom 2). Then hook the negative pyro battery terminal to ground
610 (Bottom 1) and the positive pyro battery to the pyro battery
611 input (Bottom 2). You can then use the existing pyro screw
612 terminals to hook up all of the pyro charges.
613 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49049664"></a>8.3. Using Only One Battery With EasyMega</h3></div></div></div><p>
614 Because EasyMega has built-in support for a separate pyro
615 battery, if you want to fly with just one battery running
616 both the computer and firing the charges, you need to
617 connect the flight computer battery to the pyro
618 circuit. EasyMega has two screw terminals for this—hook a
619 wire from the Lipo terminal (Bottom 3) to the Pyro terminal
621 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49051584"></a>8.4. Using an Active Switch with EasyMega</h3></div></div></div><p>
622 As explained above, an external active switch requires three
623 connections, one to the positive battery terminal, one to
624 the flight computer positive input and one to ground.
626 The positive battery terminal is available on Top terminal
627 1, the positive flight computer input is on Top terminal
628 2. Ground is on Top terminal 3.
629 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49053632"></a>9. Flight Data Recording</h2></div></div></div><p>
630 Each flight computer logs data at 100 samples per second
631 during ascent and 10 samples per second during descent, except
632 for TeleMini v1.0, which records ascent at 10 samples per
633 second and descent at 1 sample per second. Data are logged to
634 an on-board flash memory part, which can be partitioned into
635 several equal-sized blocks, one for each flight.
636 </p><div class="table"><a name="idp49055040"></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>
637 The on-board flash is partitioned into separate flight logs,
638 each of a fixed maximum size. Increase the maximum size of
639 each log and you reduce the number of flights that can be
640 stored. Decrease the size and you can store more flights.
642 Configuration data is also stored in the flash memory on
643 TeleMetrum v1.x, TeleMini and EasyMini. This consumes 64kB
644 of flash space. This configuration space is not available
645 for storing flight log data. TeleMetrum v2.0, TeleMega and EasyMega
646 store configuration data in a bit of eeprom available within
647 the processor chip, leaving that space available in flash for
650 To compute the amount of space needed for a single flight, you
651 can multiply the expected ascent time (in seconds) by 100
652 times bytes-per-sample, multiply the expected descent time (in
653 seconds) by 10 times the bytes per sample and add the two
654 together. That will slightly under-estimate the storage (in
655 bytes) needed for the flight. For instance, a TeleMetrum v2.0 flight spending
656 20 seconds in ascent and 150 seconds in descent will take
657 about (20 * 1600) + (150 * 160) = 56000 bytes of storage. You
658 could store dozens of these flights in the on-board flash.
660 The default size allows for several flights on each flight
661 computer, except for TeleMini v1.0, which only holds data for a
662 single flight. You can adjust the size.
664 Altus Metrum flight computers will not overwrite existing
665 flight data, so be sure to download flight data and erase it
666 from the flight computer before it fills up. The flight
667 computer will still successfully control the flight even if it
668 cannot log data, so the only thing you will lose is the data.
669 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49084400"></a>10. Installation</h2></div></div></div><p>
670 A typical installation involves attaching
671 only a suitable battery, a single pole switch for
672 power on/off, and two pairs of wires connecting e-matches for the
673 apogee and main ejection charges. All Altus Metrum products are
674 designed for use with single-cell batteries with 3.7 volts
675 nominal. TeleMini v2.0 and EasyMini may also be used with other
676 batteries as long as they supply between 4 and 12 volts.
678 The battery connectors are a standard 2-pin JST connector and
679 match batteries sold by Spark Fun. These batteries are
680 single-cell Lithium Polymer batteries that nominally provide 3.7
681 volts. Other vendors sell similar batteries for RC aircraft
682 using mating connectors, however the polarity for those is
683 generally reversed from the batteries used by Altus Metrum
684 products. In particular, the Tenergy batteries supplied for use
685 in Featherweight flight computers are not compatible with Altus
686 Metrum flight computers or battery chargers. <span class="emphasis"><em>Check
687 polarity and voltage before connecting any battery not purchased
688 from Altus Metrum or Spark Fun.</em></span>
690 By default, we use the unregulated output of the battery directly
691 to fire ejection charges. This works marvelously with standard
692 low-current e-matches like the J-Tek from MJG Technologies, and with
693 Quest Q2G2 igniters. However, if you want or need to use a separate
694 pyro battery, check out the “External Pyro Battery” section in this
695 manual for instructions on how to wire that up. The altimeters are
696 designed to work with an external pyro battery of no more than 15 volts.
698 Ejection charges are wired directly to the screw terminal block
699 at the aft end of the altimeter. You'll need a very small straight
700 blade screwdriver for these screws, such as you might find in a
701 jeweler's screwdriver set.
703 Except for TeleMini v1.0, the flight computers also use the
704 screw terminal block for the power switch leads. On TeleMini v1.0,
705 the power switch leads are soldered directly to the board and
706 can be connected directly to a switch.
708 For most air-frames, the integrated antennas are more than
709 adequate. However, if you are installing in a carbon-fiber or
710 metal electronics bay which is opaque to RF signals, you may need to
711 use off-board external antennas instead. In this case, you can
712 replace the stock UHF antenna wire with an edge-launched SMA connector,
713 and, on TeleMetrum v1, you can unplug the integrated GPS
714 antenna and select an appropriate off-board GPS antenna with
715 cable terminating in a U.FL connector.
716 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49091680"></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="#idp49092320">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp49160720">2. GPS </a></span></dt><dt><span class="section"><a href="#idp49163504">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp49174800">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp49177552">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp49181552">6. APRS</a></span></dt><dt><span class="section"><a href="#idp49205872">7. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49207792">7.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp49209840">7.2. Callsign</a></span></dt><dt><span class="section"><a href="#idp49211376">7.3. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp49212672">7.4. Telemetry baud rate</a></span></dt><dt><span class="section"><a href="#idp49214240">7.5. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp49215712">7.6. APRS SSID</a></span></dt><dt><span class="section"><a href="#idp49217056">7.7. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp49219648">7.8. Apogee Lockout</a></span></dt><dt><span class="section"><a href="#idp49221376">7.9. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp49223072">7.10. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp49225216">7.11. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp49227328">7.12. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp49229568">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="idp49092320"></a>1. Firmware Modes </h2></div></div></div><p>
717 The AltOS firmware build for the altimeters has two
718 fundamental modes, “idle” and “flight”. Which of these modes
719 the firmware operates in is determined at start up time. For
720 TeleMetrum, TeleMega and EasyMega, which have accelerometers, the mode is
721 controlled by the orientation of the
722 rocket (well, actually the board, of course...) at the time
723 power is switched on. If the rocket is “nose up”, then
724 the flight computer assumes it's on a rail or rod being prepared for
725 launch, so the firmware chooses flight mode. However, if the
726 rocket is more or less horizontal, the firmware instead enters
727 idle mode. Since TeleMini v2.0 and EasyMini don't have an
728 accelerometer we can use to determine orientation, “idle” mode
729 is selected if the board is connected via USB to a computer,
730 otherwise the board enters “flight” mode. TeleMini v1.0
731 selects “idle” mode if it receives a command packet within the
732 first five seconds of operation.
734 At power on, the altimeter will beep out the battery voltage
735 to the nearest tenth of a volt. Each digit is represented by
736 a sequence of short “dit” beeps, with a pause between
737 digits. A zero digit is represented with one long “dah”
738 beep. Then there will be a short pause while the altimeter
739 completes initialization and self test, and decides which mode
742 Here's a short summary of all of the modes and the beeping (or
743 flashing, in the case of TeleMini v1) that accompanies each
744 mode. In the description of the beeping pattern, “dit” means a
745 short beep while "dah" means a long beep (three times as
746 long). “Brap” means a long dissonant tone.
747 </p><div class="table"><a name="idp49097680"></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">
749 Calibrating sensors, detecting orientation.
751 </td></tr><tr><td align="center">Idle</td><td align="center">I</td><td align="center">dit dit</td><td align="center">
753 Ready to accept commands over USB or radio link.
755 </td></tr><tr><td align="center">Pad</td><td align="center">P</td><td align="center">dit dah dah dit</td><td align="center">
757 Waiting for launch. Not listening for commands.
759 </td></tr><tr><td align="center">Boost</td><td align="center">B</td><td align="center">dah dit dit dit</td><td align="center">
761 Accelerating upwards.
763 </td></tr><tr><td align="center">Fast</td><td align="center">F</td><td align="center">dit dit dah dit</td><td align="center">
765 Decelerating, but moving faster than 200m/s.
767 </td></tr><tr><td align="center">Coast</td><td align="center">C</td><td align="center">dah dit dah dit</td><td align="center">
769 Decelerating, moving slower than 200m/s
771 </td></tr><tr><td align="center">Drogue</td><td align="center">D</td><td align="center">dah dit dit</td><td align="center">
773 Descending after apogee. Above main height.
775 </td></tr><tr><td align="center">Main</td><td align="center">M</td><td align="center">dah dah</td><td align="center">
777 Descending. Below main height.
779 </td></tr><tr><td align="center">Landed</td><td align="center">L</td><td align="center">dit dah dit dit</td><td align="center">
781 Stable altitude for at least ten seconds.
783 </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">
785 Error detected during sensor calibration.
787 </td></tr></tbody></table></div></div><p><br class="table-break">
789 In flight or “pad” mode, the altimeter engages the flight
790 state machine, goes into transmit-only mode to send telemetry,
791 and waits for launch to be detected. Flight mode is indicated
792 by an “di-dah-dah-dit” (“P” for pad) on the beeper or lights,
793 followed by beeps or flashes indicating the state of the
794 pyrotechnic igniter continuity. One beep/flash indicates
795 apogee continuity, two beeps/flashes indicate main continuity,
796 three beeps/flashes indicate both apogee and main continuity,
797 and one longer “brap” sound which is made by rapidly
798 alternating between two tones indicates no continuity. For a
799 dual deploy flight, make sure you're getting three beeps or
800 flashes before launching! For apogee-only or motor eject
801 flights, do what makes sense.
803 If idle mode is entered, you will hear an audible “di-dit” or
804 see two short flashes (“I” for idle), and the flight state
805 machine is disengaged, thus no ejection charges will fire.
806 The altimeters also listen for the radio link when in idle
807 mode for requests sent via TeleDongle. Commands can be issued
808 in idle mode over either USB or the radio link
809 equivalently. TeleMini v1.0 only has the radio link. Idle
810 mode is useful for configuring the altimeter, for extracting
811 data from the on-board storage chip after flight, and for
812 ground testing pyro charges.
814 In “Idle” and “Pad” modes, once the mode indication
815 beeps/flashes and continuity indication has been sent, if
816 there is no space available to log the flight in on-board
817 memory, the flight computer will emit a warbling tone (much
818 slower than the “no continuity tone”)
820 Here's a summary of all of the “pad” and “idle” mode indications.
821 </p><div class="table"><a name="idp49134768"></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">
823 No continuity detected on either apogee or main
826 </td></tr><tr><td align="center">Apogee</td><td align="center">dit</td><td align="center">
828 Continuity detected only on apogee igniter.
830 </td></tr><tr><td align="center">Main</td><td align="center">dit dit</td><td align="center">
832 Continuity detected only on main igniter.
834 </td></tr><tr><td align="center">Both</td><td align="center">dit dit dit</td><td align="center">
836 Continuity detected on both igniters.
838 </td></tr><tr><td align="center">Storage Full</td><td align="center">warble</td><td align="center">
840 On-board data logging storage is full. This will
841 not prevent the flight computer from safely
842 controlling the flight or transmitting telemetry
843 signals, but no record of the flight will be
844 stored in on-board flash.
846 </td></tr></tbody></table></div></div><p><br class="table-break">
848 Once landed, the flight computer will signal that by emitting
849 the “Landed” sound described above, after which it will beep
850 out the apogee height (in meters). Each digit is represented
851 by a sequence of short “dit” beeps, with a pause between
852 digits. A zero digit is represented with one long “dah”
853 beep. The flight computer will continue to report landed mode
854 and beep out the maximum height until turned off.
856 One “neat trick” of particular value when TeleMetrum, TeleMega
857 or EasyMega are used with
858 very large air-frames, is that you can power the board up while the
859 rocket is horizontal, such that it comes up in idle mode. Then you can
860 raise the air-frame to launch position, and issue a 'reset' command
861 via TeleDongle over the radio link to cause the altimeter to reboot and
862 come up in flight mode. This is much safer than standing on the top
863 step of a rickety step-ladder or hanging off the side of a launch
864 tower with a screw-driver trying to turn on your avionics before
867 TeleMini v1.0 is configured solely via the radio link. Of course, that
868 means you need to know the TeleMini radio configuration values
869 or you won't be able to communicate with it. For situations
870 when you don't have the radio configuration values, TeleMini v1.0
871 offers an 'emergency recovery' mode. In this mode, TeleMini is
872 configured as follows:
873 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
874 Sets the radio frequency to 434.550MHz
875 </p></li><li class="listitem"><p>
876 Sets the radio calibration back to the factory value.
877 </p></li><li class="listitem"><p>
878 Sets the callsign to N0CALL
879 </p></li><li class="listitem"><p>
880 Does not go to 'pad' mode after five seconds.
881 </p></li></ul></div><p>
883 To get into 'emergency recovery' mode, first find the row of
884 four small holes opposite the switch wiring. Using a short
885 piece of small gauge wire, connect the outer two holes
886 together, then power TeleMini up. Once the red LED is lit,
887 disconnect the wire and the board should signal that it's in
888 'idle' mode after the initial five second startup period.
889 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49160720"></a>2. GPS </h2></div></div></div><p>
890 TeleMetrum and TeleMega include a complete GPS receiver. A
891 complete explanation of how GPS works is beyond the scope of
892 this manual, but the bottom line is that the GPS receiver
893 needs to lock onto at least four satellites to obtain a solid
894 3 dimensional position fix and know what time it is.
896 The flight computers provide backup power to the GPS chip any time a
897 battery is connected. This allows the receiver to “warm start” on
898 the launch rail much faster than if every power-on were a GPS
899 “cold start”. In typical operations, powering up
900 on the flight line in idle mode while performing final air-frame
901 preparation will be sufficient to allow the GPS receiver to cold
902 start and acquire lock. Then the board can be powered down during
903 RSO review and installation on a launch rod or rail. When the board
904 is turned back on, the GPS system should lock very quickly, typically
905 long before igniter installation and return to the flight line are
907 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49163504"></a>3. Controlling An Altimeter Over The Radio Link</h2></div></div></div><p>
908 One of the unique features of the Altus Metrum system is the
909 ability to create a two way command link between TeleDongle
910 and an altimeter using the digital radio transceivers
911 built into each device. This allows you to interact with the
912 altimeter from afar, as if it were directly connected to the
915 Any operation which can be performed with a flight computer can
916 either be done with the device directly connected to the
917 computer via the USB cable, or through the radio
918 link. TeleMini v1.0 doesn't provide a USB connector and so it is
919 always communicated with over radio. Select the appropriate
920 TeleDongle device when the list of devices is presented and
921 AltosUI will interact with an altimeter over the radio link.
923 One oddity in the current interface is how AltosUI selects the
924 frequency for radio communications. Instead of providing
925 an interface to specifically configure the frequency, it uses
926 whatever frequency was most recently selected for the target
927 TeleDongle device in Monitor Flight mode. If you haven't ever
928 used that mode with the TeleDongle in question, select the
929 Monitor Flight button from the top level UI, and pick the
930 appropriate TeleDongle device. Once the flight monitoring
931 window is open, select the desired frequency and then close it
932 down again. All radio communications will now use that frequency.
933 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
934 Save Flight Data—Recover flight data from the rocket without
936 </p></li><li class="listitem"><p>
937 Configure altimeter apogee delays, main deploy heights
938 and additional pyro event conditions
939 to respond to changing launch conditions. You can also
940 'reboot' the altimeter. Use this to remotely enable the
941 flight computer by turning TeleMetrum or TeleMega on in “idle” mode,
942 then once the air-frame is oriented for launch, you can
943 reboot the altimeter and have it restart in pad mode
944 without having to climb the scary ladder.
945 </p></li><li class="listitem"><p>
946 Fire Igniters—Test your deployment charges without snaking
947 wires out through holes in the air-frame. Simply assemble the
948 rocket as if for flight with the apogee and main charges
949 loaded, then remotely command the altimeter to fire the
951 </p></li></ul></div><p>
952 Operation over the radio link for configuring an altimeter, ground
953 testing igniters, and so forth uses the same RF frequencies as flight
954 telemetry. To configure the desired TeleDongle frequency, select
955 the monitor flight tab, then use the frequency selector and
956 close the window before performing other desired radio operations.
958 The flight computers only enable radio commanding in 'idle' mode.
959 TeleMetrum and TeleMega use the accelerometer to detect which orientation they
960 start up in, so make sure you have the flight computer lying horizontally when you turn
961 it on. Otherwise, it will start in 'pad' mode ready for
962 flight, and will not be listening for command packets from TeleDongle.
964 TeleMini listens for a command packet for five seconds after
965 first being turned on, if it doesn't hear anything, it enters
966 'pad' mode, ready for flight and will no longer listen for
967 command packets. The easiest way to connect to TeleMini is to
968 initiate the command and select the TeleDongle device. At this
969 point, the TeleDongle will be attempting to communicate with
970 the TeleMini. Now turn TeleMini on, and it should immediately
971 start communicating with the TeleDongle and the desired
972 operation can be performed.
974 You can monitor the operation of the radio link by watching the
975 lights on the devices. The red LED will flash each time a packet
976 is transmitted, while the green LED will light up on TeleDongle when
977 it is waiting to receive a packet from the altimeter.
978 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49174800"></a>4. Ground Testing </h2></div></div></div><p>
979 An important aspect of preparing a rocket using electronic deployment
980 for flight is ground testing the recovery system. Thanks
981 to the bi-directional radio link central to the Altus Metrum system,
982 this can be accomplished in a TeleMega, TeleMetrum or TeleMini equipped rocket
983 with less work than you may be accustomed to with other systems. It
986 Just prep the rocket for flight, then power up the altimeter
987 in “idle” mode (placing air-frame horizontal for TeleMetrum or TeleMega, or
988 selecting the Configure Altimeter tab for TeleMini). This will cause
989 the firmware to go into “idle” mode, in which the normal flight
990 state machine is disabled and charges will not fire without
991 manual command. You can now command the altimeter to fire the apogee
992 or main charges from a safe distance using your computer and
993 TeleDongle and the Fire Igniter tab to complete ejection testing.
994 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49177552"></a>5. Radio Link </h2></div></div></div><p>
995 Our flight computers all incorporate an RF transceiver, but
996 it's not a full duplex system... each end can only be transmitting or
997 receiving at any given moment. So we had to decide how to manage the
1000 By design, the altimeter firmware listens for the radio link when
1001 it's in “idle mode”, which
1002 allows us to use the radio link to configure the rocket, do things like
1003 ejection tests, and extract data after a flight without having to
1004 crack open the air-frame. However, when the board is in “flight
1005 mode”, the altimeter only
1006 transmits and doesn't listen at all. That's because we want to put
1007 ultimate priority on event detection and getting telemetry out of
1009 the radio in case the rocket crashes and we aren't able to extract
1012 We don't generally use a 'normal packet radio' mode like APRS
1013 because they're just too inefficient. The GFSK modulation we
1014 use is FSK with the base-band pulses passed through a Gaussian
1015 filter before they go into the modulator to limit the
1016 transmitted bandwidth. When combined with forward error
1017 correction and interleaving, this allows us to have a very
1018 robust 19.2 kilobit data link with only 10-40 milliwatts of
1019 transmit power, a whip antenna in the rocket, and a hand-held
1020 Yagi on the ground. We've had flights to above 21k feet AGL
1021 with great reception, and calculations suggest we should be
1022 good to well over 40k feet AGL with a 5-element yagi on the
1023 ground with our 10mW units and over 100k feet AGL with the
1024 40mW devices. We hope to fly boards to higher altitudes over
1025 time, and would of course appreciate customer feedback on
1026 performance in higher altitude flights!
1027 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49181552"></a>6. APRS</h2></div></div></div><p>
1028 TeleMetrum v2.0 and TeleMega can send APRS if desired, and the
1029 interval between APRS packets can be configured. As each APRS
1030 packet takes a full second to transmit, we recommend an
1031 interval of at least 5 seconds to avoid consuming too much
1032 battery power or radio channel bandwidth. You can configure
1033 the APRS interval using AltosUI; that process is described in
1034 the Configure Altimeter section of the AltosUI chapter.
1036 AltOS uses the APRS compressed position report data format,
1037 which provides for higher position precision and shorter
1038 packets than the original APRS format. It also includes
1039 altitude data, which is invaluable when tracking rockets. We
1040 haven't found a receiver which doesn't handle compressed
1041 positions, but it's just possible that you have one, so if you
1042 have an older device that can receive the raw packets but
1043 isn't displaying position information, it's possible that this
1046 APRS packets include an SSID (Secondary Station Identifier)
1047 field that allows one operator to have multiple
1048 transmitters. AltOS allows you to set this to a single digit
1049 from 0 to 9, allowing you to fly multiple transmitters at the
1050 same time while keeping the identify of each one separate in
1051 the receiver. By default, the SSID is set to the last digit of
1052 the device serial number.
1054 The APRS packet format includes a comment field that can have
1055 arbitrary text in it. AltOS uses this to send status
1056 information about the flight computer. It sends four fields as
1057 shown in the following table.
1058 </p><div class="table"><a name="idp49185360"></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>
1059 Here's an example of an APRS comment showing GPS lock with 6
1060 satellites in view, a primary battery at 4.0V, and
1061 apogee and main igniters both at 3.7V from device 1286.
1062 </p><pre class="screen">
1063 L6 B4.0 A3.7 M3.7 1286
1066 Make sure your primary battery is above 3.8V, any connected
1067 igniters are above 3.5V and GPS is locked with at least 5 or 6
1068 satellites in view before flying. If GPS is switching between
1069 L and U regularly, then it doesn't have a good lock and you
1070 should wait until it becomes stable.
1072 If the GPS receiver loses lock, the APRS data transmitted will
1073 contain the last position for which GPS lock was
1074 available. You can tell that this has happened by noticing
1075 that the GPS status character switches from 'L' to 'U'. Before
1076 GPS has locked, APRS will transmit zero for latitude,
1077 longitude and altitude.
1078 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49205872"></a>7. Configurable Parameters</h2></div></div></div><p>
1079 Configuring an Altus Metrum altimeter for flight is very
1080 simple. Even on our baro-only TeleMini and EasyMini boards,
1081 the use of a Kalman filter means there is no need to set a
1082 “mach delay”. The few configurable parameters can all be set
1083 using AltosUI over USB or or radio link via TeleDongle. Read
1084 the Configure Altimeter section in the AltosUI chapter below
1085 for more information.
1086 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49207792"></a>7.1. Radio Frequency</h3></div></div></div><p>
1087 Altus Metrum boards support radio frequencies in the 70cm
1088 band. By default, the configuration interface provides a
1089 list of 10 “standard” frequencies in 100kHz channels starting at
1090 434.550MHz. However, the firmware supports use of
1091 any 50kHz multiple within the 70cm band. At any given
1092 launch, we highly recommend coordinating when and by whom each
1093 frequency will be used to avoid interference. And of course, both
1094 altimeter and TeleDongle must be configured to the same
1095 frequency to successfully communicate with each other.
1096 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49209840"></a>7.2. Callsign</h3></div></div></div><p>
1097 This sets the callsign used for telemetry, APRS and the
1098 packet link. For telemetry and APRS, this is used to
1099 identify the device. For the packet link, the callsign must
1100 match that configured in AltosUI or the link will not
1101 work. This is to prevent accidental configuration of another
1102 Altus Metrum flight computer operating on the same frequency nearby.
1103 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49211376"></a>7.3. Telemetry/RDF/APRS Enable</h3></div></div></div><p>
1104 You can completely disable the radio while in flight, if
1105 necessary. This doesn't disable the packet link in idle
1107 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49212672"></a>7.4. Telemetry baud rate</h3></div></div></div><p>
1108 This sets the modulation bit rate for data transmission for
1109 both telemetry and packet link mode. Lower bit
1110 rates will increase range while reducing the amount of data
1111 that can be sent and increasing battery consumption. All
1112 telemetry is done using a rate 1/2 constraint 4 convolution
1113 code, so the actual data transmission rate is 1/2 of the
1114 modulation bit rate specified here.
1115 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49214240"></a>7.5. APRS Interval</h3></div></div></div><p>
1116 This selects how often APRS packets are transmitted. Set
1117 this to zero to disable APRS without also disabling the
1118 regular telemetry and RDF transmissions. As APRS takes a
1119 full second to transmit a single position report, we
1120 recommend sending packets no more than once every 5 seconds.
1121 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49215712"></a>7.6. APRS SSID</h3></div></div></div><p>
1122 This selects the SSID reported in APRS packets. By default,
1123 it is set to the last digit of the serial number, but you
1124 can change this to any value from 0 to 9.
1125 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49217056"></a>7.7. Apogee Delay</h3></div></div></div><p>
1126 Apogee delay is the number of seconds after the altimeter detects flight
1127 apogee that the drogue charge should be fired. In most cases, this
1128 should be left at the default of 0. However, if you are flying
1129 redundant electronics such as for an L3 certification, you may wish
1130 to set one of your altimeters to a positive delay so that both
1131 primary and backup pyrotechnic charges do not fire simultaneously.
1133 The Altus Metrum apogee detection algorithm fires exactly at
1134 apogee. If you are also flying an altimeter like the
1135 PerfectFlite MAWD, which only supports selecting 0 or 1
1136 seconds of apogee delay, you may wish to set the MAWD to 0
1137 seconds delay and set the TeleMetrum to fire your backup 2
1138 or 3 seconds later to avoid any chance of both charges
1139 firing simultaneously. We've flown several air-frames this
1140 way quite happily, including Keith's successful L3 cert.
1141 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49219648"></a>7.8. Apogee Lockout</h3></div></div></div><p>
1142 Apogee lockout is the number of seconds after boost where
1143 the flight computer will not fire the apogee charge, even if
1144 the rocket appears to be at apogee. This is often called
1145 'Mach Delay', as it is intended to prevent a flight computer
1146 from unintentionally firing apogee charges due to the pressure
1147 spike that occurrs across a mach transition. Altus Metrum
1148 flight computers include a Kalman filter which is not fooled
1149 by this sharp pressure increase, and so this setting should
1150 be left at the default value of zero to disable it.
1151 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49221376"></a>7.9. Main Deployment Altitude</h3></div></div></div><p>
1152 By default, the altimeter will fire the main deployment charge at an
1153 elevation of 250 meters (about 820 feet) above ground. We think this
1154 is a good elevation for most air-frames, but feel free to change this
1155 to suit. In particular, if you are flying two altimeters, you may
1157 deployment elevation for the backup altimeter to be something lower
1158 than the primary so that both pyrotechnic charges don't fire
1160 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49223072"></a>7.10. Maximum Flight Log</h3></div></div></div><p>
1161 Changing this value will set the maximum amount of flight
1162 log storage that an individual flight will use. The
1163 available storage is divided into as many flights of the
1164 specified size as can fit in the available space. You can
1165 download and erase individual flight logs. If you fill up
1166 the available storage, future flights will not get logged
1167 until you erase some of the stored ones.
1169 Even though our flight computers (except TeleMini v1.0) can store
1170 multiple flights, we strongly recommend downloading and saving
1171 flight data after each flight.
1172 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49225216"></a>7.11. Ignite Mode</h3></div></div></div><p>
1173 Instead of firing one charge at apogee and another charge at
1174 a fixed height above the ground, you can configure the
1175 altimeter to fire both at apogee or both during
1176 descent. This was added to support an airframe Bdale designed that
1177 had two altimeters, one in the fin can and one in the nose.
1179 Providing the ability to use both igniters for apogee or
1180 main allows some level of redundancy without needing two
1181 flight computers. In Redundant Apogee or Redundant Main
1182 mode, the two charges will be fired two seconds apart.
1183 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49227328"></a>7.12. Pad Orientation</h3></div></div></div><p>
1184 TeleMetrum, TeleMega and EasyMega measure acceleration along the axis
1185 of the board. Which way the board is oriented affects the
1186 sign of the acceleration value. Instead of trying to guess
1187 which way the board is mounted in the air frame, the
1188 altimeter must be explicitly configured for either Antenna
1189 Up or Antenna Down. The default, Antenna Up, expects the end
1190 of the board connected to the 70cm antenna to be nearest the
1191 nose of the rocket, with the end containing the screw
1192 terminals nearest the tail.
1193 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49229568"></a>7.13. Configurable Pyro Channels</h3></div></div></div><p>
1194 In addition to the usual Apogee and Main pyro channels,
1195 TeleMega and EasyMega have four additional channels that can be configured
1196 to activate when various flight conditions are
1197 satisfied. You can select as many conditions as necessary;
1198 all of them must be met in order to activate the
1199 channel. The conditions available are:
1200 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
1201 Acceleration away from the ground. Select a value, and
1202 then choose whether acceleration should be above or
1203 below that value. Acceleration is positive upwards, so
1204 accelerating towards the ground would produce negative
1205 numbers. Acceleration during descent is noisy and
1206 inaccurate, so be careful when using it during these
1207 phases of the flight.
1208 </p></li><li class="listitem"><p>
1209 Vertical speed. Select a value, and then choose whether
1210 vertical speed should be above or below that
1211 value. Speed is positive upwards, so moving towards the
1212 ground would produce negative numbers. Speed during
1213 descent is a bit noisy and so be careful when using it
1214 during these phases of the flight.
1215 </p></li><li class="listitem"><p>
1216 Height. Select a value, and then choose whether the
1217 height above the launch pad should be above or below
1219 </p></li><li class="listitem"><p>
1220 Orientation. TeleMega and EasyMega contain a 3-axis gyroscope and
1221 accelerometer which is used to measure the current
1222 angle. Note that this angle is not the change in angle
1223 from the launch pad, but rather absolute relative to
1224 gravity; the 3-axis accelerometer is used to compute the
1225 angle of the rocket on the launch pad and initialize the
1226 system. Because this value is computed by integrating
1227 rate gyros, it gets progressively less accurate as the
1228 flight goes on. It should have an accumulated error of
1229 less than 0.2°/second (after 10 seconds of flight, the
1230 error should be less than 2°).
1232 The usual use of the orientation configuration is to
1233 ensure that the rocket is traveling mostly upwards when
1234 deciding whether to ignite air starts or additional
1235 stages. For that, choose a reasonable maximum angle
1236 (like 20°) and set the motor igniter to require an angle
1237 of less than that value.
1238 </p></li><li class="listitem"><p>
1239 Flight Time. Time since boost was detected. Select a
1240 value and choose whether to activate the pyro channel
1241 before or after that amount of time.
1242 </p></li><li class="listitem"><p>
1243 Ascending. A simple test saying whether the rocket is
1244 going up or not. This is exactly equivalent to testing
1245 whether the speed is > 0.
1246 </p></li><li class="listitem"><p>
1247 Descending. A simple test saying whether the rocket is
1248 going down or not. This is exactly equivalent to testing
1249 whether the speed is < 0.
1250 </p></li><li class="listitem"><p>
1251 After Motor. The flight software counts each time the
1252 rocket starts accelerating (presumably due to a motor or
1253 motors igniting). Use this value to count ignitions for
1254 multi-staged or multi-airstart launches.
1255 </p></li><li class="listitem"><p>
1256 Delay. This value doesn't perform any checks, instead it
1257 inserts a delay between the time when the other
1258 parameters become true and when the pyro channel is
1260 </p></li><li class="listitem"><p>
1261 Flight State. The flight software tracks the flight
1262 through a sequence of states:
1263 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1264 Boost. The motor has lit and the rocket is
1265 accelerating upwards.
1266 </p></li><li class="listitem"><p>
1267 Fast. The motor has burned out and the rocket is
1268 decelerating, but it is going faster than 200m/s.
1269 </p></li><li class="listitem"><p>
1270 Coast. The rocket is still moving upwards and
1271 decelerating, but the speed is less than 200m/s.
1272 </p></li><li class="listitem"><p>
1273 Drogue. The rocket has reached apogee and is heading
1274 back down, but is above the configured Main
1276 </p></li><li class="listitem"><p>
1277 Main. The rocket is still descending, and is below
1279 </p></li><li class="listitem"><p>
1280 Landed. The rocket is no longer moving.
1281 </p></li></ol></div><p>
1283 You can select a state to limit when the pyro channel
1284 may activate; note that the check is based on when the
1285 rocket transitions <span class="emphasis"><em>into</em></span> the state, and so checking for
1286 “greater than Boost” means that the rocket is currently
1287 in boost or some later state.
1289 When a motor burns out, the rocket enters either Fast or
1290 Coast state (depending on how fast it is moving). If the
1291 computer detects upwards acceleration again, it will
1292 move back to Boost state.
1293 </p></li></ul></div></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49252176"></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="#idp49255792">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49268512">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp49284800">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp49290256">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp49297120">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp49303552">1.5. Table</a></span></dt><dt><span class="section"><a href="#idp49307136">1.6. Site Map</a></span></dt><dt><span class="section"><a href="#idp49313856">1.7. Ignitor</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49317632">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp49321584">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp49323616">4. Graph Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49326000">4.1. Flight Graph</a></span></dt><dt><span class="section"><a href="#idp49330448">4.2. Configure Graph</a></span></dt><dt><span class="section"><a href="#idp49334112">4.3. Flight Statistics</a></span></dt><dt><span class="section"><a href="#idp49337632">4.4. Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49341488">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49343056">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp49345408">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49346896">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49359200">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp49360768">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp49362384">6.3. Apogee Lockoug</a></span></dt><dt><span class="section"><a href="#idp49364112">6.4. Frequency</a></span></dt><dt><span class="section"><a href="#idp49365616">6.5. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp49367264">6.6. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp49368560">6.7. Telemetry baud rate</a></span></dt><dt><span class="section"><a href="#idp49370128">6.8. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp49371696">6.9. APRS SSID</a></span></dt><dt><span class="section"><a href="#idp49373024">6.10. Callsign</a></span></dt><dt><span class="section"><a href="#idp49374336">6.11. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp49375776">6.12. Ignitor Firing Mode</a></span></dt><dt><span class="section"><a href="#idp49382688">6.13. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp49387920">6.14. Beeper Frequency</a></span></dt><dt><span class="section"><a href="#idp49389376">6.15. Configure Pyro Channels</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49395760">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49399264">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp49404288">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp49406288">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp49408528">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp49410032">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp49411312">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp49412816">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49414448">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49425568">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp49427136">8.2. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp49428656">8.3. Telemetry Rate</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49430128">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp49431776">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp49437408">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp49441632">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp49455600">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>
1294 The AltosUI program provides a graphical user interface for
1295 interacting with the Altus Metrum product family. AltosUI can
1296 monitor telemetry data, configure devices and many other
1297 tasks. The primary interface window provides a selection of
1298 buttons, one for each major activity in the system. This chapter
1299 is split into sections, each of which documents one of the tasks
1300 provided from the top-level toolbar.
1301 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49255792"></a>1. Monitor Flight</h2></div><div><h3 class="subtitle">Receive, Record and Display Telemetry Data</h3></div></div></div><p>
1302 Selecting this item brings up a dialog box listing all of the
1303 connected TeleDongle devices. When you choose one of these,
1304 AltosUI will create a window to display telemetry data as
1305 received by the selected TeleDongle device.
1306 </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>
1307 All telemetry data received are automatically recorded in
1308 suitable log files. The name of the files includes the current
1309 date and rocket serial and flight numbers.
1311 The radio frequency being monitored by the TeleDongle device is
1312 displayed at the top of the window. You can configure the
1313 frequency by clicking on the frequency box and selecting the desired
1314 frequency. AltosUI remembers the last frequency selected for each
1315 TeleDongle and selects that automatically the next time you use
1318 Below the TeleDongle frequency selector, the window contains a few
1319 significant pieces of information about the altimeter providing
1320 the telemetry data stream:
1321 </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
1323 </p></li><li class="listitem"><p>
1324 The rocket flight state. Each flight passes through several
1325 states including Pad, Boost, Fast, Coast, Drogue, Main and
1327 </p></li><li class="listitem"><p>
1328 The Received Signal Strength Indicator value. This lets
1329 you know how strong a signal TeleDongle is receiving. The
1330 radio inside TeleDongle operates down to about -99dBm;
1331 weaker signals may not be receivable. The packet link uses
1332 error detection and correction techniques which prevent
1333 incorrect data from being reported.
1334 </p></li><li class="listitem"><p>
1335 The age of the displayed data, in seconds since the last
1336 successfully received telemetry packet. In normal operation
1337 this will stay in the low single digits. If the number starts
1338 counting up, then you are no longer receiving data over the radio
1339 link from the flight computer.
1340 </p></li></ul></div><p>
1341 Finally, the largest portion of the window contains a set of
1342 tabs, each of which contain some information about the rocket.
1343 They're arranged in 'flight order' so that as the flight
1344 progresses, the selected tab automatically switches to display
1345 data relevant to the current state of the flight. You can select
1346 other tabs at any time. The final 'table' tab displays all of
1347 the raw telemetry values in one place in a spreadsheet-like format.
1348 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49268512"></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>
1349 The 'Launch Pad' tab shows information used to decide when the
1350 rocket is ready for flight. The first elements include red/green
1351 indicators, if any of these is red, you'll want to evaluate
1352 whether the rocket is ready to launch:
1353 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Battery Voltage</span></dt><dd><p>
1354 This indicates whether the Li-Po battery powering the
1355 flight computer has sufficient charge to last for
1356 the duration of the flight. A value of more than
1357 3.8V is required for a 'GO' status.
1358 </p></dd><dt><span class="term">Apogee Igniter Voltage</span></dt><dd><p>
1359 This indicates whether the apogee
1360 igniter has continuity. If the igniter has a low
1361 resistance, then the voltage measured here will be close
1362 to the Li-Po battery voltage. A value greater than 3.2V is
1363 required for a 'GO' status.
1364 </p></dd><dt><span class="term">Main Igniter Voltage</span></dt><dd><p>
1365 This indicates whether the main
1366 igniter has continuity. If the igniter has a low
1367 resistance, then the voltage measured here will be close
1368 to the Li-Po battery voltage. A value greater than 3.2V is
1369 required for a 'GO' status.
1370 </p></dd><dt><span class="term">On-board Data Logging</span></dt><dd><p>
1371 This indicates whether there is
1372 space remaining on-board to store flight data for the
1373 upcoming flight. If you've downloaded data, but failed
1374 to erase flights, there may not be any space
1375 left. Most of our flight computers can store multiple
1376 flights, depending on the configured maximum flight log
1377 size. TeleMini v1.0 stores only a single flight, so it
1379 downloaded and erased after each flight to capture
1380 data. This only affects on-board flight logging; the
1381 altimeter will still transmit telemetry and fire
1382 ejection charges at the proper times even if the flight
1383 data storage is full.
1384 </p></dd><dt><span class="term">GPS Locked</span></dt><dd><p>
1385 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
1386 currently able to compute position information. GPS requires
1387 at least 4 satellites to compute an accurate position.
1388 </p></dd><dt><span class="term">GPS Ready</span></dt><dd><p>
1389 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
1390 10 consecutive positions without losing lock. This ensures
1391 that the GPS receiver has reliable reception from the
1393 </p></dd></dl></div><p>
1395 The Launchpad tab also shows the computed launch pad position
1396 and altitude, averaging many reported positions to improve the
1397 accuracy of the fix.
1398 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49284800"></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>
1399 This tab is shown during Boost, Fast and Coast
1400 phases. The information displayed here helps monitor the
1401 rocket as it heads towards apogee.
1403 The height, speed, acceleration and tilt are shown along
1404 with the maximum values for each of them. This allows you to
1405 quickly answer the most commonly asked questions you'll hear
1408 The current latitude and longitude reported by the GPS are
1409 also shown. Note that under high acceleration, these values
1410 may not get updated as the GPS receiver loses position
1411 fix. Once the rocket starts coasting, the receiver should
1412 start reporting position again.
1414 Finally, the current igniter voltages are reported as in the
1415 Launch Pad tab. This can help diagnose deployment failures
1416 caused by wiring which comes loose under high acceleration.
1417 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49290256"></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>
1418 Once the rocket has reached apogee and (we hope) activated the
1419 apogee charge, attention switches to tracking the rocket on
1420 the way back to the ground, and for dual-deploy flights,
1421 waiting for the main charge to fire.
1423 To monitor whether the apogee charge operated correctly, the
1424 current descent rate is reported along with the current
1425 height. Good descent rates vary based on the choice of recovery
1426 components, but generally range from 15-30m/s on drogue and should
1427 be below 10m/s when under the main parachute in a dual-deploy flight.
1429 With GPS-equipped flight computers, you can locate the rocket in the
1430 sky using the elevation and bearing information to figure
1431 out where to look. Elevation is in degrees above the
1432 horizon. Bearing is reported in degrees relative to true
1433 north. Range can help figure out how big the rocket will
1434 appear. Ground Distance shows how far it is to a point
1435 directly under the rocket and can help figure out where the
1436 rocket is likely to land. Note that all of these values are
1437 relative to the pad location. If the elevation is near 90°,
1438 the rocket is over the pad, not over you.
1440 Finally, the igniter voltages are reported in this tab as
1441 well, both to monitor the main charge as well as to see what
1442 the status of the apogee charge is. Note that some commercial
1443 e-matches are designed to retain continuity even after being
1444 fired, and will continue to show as green or return from red to
1446 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49297120"></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>
1447 Once the rocket is on the ground, attention switches to
1448 recovery. While the radio signal is often lost once the
1449 rocket is on the ground, the last reported GPS position is
1450 generally within a short distance of the actual landing location.
1452 The last reported GPS position is reported both by
1453 latitude and longitude as well as a bearing and distance from
1454 the launch pad. The distance should give you a good idea of
1455 whether to walk or hitch a ride. Take the reported
1456 latitude and longitude and enter them into your hand-held GPS
1457 unit and have that compute a track to the landing location.
1459 Our flight computers will continue to transmit RDF
1460 tones after landing, allowing you to locate the rocket by
1461 following the radio signal if necessary. You may need to get
1462 away from the clutter of the flight line, or even get up on
1463 a hill (or your neighbor's RV roof) to receive the RDF signal.
1465 The maximum height, speed and acceleration reported
1466 during the flight are displayed for your admiring observers.
1467 The accuracy of these immediate values depends on the quality
1468 of your radio link and how many packets were received.
1469 Recovering the on-board data after flight may yield
1470 more precise results.
1472 To get more detailed information about the flight, you can
1473 click on the 'Graph Flight' button which will bring up a
1474 graph window for the current flight.
1475 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49303552"></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>
1476 The table view shows all of the data available from the
1477 flight computer. Probably the most useful data on
1478 this tab is the detailed GPS information, which includes
1479 horizontal dilution of precision information, and
1480 information about the signal being received from the satellites.
1481 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49307136"></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>
1482 When the TeleMetrum has a GPS fix, the Site Map tab will map
1483 the rocket's position to make it easier for you to locate the
1484 rocket, both while it is in the air, and when it has landed. The
1485 rocket's state is indicated by color: white for pad, red for
1486 boost, pink for fast, yellow for coast, light blue for drogue,
1487 dark blue for main, and black for landed.
1489 The map's default scale is approximately 3m (10ft) per pixel. The map
1490 can be dragged using the left mouse button. The map will attempt
1491 to keep the rocket roughly centered while data is being received.
1493 You can adjust the style of map and the zoom level with
1494 buttons on the right side of the map window. You can draw a
1495 line on the map by moving the mouse over the map with a
1496 button other than the left one pressed, or by pressing the
1497 left button while also holding down the shift key. The
1498 length of the line in real-world units will be shown at the
1501 Images are fetched automatically via the Google Maps Static API,
1502 and cached on disk for reuse. If map images cannot be downloaded,
1503 the rocket's path will be traced on a dark gray background
1506 You can pre-load images for your favorite launch sites
1507 before you leave home; check out the 'Preload Maps' section below.
1508 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49313856"></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>
1509 TeleMega includes four additional programmable pyro
1510 channels. The Ignitor tab shows whether each of them has
1511 continuity. If an ignitor has a low resistance, then the
1512 voltage measured here will be close to the pyro battery
1513 voltage. A value greater than 3.2V is required for a 'GO'
1515 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49317632"></a>2. Save Flight Data</h2></div></div></div><p>
1516 The altimeter records flight data to its internal flash memory.
1517 TeleMetrum data is recorded at a much higher rate than the telemetry
1518 system can handle, and is not subject to radio drop-outs. As
1519 such, it provides a more complete and precise record of the
1520 flight. The 'Save Flight Data' button allows you to read the
1521 flash memory and write it to disk.
1523 Clicking on the 'Save Flight Data' button brings up a list of
1524 connected flight computers and TeleDongle devices. If you select a
1525 flight computer, the flight data will be downloaded from that
1526 device directly. If you select a TeleDongle device, flight data
1527 will be downloaded from a flight computer over radio link via the
1528 specified TeleDongle. See the chapter on Controlling An Altimeter
1529 Over The Radio Link for more information.
1531 After the device has been selected, a dialog showing the
1532 flight data saved in the device will be shown allowing you to
1533 select which flights to download and which to delete. With
1534 version 0.9 or newer firmware, you must erase flights in order
1535 for the space they consume to be reused by another
1536 flight. This prevents accidentally losing flight data
1537 if you neglect to download data before flying again. Note that
1538 if there is no more space available in the device, then no
1539 data will be recorded during the next flight.
1541 The file name for each flight log is computed automatically
1542 from the recorded flight date, altimeter serial number and
1543 flight number information.
1544 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49321584"></a>3. Replay Flight</h2></div></div></div><p>
1545 Select this button and you are prompted to select a flight
1546 record file, either a .telem file recording telemetry data or a
1547 .eeprom file containing flight data saved from the altimeter
1550 Once a flight record is selected, the flight monitor interface
1551 is displayed and the flight is re-enacted in real time. Check
1552 the Monitor Flight chapter above to learn how this window operates.
1553 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49323616"></a>4. Graph Data</h2></div></div></div><p>
1554 Select this button and you are prompted to select a flight
1555 record file, either a .telem file recording telemetry data or a
1556 .eeprom file containing flight data saved from
1559 Note that telemetry files will generally produce poor graphs
1560 due to the lower sampling rate and missed telemetry packets.
1561 Use saved flight data in .eeprom files for graphing where possible.
1563 Once a flight record is selected, a window with multiple tabs is
1565 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49326000"></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>
1566 By default, the graph contains acceleration (blue),
1567 velocity (green) and altitude (red).
1569 The graph can be zoomed into a particular area by clicking and
1570 dragging down and to the right. Once zoomed, the graph can be
1571 reset by clicking and dragging up and to the left. Holding down
1572 control and clicking and dragging allows the graph to be panned.
1573 The right mouse button causes a pop-up menu to be displayed, giving
1574 you the option save or print the plot.
1575 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49330448"></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>
1576 This selects which graph elements to show, and, at the
1577 very bottom, lets you switch between metric and
1579 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49334112"></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>
1580 Shows overall data computed from the flight.
1581 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49337632"></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>
1582 Shows a satellite image of the flight area overlaid
1583 with the path of the flight. The red concentric
1584 circles mark the launch pad, the black concentric
1585 circles mark the landing location.
1586 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49341488"></a>5. Export Data</h2></div></div></div><p>
1587 This tool takes the raw data files and makes them available for
1588 external analysis. When you select this button, you are prompted to
1589 select a flight data file, which can be either a .eeprom or .telem.
1590 The .eeprom files contain higher resolution and more continuous data,
1591 while .telem files contain receiver signal strength information.
1592 Next, a second dialog appears which is used to select
1593 where to write the resulting file. It has a selector to choose
1594 between CSV and KML file formats.
1595 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49343056"></a>5.1. Comma Separated Value Format</h3></div></div></div><p>
1596 This is a text file containing the data in a form suitable for
1597 import into a spreadsheet or other external data analysis
1598 tool. The first few lines of the file contain the version and
1599 configuration information from the altimeter, then
1600 there is a single header line which labels all of the
1601 fields. All of these lines start with a '#' character which
1602 many tools can be configured to skip over.
1604 The remaining lines of the file contain the data, with each
1605 field separated by a comma and at least one space. All of
1606 the sensor values are converted to standard units, with the
1607 barometric data reported in both pressure, altitude and
1608 height above pad units.
1609 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49345408"></a>5.2. Keyhole Markup Language (for Google Earth)</h3></div></div></div><p>
1610 This is the format used by Google Earth to provide an overlay
1611 within that application. With this, you can use Google Earth to
1612 see the whole flight path in 3D.
1613 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49346896"></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>
1614 Select this button and then select either an altimeter or
1615 TeleDongle Device from the list provided. Selecting a TeleDongle
1616 device will use the radio link to configure a remote altimeter.
1618 The first few lines of the dialog provide information about the
1619 connected device, including the product name,
1620 software version and hardware serial number. Below that are the
1621 individual configuration entries.
1623 At the bottom of the dialog, there are four buttons:
1624 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Save</span></dt><dd><p>
1625 This writes any changes to the
1626 configuration parameter block in flash memory. If you don't
1627 press this button, any changes you make will be lost.
1628 </p></dd><dt><span class="term">Reset</span></dt><dd><p>
1629 This resets the dialog to the most recently saved values,
1630 erasing any changes you have made.
1631 </p></dd><dt><span class="term">Reboot</span></dt><dd><p>
1632 This reboots the device. Use this to
1633 switch from idle to pad mode by rebooting once the rocket is
1634 oriented for flight, or to confirm changes you think you saved
1636 </p></dd><dt><span class="term">Close</span></dt><dd><p>
1637 This closes the dialog. Any unsaved changes will be
1639 </p></dd></dl></div><p>
1640 The rest of the dialog contains the parameters to be configured.
1641 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49359200"></a>6.1. Main Deploy Altitude</h3></div></div></div><p>
1642 This sets the altitude (above the recorded pad altitude) at
1643 which the 'main' igniter will fire. The drop-down menu shows
1644 some common values, but you can edit the text directly and
1645 choose whatever you like. If the apogee charge fires below
1646 this altitude, then the main charge will fire two seconds
1647 after the apogee charge fires.
1648 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49360768"></a>6.2. Apogee Delay</h3></div></div></div><p>
1649 When flying redundant electronics, it's often important to
1650 ensure that multiple apogee charges don't fire at precisely
1651 the same time, as that can over pressurize the apogee deployment
1652 bay and cause a structural failure of the air-frame. The Apogee
1653 Delay parameter tells the flight computer to fire the apogee
1654 charge a certain number of seconds after apogee has been
1656 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49362384"></a>6.3. Apogee Lockoug</h3></div></div></div><p>
1657 Apogee lockout is the number of seconds after boost where
1658 the flight computer will not fire the apogee charge, even if
1659 the rocket appears to be at apogee. This is often called
1660 'Mach Delay', as it is intended to prevent a flight computer
1661 from unintentionally firing apogee charges due to the pressure
1662 spike that occurrs across a mach transition. Altus Metrum
1663 flight computers include a Kalman filter which is not fooled
1664 by this sharp pressure increase, and so this setting should
1665 be left at the default value of zero to disable it.
1666 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49364112"></a>6.4. Frequency</h3></div></div></div><p>
1667 This configures which of the frequencies to use for both
1668 telemetry and packet command mode. Note that if you set this
1669 value via packet command mode, the TeleDongle frequency will
1670 also be automatically reconfigured to match so that
1671 communication will continue afterwards.
1672 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49365616"></a>6.5. RF Calibration</h3></div></div></div><p>
1673 The radios in every Altus Metrum device are calibrated at the
1674 factory to ensure that they transmit and receive on the
1675 specified frequency. If you need to you can adjust the calibration
1676 by changing this value. Do not do this without understanding what
1677 the value means, read the appendix on calibration and/or the source
1678 code for more information. To change a TeleDongle's calibration,
1679 you must reprogram the unit completely.
1680 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49367264"></a>6.6. Telemetry/RDF/APRS Enable</h3></div></div></div><p>
1681 Enables the radio for transmission during flight. When
1682 disabled, the radio will not transmit anything during flight
1684 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49368560"></a>6.7. Telemetry baud rate</h3></div></div></div><p>
1685 This sets the modulation bit rate for data transmission for
1686 both telemetry and packet link mode. Lower bit
1687 rates will increase range while reducing the amount of data
1688 that can be sent and increasing battery consumption. All
1689 telemetry is done using a rate 1/2 constraint 4 convolution
1690 code, so the actual data transmission rate is 1/2 of the
1691 modulation bit rate specified here.
1692 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49370128"></a>6.8. APRS Interval</h3></div></div></div><p>
1693 How often to transmit GPS information via APRS (in
1694 seconds). When set to zero, APRS transmission is
1695 disabled. This option is available on TeleMetrum v2 and
1696 TeleMega boards. TeleMetrum v1 boards cannot transmit APRS
1697 packets. Note that a single APRS packet takes nearly a full
1698 second to transmit, so enabling this option will prevent
1699 sending any other telemetry during that time.
1700 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49371696"></a>6.9. APRS SSID</h3></div></div></div><p>
1701 Which SSID to report in APRS packets. By default, this is
1702 set to the last digit of the serial number, but can be
1703 configured to any value from 0 to 9.
1704 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49373024"></a>6.10. Callsign</h3></div></div></div><p>
1705 This sets the call sign included in each telemetry packet. Set this
1706 as needed to conform to your local radio regulations.
1707 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49374336"></a>6.11. Maximum Flight Log Size</h3></div></div></div><p>
1708 This sets the space (in kilobytes) allocated for each flight
1709 log. The available space will be divided into chunks of this
1710 size. A smaller value will allow more flights to be stored,
1711 a larger value will record data from longer flights.
1712 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49375776"></a>6.12. Ignitor Firing Mode</h3></div></div></div><p>
1713 This configuration parameter allows the two standard ignitor
1714 channels (Apogee and Main) to be used in different
1716 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Dual Deploy</span></dt><dd><p>
1717 This is the usual mode of operation; the
1718 'apogee' channel is fired at apogee and the 'main'
1719 channel at the height above ground specified by the
1720 'Main Deploy Altitude' during descent.
1721 </p></dd><dt><span class="term">Redundant Apogee</span></dt><dd><p>
1722 This fires both channels at
1723 apogee, the 'apogee' channel first followed after a two second
1724 delay by the 'main' channel.
1725 </p></dd><dt><span class="term">Redundant Main</span></dt><dd><p>
1726 This fires both channels at the
1727 height above ground specified by the Main Deploy
1728 Altitude setting during descent. The 'apogee'
1729 channel is fired first, followed after a two second
1730 delay by the 'main' channel.
1731 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49382688"></a>6.13. Pad Orientation</h3></div></div></div><p>
1732 Because they include accelerometers, TeleMetrum,
1733 TeleMega and EasyMega are sensitive to the orientation of the board. By
1734 default, they expect the antenna end to point forward. This
1735 parameter allows that default to be changed, permitting the
1736 board to be mounted with the antenna pointing aft instead.
1737 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Antenna Up</span></dt><dd><p>
1738 In this mode, the antenna end of the
1739 flight computer must point forward, in line with the
1740 expected flight path.
1741 </p></dd><dt><span class="term">Antenna Down</span></dt><dd><p>
1742 In this mode, the antenna end of the
1743 flight computer must point aft, in line with the
1744 expected flight path.
1745 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49387920"></a>6.14. Beeper Frequency</h3></div></div></div><p>
1746 The beeper on all Altus Metrum flight computers works best
1747 at 4000Hz, however if you have more than one flight computer
1748 in a single airframe, having all of them sound at the same
1749 frequency can be confusing. This parameter lets you adjust
1750 the base beeper frequency value.
1751 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49389376"></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>
1752 This opens a separate window to configure the additional
1753 pyro channels available on TeleMega and EasyMega. One column is
1754 presented for each channel. Each row represents a single
1755 parameter, if enabled the parameter must meet the specified
1756 test for the pyro channel to be fired. See the Pyro Channels
1757 section in the System Operation chapter above for a
1758 description of these parameters.
1760 Select conditions and set the related value; the pyro
1761 channel will be activated when <span class="emphasis"><em>all</em></span> of the
1762 conditions are met. Each pyro channel has a separate set of
1763 configuration values, so you can use different values for
1764 the same condition with different channels.
1766 At the bottom of the window, the 'Pyro Firing Time'
1767 configuration sets the length of time (in seconds) which
1768 each of these pyro channels will fire for.
1770 Once you have selected the appropriate configuration for all
1771 of the necessary pyro channels, you can save the pyro
1772 configuration along with the rest of the flight computer
1773 configuration by pressing the 'Save' button in the main
1774 Configure Flight Computer window.
1775 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49395760"></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>
1776 This button presents a dialog so that you can configure the AltosUI global settings.
1777 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49399264"></a>7.1. Voice Settings</h3></div></div></div><p>
1778 AltosUI provides voice announcements during flight so that you
1779 can keep your eyes on the sky and still get information about
1780 the current flight status. However, sometimes you don't want
1782 </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>
1783 Plays a short message allowing you to verify
1784 that the audio system is working and the volume settings
1786 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49404288"></a>7.2. Log Directory</h3></div></div></div><p>
1787 AltosUI logs all telemetry data and saves all TeleMetrum flash
1788 data to this directory. This directory is also used as the
1789 staring point when selecting data files for display or export.
1791 Click on the directory name to bring up a directory choosing
1792 dialog, select a new directory and click 'Select Directory' to
1793 change where AltosUI reads and writes data files.
1794 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49406288"></a>7.3. Callsign</h3></div></div></div><p>
1795 This value is transmitted in each command packet sent from
1796 TeleDongle and received from an altimeter. It is not used in
1797 telemetry mode, as the callsign configured in the altimeter board
1798 is included in all telemetry packets. Configure this
1799 with the AltosUI operators call sign as needed to comply with
1800 your local radio regulations.
1802 Note that to successfully command a flight computer over the radio
1803 (to configure the altimeter, monitor idle, or fire pyro charges),
1804 the callsign configured here must exactly match the callsign
1805 configured in the flight computer. This matching is case
1807 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49408528"></a>7.4. Imperial Units</h3></div></div></div><p>
1808 This switches between metric units (meters) and imperial
1809 units (feet and miles). This affects the display of values
1810 use during flight monitoring, configuration, data graphing
1811 and all of the voice announcements. It does not change the
1812 units used when exporting to CSV files, those are always
1813 produced in metric units.
1814 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49410032"></a>7.5. Font Size</h3></div></div></div><p>
1815 Selects the set of fonts used in the flight monitor
1816 window. Choose between the small, medium and large sets.
1817 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49411312"></a>7.6. Serial Debug</h3></div></div></div><p>
1818 This causes all communication with a connected device to be
1819 dumped to the console from which AltosUI was started. If
1820 you've started it from an icon or menu entry, the output
1821 will simply be discarded. This mode can be useful to debug
1822 various serial communication issues.
1823 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49412816"></a>7.7. Manage Frequencies</h3></div></div></div><p>
1824 This brings up a dialog where you can configure the set of
1825 frequencies shown in the various frequency menus. You can
1826 add as many as you like, or even reconfigure the default
1827 set. Changing this list does not affect the frequency
1828 settings of any devices, it only changes the set of
1829 frequencies shown in the menus.
1830 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49414448"></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>
1831 Select this button and then select a TeleDongle or TeleBT Device from the list provided.
1833 The first few lines of the dialog provide information about the
1834 connected device, including the product name,
1835 software version and hardware serial number. Below that are the
1836 individual configuration entries.
1838 Note that TeleDongle and TeleBT don't save any configuration
1839 data, the settings here are recorded on the local machine in
1840 the Java preferences database. Moving the device to
1841 another machine, or using a different user account on the same
1842 machine will cause settings made here to have no effect.
1844 At the bottom of the dialog, there are three buttons:
1845 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Save</span></dt><dd><p>
1846 This writes any changes to the
1847 local Java preferences file. If you don't
1848 press this button, any changes you make will be lost.
1849 </p></dd><dt><span class="term">Reset</span></dt><dd><p>
1850 This resets the dialog to the most recently saved values,
1851 erasing any changes you have made.
1852 </p></dd><dt><span class="term">Close</span></dt><dd><p>
1853 This closes the dialog. Any unsaved changes will be
1855 </p></dd></dl></div><p>
1856 The rest of the dialog contains the parameters to be configured.
1857 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49425568"></a>8.1. Frequency</h3></div></div></div><p>
1858 This configures the frequency to use for both telemetry and
1859 packet command mode. Set this before starting any operation
1860 involving packet command mode so that it will use the right
1861 frequency. Telemetry monitoring mode also provides a menu to
1862 change the frequency, and that menu also sets the same Java
1863 preference value used here.
1864 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49427136"></a>8.2. RF Calibration</h3></div></div></div><p>
1865 The radios in every Altus Metrum device are calibrated at the
1866 factory to ensure that they transmit and receive on the
1867 specified frequency. To change a TeleDongle or TeleBT's calibration,
1868 you must reprogram the unit completely, so this entry simply
1869 shows the current value and doesn't allow any changes.
1870 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49428656"></a>8.3. Telemetry Rate</h3></div></div></div><p>
1871 This lets you match the telemetry and packet link rate from
1872 the transmitter. If they don't match, the device won't
1874 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49430128"></a>9. Flash Image</h2></div></div></div><p>
1875 This reprograms Altus Metrum devices with new
1876 firmware. TeleMetrum v1.x, TeleDongle, TeleMini and TeleBT are
1877 all reprogrammed by using another similar unit as a
1878 programming dongle (pair programming). TeleMega, EasyMega, TeleMetrum v2
1879 and EasyMini are all programmed directly over their USB ports
1880 (self programming). Please read the directions for flashing
1881 devices in the Updating Device Firmware chapter below.
1882 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49431776"></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>
1883 This activates the igniter circuits in the flight computer to help
1884 test recovery systems deployment. Because this command can operate
1885 over the Packet Command Link, you can prepare the rocket as
1886 for flight and then test the recovery system without needing
1887 to snake wires inside the air-frame.
1889 Selecting the 'Fire Igniter' button brings up the usual device
1890 selection dialog. Pick the desired device. This brings up another
1891 window which shows the current continuity test status for all
1892 of the pyro channels.
1894 Next, select the desired igniter to fire. This will enable the
1897 Select the 'Arm' button. This enables the 'Fire' button. The
1898 word 'Arm' is replaced by a countdown timer indicating that
1899 you have 10 seconds to press the 'Fire' button or the system
1900 will deactivate, at which point you start over again at
1901 selecting the desired igniter.
1902 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49437408"></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>
1903 This listens for telemetry packets on all of the configured
1904 frequencies, displaying information about each device it
1905 receives a packet from. You can select which of the baud rates
1906 and telemetry formats should be tried; by default, it only listens
1907 at 38400 baud with the standard telemetry format used in v1.0 and later
1909 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49441632"></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>
1910 Before heading out to a new launch site, you can use this to
1911 load satellite images in case you don't have internet
1912 connectivity at the site. This loads a fairly large area
1913 around the launch site, which should cover any flight you're likely to make.
1915 There's a drop-down menu of launch sites we know about; if
1916 your favorites aren't there, please let us know the lat/lon
1917 and name of the site. The contents of this list are actually
1918 downloaded from our server at run-time, so as new sites are sent
1919 in, they'll get automatically added to this list.
1920 If the launch site isn't in the list, you can manually enter the lat/lon values
1922 There are four different kinds of maps you can view; you can
1923 select which to download by selecting as many as you like from
1924 the available types:
1925 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Hybrid</span></dt><dd><p>
1926 A combination of satellite imagery and road data. This
1927 is the default view.
1928 </p></dd><dt><span class="term">Satellite</span></dt><dd><p>
1929 Just the satellite imagery without any annotation.
1930 </p></dd><dt><span class="term">Roadmap</span></dt><dd><p>
1931 Roads, political boundaries and a few geographic features.
1932 </p></dd><dt><span class="term">Terrain</span></dt><dd><p>
1933 Contour intervals and shading that show hills and
1935 </p></dd></dl></div><p>
1937 You can specify the range of zoom levels to download; smaller
1938 numbers show more area with less resolution. The default
1939 level, 0, shows about 3m/pixel. One zoom level change
1940 doubles or halves that number.
1942 The Tile Radius value sets how large an area around the center
1943 point to download. Each tile is 512x512 pixels, and the
1944 'radius' value specifies how many tiles away from the center
1945 will be downloaded. Specify a radius of 0 and you get only the
1946 center tile. A radius of 1 loads a 3x3 grid, centered on the
1949 Clicking the 'Load Map' button will fetch images from Google
1950 Maps; note that Google limits how many images you can fetch at
1951 once, so if you load more than one launch site, you may get
1952 some gray areas in the map which indicate that Google is tired
1953 of sending data to you. Try again later.
1954 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49455600"></a>13. Monitor Idle</h2></div></div></div><p>
1955 This brings up a dialog similar to the Monitor Flight UI,
1956 except it works with the altimeter in “idle” mode by sending
1957 query commands to discover the current state rather than
1958 listening for telemetry packets. Because this uses command
1959 mode, it needs to have the TeleDongle and flight computer
1960 callsigns match exactly. If you can receive telemetry, but
1961 cannot manage to run Monitor Idle, then it's very likely that
1962 your callsigns are different in some way.
1963 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49457696"></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="#idp49460080">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp49462016">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp49464016">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp49465472">4. AltosDroid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp49466784">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49480336">5. Downloading Flight Logs</a></span></dt></dl></div><p>
1964 AltosDroid provides the same flight monitoring capabilities as
1965 AltosUI, but runs on Android devices and is designed to connect
1966 to a TeleBT receiver over Bluetooth™. AltosDroid monitors
1967 telemetry data, logging it to internal storage in the Android
1968 device, and presents that data in a UI the same way the 'Monitor
1969 Flight' window does in AltosUI.
1971 This manual will explain how to configure AltosDroid, connect
1972 to TeleBT, operate the flight monitoring interface and describe
1973 what the displayed data means.
1974 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49460080"></a>1. Installing AltosDroid</h2></div></div></div><p>
1975 AltosDroid is available from the Google Play store. To install
1976 it on your Android device, open the Google Play Store
1977 application and search for “altosdroid”. Make sure you don't
1978 have a space between “altos” and “droid” or you probably won't
1979 find what you want. That should bring you to the right page
1980 from which you can download and install the application.
1981 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49462016"></a>2. Connecting to TeleBT</h2></div></div></div><p>
1982 Press the Android 'Menu' button or soft-key to see the
1983 configuration options available. Select the 'Connect a device'
1984 option and then the 'Scan for devices' entry at the bottom to
1985 look for your TeleBT device. Select your device, and when it
1986 asks for the code, enter '1234'.
1988 Subsequent connections will not require you to enter that
1989 code, and your 'paired' device will appear in the list without
1991 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49464016"></a>3. Configuring AltosDroid</h2></div></div></div><p>
1992 The only configuration option available for AltosDroid is
1993 which frequency to listen on. Press the Android 'Menu' button
1994 or soft-key and pick the 'Select radio frequency' entry. That
1995 brings up a menu of pre-set radio frequencies; pick the one
1996 which matches your altimeter.
1997 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49465472"></a>4. AltosDroid Flight Monitoring</h2></div></div></div><p>
1998 AltosDroid is designed to mimic the AltosUI flight monitoring
1999 display, providing separate tabs for each stage of your rocket
2000 flight along with a tab containing a map of the local area
2001 with icons marking the current location of the altimeter and
2003 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49466784"></a>4.1. Pad</h3></div></div></div><p>
2004 The 'Launch Pad' tab shows information used to decide when the
2005 rocket is ready for flight. The first elements include red/green
2006 indicators, if any of these is red, you'll want to evaluate
2007 whether the rocket is ready to launch:
2008 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Battery Voltage</span></dt><dd><p>
2009 This indicates whether the Li-Po battery
2010 powering the TeleMetrum has sufficient charge to last for
2011 the duration of the flight. A value of more than
2012 3.8V is required for a 'GO' status.
2013 </p></dd><dt><span class="term">Apogee Igniter Voltage</span></dt><dd><p>
2014 This indicates whether the apogee
2015 igniter has continuity. If the igniter has a low
2016 resistance, then the voltage measured here will be close
2017 to the Li-Po battery voltage. A value greater than 3.2V is
2018 required for a 'GO' status.
2019 </p></dd><dt><span class="term">Main Igniter Voltage</span></dt><dd><p>
2020 This indicates whether the main
2021 igniter has continuity. If the igniter has a low
2022 resistance, then the voltage measured here will be close
2023 to the Li-Po battery voltage. A value greater than 3.2V is
2024 required for a 'GO' status.
2025 </p></dd><dt><span class="term">On-board Data Logging</span></dt><dd><p>
2026 This indicates whether there is
2027 space remaining on-board to store flight data for the
2028 upcoming flight. If you've downloaded data, but failed
2029 to erase flights, there may not be any space
2030 left. TeleMetrum can store multiple flights, depending
2031 on the configured maximum flight log size. TeleMini
2032 stores only a single flight, so it will need to be
2033 downloaded and erased after each flight to capture
2034 data. This only affects on-board flight logging; the
2035 altimeter will still transmit telemetry and fire
2036 ejection charges at the proper times.
2037 </p></dd><dt><span class="term">GPS Locked</span></dt><dd><p>
2038 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
2039 currently able to compute position information. GPS requires
2040 at least 4 satellites to compute an accurate position.
2041 </p></dd><dt><span class="term">GPS Ready</span></dt><dd><p>
2042 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
2043 10 consecutive positions without losing lock. This ensures
2044 that the GPS receiver has reliable reception from the
2046 </p></dd></dl></div><p>
2048 The Launchpad tab also shows the computed launch pad position
2049 and altitude, averaging many reported positions to improve the
2050 accuracy of the fix.
2051 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49480336"></a>5. Downloading Flight Logs</h2></div></div></div><p>
2052 AltosDroid always saves every bit of telemetry data it
2053 receives. To download that to a computer for use with AltosUI,
2054 simply remove the SD card from your Android device, or connect
2055 your device to your computer's USB port and browse the files
2056 on that device. You will find '.telem' files in the TeleMetrum
2057 directory that will work with AltosUI directly.
2058 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49482000"></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="#idp49482640">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp49484544">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp49487072">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp49500464">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp49503008">5. Future Plans</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49482640"></a>1. Being Legal</h2></div></div></div><p>
2059 First off, in the US, you need an <a class="ulink" href="http://www.altusmetrum.org/Radio/" target="_top">amateur radio license</a> or
2060 other authorization to legally operate the radio transmitters that are part
2062 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49484544"></a>2. In the Rocket</h2></div></div></div><p>
2063 In the rocket itself, you just need a flight computer and
2064 a single-cell, 3.7 volt nominal Li-Po rechargeable battery. An
2065 850mAh battery weighs less than a 9V alkaline battery, and will
2066 run a TeleMetrum, TeleMega or EasyMega for hours.
2067 A 110mAh battery weighs less than a triple A battery and is a good
2068 choice for use with TeleMini or EasyMini.
2070 By default, we ship TeleMini, TeleMetrum and TeleMega flight computers with a simple wire antenna.
2071 If your electronics bay or the air-frame it resides within is made
2072 of carbon fiber, which is opaque to RF signals, you may prefer to
2073 install an SMA connector so that you can run a coaxial cable to an
2074 antenna mounted elsewhere in the rocket. However, note that the
2075 GPS antenna is fixed on all current products, so you really want
2076 to install the flight computer in a bay made of RF-transparent
2077 materials if at all possible.
2078 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49487072"></a>3. On the Ground</h2></div></div></div><p>
2079 To receive the data stream from the rocket, you need an antenna and short
2080 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
2081 adapter instead of feedline between the antenna feedpoint and
2082 TeleDongle, as this will give you the best performance. The
2083 TeleDongle in turn plugs directly into the USB port on a notebook
2084 computer. Because TeleDongle looks like a simple serial port, your computer
2085 does not require special device drivers... just plug it in.
2087 The GUI tool, AltosUI, is written in Java and runs across
2088 Linux, Mac OS and Windows. There's also a suite of C tools
2089 for Linux which can perform most of the same tasks.
2091 Alternatively, a TeleBT attached with an SMA to BNC adapter at the
2092 feed point of a hand-held yagi used in conjunction with an Android
2093 device running AltosDroid makes an outstanding ground station.
2095 After the flight, you can use the radio link to extract the more detailed data
2096 logged in either TeleMetrum or TeleMini devices, or you can use a mini USB cable to plug into the
2097 TeleMetrum board directly. Pulling out the data without having to open up
2098 the rocket is pretty cool! A USB cable is also how you charge the Li-Po
2099 battery, so you'll want one of those anyway... the same cable used by lots
2100 of digital cameras and other modern electronic stuff will work fine.
2102 If your rocket lands out of sight, you may enjoy having a hand-held
2103 GPS receiver, so that you can put in a way-point for the last
2104 reported rocket position before touch-down. This makes looking for
2105 your rocket a lot like Geo-Caching... just go to the way-point and
2106 look around starting from there. AltosDroid on an Android device
2107 with GPS receiver works great for this, too!
2109 You may also enjoy having a ham radio “HT” that covers the 70cm band... you
2110 can use that with your antenna to direction-find the rocket on the ground
2111 the same way you can use a Walston or Beeline tracker. This can be handy
2112 if the rocket is hiding in sage brush or a tree, or if the last GPS position
2113 doesn't get you close enough because the rocket dropped into a canyon, or
2114 the wind is blowing it across a dry lake bed, or something like that... Keith
2115 currently uses a Yaesu FT1D, Bdale has a Yaesu VX-7R, which
2116 is a nicer radio in most ways but doesn't support APRS.
2118 So, to recap, on the ground the hardware you'll need includes:
2119 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2120 an antenna and feed-line or adapter
2121 </p></li><li class="listitem"><p>
2123 </p></li><li class="listitem"><p>
2125 </p></li><li class="listitem"><p>
2126 optionally, a hand-held GPS receiver
2127 </p></li><li class="listitem"><p>
2128 optionally, an HT or receiver covering 435 MHz
2129 </p></li></ol></div><p>
2131 The best hand-held commercial directional antennas we've found for radio
2132 direction finding rockets are from
2133 <a class="ulink" href="http://www.arrowantennas.com/" target="_top">
2136 The 440-3 and 440-5 are both good choices for finding a
2137 TeleMetrum- or TeleMini- equipped rocket when used with a suitable
2138 70cm HT. TeleDongle and an SMA to BNC adapter fit perfectly
2139 between the driven element and reflector of Arrow antennas.
2140 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49500464"></a>4. Data Analysis</h2></div></div></div><p>
2141 Our software makes it easy to log the data from each flight, both the
2142 telemetry received during the flight itself, and the more
2143 complete data log recorded in the flash memory on the altimeter
2144 board. Once this data is on your computer, our post-flight tools make it
2145 easy to quickly get to the numbers everyone wants, like apogee altitude,
2146 max acceleration, and max velocity. You can also generate and view a
2147 standard set of plots showing the altitude, acceleration, and
2148 velocity of the rocket during flight. And you can even export a TeleMetrum data file
2149 usable with Google Maps and Google Earth for visualizing the flight path
2150 in two or three dimensions!
2152 Our ultimate goal is to emit a set of files for each flight that can be
2153 published as a web page per flight, or just viewed on your local disk with
2155 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49503008"></a>5. Future Plans</h2></div></div></div><p>
2156 We have designed and prototyped several “companion boards” that
2157 can attach to the companion connector on TeleMetrum,
2158 TeleMega and EasyMega
2159 flight computers to collect more data, provide more pyro channels,
2160 and so forth. We do not yet know if or when any of these boards
2161 will be produced in enough quantity to sell. If you have specific
2162 interests for data collection or control of events in your rockets
2163 beyond the capabilities of our existing productions, please let
2166 Because all of our work is open, both the hardware designs and the
2167 software, if you have some great idea for an addition to the current
2168 Altus Metrum family, feel free to dive in and help! Or let us know
2169 what you'd like to see that we aren't already working on, and maybe
2170 we'll get excited about it too...
2173 <a class="ulink" href="http://altusmetrum.org/" target="_top">web site</a> for more news
2174 and information as our family of products evolves!
2175 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49506848"></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="#idp49508304">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp49513136">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp49518704">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp49523488">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp49531056">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp49533856">6. Ground Testing</a></span></dt></dl></div><p>
2176 Building high-power rockets that fly safely is hard enough. Mix
2177 in some sophisticated electronics and a bunch of radio energy
2178 and some creativity and/or compromise may be required. This chapter
2179 contains some suggestions about how to install Altus Metrum
2180 products into a rocket air-frame, including how to safely and
2181 reliably mix a variety of electronics into the same air-frame.
2182 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49508304"></a>1. Mounting the Altimeter</h2></div></div></div><p>
2183 The first consideration is to ensure that the altimeter is
2184 securely fastened to the air-frame. For most of our products, we
2185 prefer nylon standoffs and nylon screws; they're good to at least 50G
2186 and cannot cause any electrical issues on the board. Metal screws
2187 and standoffs are fine, too, just be careful to avoid electrical
2188 shorts! For TeleMini v1.0, we usually cut small pieces of 1/16 inch
2190 under the screw holes, and then take 2x56 nylon screws and
2191 screw them through the TeleMini mounting holes, through the
2192 balsa and into the underlying material.
2193 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2194 Make sure accelerometer-equipped products like TeleMetrum,
2195 TeleMega and EasyMega are aligned precisely along the axis of
2196 acceleration so that the accelerometer can accurately
2197 capture data during the flight.
2198 </p></li><li class="listitem"><p>
2199 Watch for any metal touching components on the
2200 board. Shorting out connections on the bottom of the board
2201 can cause the altimeter to fail during flight.
2202 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49513136"></a>2. Dealing with the Antenna</h2></div></div></div><p>
2203 The antenna supplied is just a piece of solid, insulated,
2204 wire. If it gets damaged or broken, it can be easily
2205 replaced. It should be kept straight and not cut; bending or
2206 cutting it will change the resonant frequency and/or
2207 impedance, making it a less efficient radiator and thus
2208 reducing the range of the telemetry signal.
2210 Keeping metal away from the antenna will provide better range
2211 and a more even radiation pattern. In most rockets, it's not
2212 entirely possible to isolate the antenna from metal
2213 components; there are often bolts, all-thread and wires from other
2214 electronics to contend with. Just be aware that the more stuff
2215 like this around the antenna, the lower the range.
2217 Make sure the antenna is not inside a tube made or covered
2218 with conducting material. Carbon fiber is the most common
2219 culprit here -- CF is a good conductor and will effectively
2220 shield the antenna, dramatically reducing signal strength and
2221 range. Metallic flake paint is another effective shielding
2222 material which should be avoided around any antennas.
2224 If the ebay is large enough, it can be convenient to simply
2225 mount the altimeter at one end and stretch the antenna out
2226 inside. Taping the antenna to the sled can keep it straight
2227 under acceleration. If there are metal rods, keep the
2228 antenna as far away as possible.
2230 For a shorter ebay, it's quite practical to have the antenna
2231 run through a bulkhead and into an adjacent bay. Drill a small
2232 hole in the bulkhead, pass the antenna wire through it and
2233 then seal it up with glue or clay. We've also used acrylic
2234 tubing to create a cavity for the antenna wire. This works a
2235 bit better in that the antenna is known to stay straight and
2236 not get folded by recovery components in the bay. Angle the
2237 tubing towards the side wall of the rocket and it ends up
2238 consuming very little space.
2240 If you need to place the UHF antenna at a distance from the
2241 altimeter, you can replace the antenna with an edge-mounted
2242 SMA connector, and then run 50Ω coax from the board to the
2243 antenna. Building a remote antenna is beyond the scope of this
2245 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49518704"></a>3. Preserving GPS Reception</h2></div></div></div><p>
2246 The GPS antenna and receiver used in TeleMetrum and TeleMega is
2247 highly sensitive and normally have no trouble tracking enough
2248 satellites to provide accurate position information for
2249 recovering the rocket. However, there are many ways the GPS signal
2250 can end up attenuated, negatively affecting GPS performance.
2251 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2252 Conductive tubing or coatings. Carbon fiber and metal
2253 tubing, or metallic paint will all dramatically attenuate the
2254 GPS signal. We've never heard of anyone successfully
2255 receiving GPS from inside these materials.
2256 </p></li><li class="listitem"><p>
2257 Metal components near the GPS patch antenna. These will
2258 de-tune the patch antenna, changing the resonant frequency
2259 away from the L1 carrier and reduce the effectiveness of the
2260 antenna. You can place as much stuff as you like beneath the
2261 antenna as that's covered with a ground plane. But, keep
2262 wires and metal out from above the patch antenna.
2263 </p></li></ol></div><p>
2264 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49523488"></a>4. Radio Frequency Interference</h2></div></div></div><p>
2265 Any altimeter will generate RFI; the digital circuits use
2266 high-frequency clocks that spray radio interference across a
2267 wide band. Altus Metrum altimeters generate intentional radio
2268 signals as well, increasing the amount of RF energy around the board.
2270 Rocketry altimeters also use precise sensors measuring air
2271 pressure and acceleration. Tiny changes in voltage can cause
2272 these sensor readings to vary by a huge amount. When the
2273 sensors start mis-reporting data, the altimeter can either
2274 fire the igniters at the wrong time, or not fire them at all.
2276 Voltages are induced when radio frequency energy is
2277 transmitted from one circuit to another. Here are things that
2278 influence the induced voltage and current:
2279 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2280 Keep wires from different circuits apart. Moving circuits
2281 further apart will reduce RFI.
2282 </p></li><li class="listitem"><p>
2283 Avoid parallel wires from different circuits. The longer two
2284 wires run parallel to one another, the larger the amount of
2285 transferred energy. Cross wires at right angles to reduce
2287 </p></li><li class="listitem"><p>
2288 Twist wires from the same circuits. Two wires the same
2289 distance from the transmitter will get the same amount of
2290 induced energy which will then cancel out. Any time you have
2291 a wire pair running together, twist the pair together to
2292 even out distances and reduce RFI. For altimeters, this
2293 includes battery leads, switch hookups and igniter
2295 </p></li><li class="listitem"><p>
2296 Avoid resonant lengths. Know what frequencies are present
2297 in the environment and avoid having wire lengths near a
2298 natural resonant length. Altus Metrum products transmit on the
2299 70cm amateur band, so you should avoid lengths that are a
2300 simple ratio of that length; essentially any multiple of ¼
2301 of the wavelength (17.5cm).
2302 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49531056"></a>5. The Barometric Sensor</h2></div></div></div><p>
2303 Altusmetrum altimeters measure altitude with a barometric
2304 sensor, essentially measuring the amount of air above the
2305 rocket to figure out how high it is. A large number of
2306 measurements are taken as the altimeter initializes itself to
2307 figure out the pad altitude. Subsequent measurements are then
2308 used to compute the height above the pad.
2310 To accurately measure atmospheric pressure, the ebay
2311 containing the altimeter must be vented outside the
2312 air-frame. The vent must be placed in a region of linear
2313 airflow, have smooth edges, and away from areas of increasing or
2314 decreasing pressure.
2316 All barometric sensors are quite sensitive to chemical damage from
2317 the products of APCP or BP combustion, so make sure the ebay is
2318 carefully sealed from any compartment which contains ejection
2320 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49533856"></a>6. Ground Testing</h2></div></div></div><p>
2321 The most important aspect of any installation is careful
2322 ground testing. Bringing an air-frame up to the LCO table which
2323 hasn't been ground tested can lead to delays or ejection
2324 charges firing on the pad, or, even worse, a recovery system
2327 Do a 'full systems' test that includes wiring up all igniters
2328 without any BP and turning on all of the electronics in flight
2329 mode. This will catch any mistakes in wiring and any residual
2330 RFI issues that might accidentally fire igniters at the wrong
2331 time. Let the air-frame sit for several minutes, checking for
2332 adequate telemetry signal strength and GPS lock. If any igniters
2333 fire unexpectedly, find and resolve the issue before loading any
2336 Ground test the ejection charges. Prepare the rocket for
2337 flight, loading ejection charges and igniters. Completely
2338 assemble the air-frame and then use the 'Fire Igniters'
2339 interface through a TeleDongle to command each charge to
2340 fire. Make sure the charge is sufficient to robustly separate
2341 the air-frame and deploy the recovery system.
2342 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49537024"></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="#idp49541072">1.
2343 Updating TeleMega, TeleMetrum v2, EasyMega or EasyMini Firmware
2344 </a></span></dt><dd><dl><dt><span class="section"><a href="#idp49550144">1.1. Recovering From Self-Flashing Failure</a></span></dt></dl></dd><dt><span class="section"><a href="#idp49568720">2. Pair Programming</a></span></dt><dt><span class="section"><a href="#idp49570160">3. Updating TeleMetrum v1.x Firmware</a></span></dt><dt><span class="section"><a href="#idp49583360">4. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp49596912">5. Updating TeleDongle Firmware</a></span></dt></dl></div><p>
2345 TeleMega, TeleMetrum v2, EasyMega and EasyMini are all programmed directly
2346 over their USB connectors (self programming). TeleMetrum v1, TeleMini and
2347 TeleDongle are all programmed by using another device as a
2348 programmer (pair programming). It's important to recognize which
2349 kind of devices you have before trying to reprogram them.
2351 You may wish to begin by ensuring you have current firmware images.
2352 These are distributed as part of the AltOS software bundle that
2353 also includes the AltosUI ground station program. Newer ground
2354 station versions typically work fine with older firmware versions,
2355 so you don't need to update your devices just to try out new
2356 software features. You can always download the most recent
2357 version from <a class="ulink" href="http://www.altusmetrum.org/AltOS/" target="_top">http://www.altusmetrum.org/AltOS/</a>.
2359 If you need to update the firmware on a TeleDongle, we recommend
2360 updating the altimeter first, before updating TeleDongle. However,
2361 note that TeleDongle rarely need to be updated. Any firmware version
2362 1.0.1 or later will work, version 1.2.1 may have improved receiver
2363 performance slightly.
2365 Self-programmable devices (TeleMega, TeleMetrum v2, EasyMega and EasyMini)
2366 are reprogrammed by connecting them to your computer over USB
2367 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49541072"></a>1.
2368 Updating TeleMega, TeleMetrum v2, EasyMega or EasyMini Firmware
2369 </h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2370 Attach a battery and power switch to the target
2371 device. Power up the device.
2372 </p></li><li class="listitem"><p>
2373 Using a Micro USB cable, connect the target device to your
2374 computer's USB socket.
2375 </p></li><li class="listitem"><p>
2376 Run AltosUI, and select 'Flash Image' from the File menu.
2377 </p></li><li class="listitem"><p>
2378 Select the target device in the Device Selection dialog.
2379 </p></li><li class="listitem"><p>
2380 Select the image you want to flash to the device, which
2381 should have a name in the form
2382 <product>-v<product-version>-<software-version>.ihx, such
2383 as TeleMega-v1.0-1.3.0.ihx.
2384 </p></li><li class="listitem"><p>
2385 Make sure the configuration parameters are reasonable
2386 looking. If the serial number and/or RF configuration
2387 values aren't right, you'll need to change them.
2388 </p></li><li class="listitem"><p>
2389 Hit the 'OK' button and the software should proceed to flash
2390 the device with new firmware, showing a progress bar.
2391 </p></li><li class="listitem"><p>
2392 Verify that the device is working by using the 'Configure
2393 Altimeter' item to check over the configuration.
2394 </p></li></ol></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp49550144"></a>1.1. Recovering From Self-Flashing Failure</h3></div></div></div><p>
2395 If the firmware loading fails, it can leave the device
2396 unable to boot. Not to worry, you can force the device to
2397 start the boot loader instead, which will let you try to
2398 flash the device again.
2400 On each device, connecting two pins from one of the exposed
2401 connectors will force the boot loader to start, even if the
2402 regular operating system has been corrupted in some way.
2403 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">TeleMega</span></dt><dd><p>
2404 Connect pin 6 and pin 1 of the companion connector. Pin 1
2405 can be identified by the square pad around it, and then
2406 the pins could sequentially across the board. Be very
2407 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
2408 anything as that is connected directly to the battery. Pin
2409 7 carries 3.3V and the board will crash if that is
2410 connected to pin 1, but shouldn't damage the board.
2411 </p></dd><dt><span class="term">EasyMega</span></dt><dd><p>
2412 Connect pin 6 and pin 1 of the companion connector. Pin 1
2413 can be identified by the square pad around it, and then
2414 the pins could sequentially across the board. Be very
2415 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
2416 anything as that is connected directly to the battery. Pin
2417 7 carries 3.3V and the board will crash if that is
2418 connected to pin 1, but shouldn't damage the board.
2419 </p></dd><dt><span class="term">TeleMetrum v2</span></dt><dd><p>
2420 Connect pin 6 and pin 1 of the companion connector. Pin 1
2421 can be identified by the square pad around it, and then
2422 the pins could sequentially across the board. Be very
2423 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
2424 anything as that is connected directly to the battery. Pin
2425 7 carries 3.3V and the board will crash if that is
2426 connected to pin 1, but shouldn't damage the board.
2427 </p></dd><dt><span class="term">EasyMini</span></dt><dd><p>
2428 Connect pin 6 and pin 1 of the debug connector, which is
2429 the six holes next to the beeper. Pin 1 can be identified
2430 by the square pad around it, and then the pins could
2431 sequentially across the board, making Pin 6 the one on the
2432 other end of the row.
2433 </p></dd></dl></div><p>
2434 Once you've located the right pins:
2435 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2436 Turn the altimeter power off.
2437 </p></li><li class="listitem"><p>
2439 </p></li><li class="listitem"><p>
2440 Connect the indicated terminals together with a short
2441 piece of wire. Take care not to accidentally connect
2443 </p></li><li class="listitem"><p>
2445 </p></li><li class="listitem"><p>
2446 Turn the board power on.
2447 </p></li><li class="listitem"><p>
2448 The board should now be visible over USB as 'AltosFlash'
2449 and be ready to receive firmware.
2450 </p></li><li class="listitem"><p>
2451 Once the board has been powered up, you can remove the
2453 </p></li></ol></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49568720"></a>2. Pair Programming</h2></div></div></div><p>
2454 The big concept to understand is that you have to use a
2455 TeleMega, TeleMetrum or TeleDongle as a programmer to update a
2456 pair programmed device. Due to limited memory resources in the
2457 cc1111, we don't support programming directly over USB for these
2459 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49570160"></a>3. Updating TeleMetrum v1.x Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2460 Find the 'programming cable' that you got as part of the starter
2461 kit, that has a red 8-pin MicroMaTch connector on one end and a
2462 red 4-pin MicroMaTch connector on the other end.
2463 </p></li><li class="listitem"><p>
2464 Take the 2 screws out of the TeleDongle case to get access
2465 to the circuit board.
2466 </p></li><li class="listitem"><p>
2467 Plug the 8-pin end of the programming cable to the
2468 matching connector on the TeleDongle, and the 4-pin end to the
2469 matching connector on the TeleMetrum.
2470 Note that each MicroMaTch connector has an alignment pin that
2471 goes through a hole in the PC board when you have the cable
2473 </p></li><li class="listitem"><p>
2474 Attach a battery to the TeleMetrum board.
2475 </p></li><li class="listitem"><p>
2476 Plug the TeleDongle into your computer's USB port, and power
2478 </p></li><li class="listitem"><p>
2479 Run AltosUI, and select 'Flash Image' from the File menu.
2480 </p></li><li class="listitem"><p>
2481 Pick the TeleDongle device from the list, identifying it as the
2483 </p></li><li class="listitem"><p>
2484 Select the image you want put on the TeleMetrum, which should have a
2485 name in the form telemetrum-v1.2-1.0.0.ihx. It should be visible
2486 in the default directory, if not you may have to poke around
2487 your system to find it.
2488 </p></li><li class="listitem"><p>
2489 Make sure the configuration parameters are reasonable
2490 looking. If the serial number and/or RF configuration
2491 values aren't right, you'll need to change them.
2492 </p></li><li class="listitem"><p>
2493 Hit the 'OK' button and the software should proceed to flash
2494 the TeleMetrum with new firmware, showing a progress bar.
2495 </p></li><li class="listitem"><p>
2496 Confirm that the TeleMetrum board seems to have updated OK, which you
2497 can do by plugging in to it over USB and using a terminal program
2498 to connect to the board and issue the 'v' command to check
2500 </p></li><li class="listitem"><p>
2501 If something goes wrong, give it another try.
2502 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49583360"></a>4. Updating TeleMini Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2503 You'll need a special 'programming cable' to reprogram the
2504 TeleMini. You can make your own using an 8-pin MicroMaTch
2505 connector on one end and a set of four pins on the other.
2506 </p></li><li class="listitem"><p>
2507 Take the 2 screws out of the TeleDongle case to get access
2508 to the circuit board.
2509 </p></li><li class="listitem"><p>
2510 Plug the 8-pin end of the programming cable to the matching
2511 connector on the TeleDongle, and the 4-pins into the holes
2512 in the TeleMini circuit board. Note that the MicroMaTch
2513 connector has an alignment pin that goes through a hole in
2514 the PC board when you have the cable oriented correctly, and
2515 that pin 1 on the TeleMini board is marked with a square pad
2516 while the other pins have round pads.
2517 </p></li><li class="listitem"><p>
2518 Attach a battery to the TeleMini board.
2519 </p></li><li class="listitem"><p>
2520 Plug the TeleDongle into your computer's USB port, and power
2522 </p></li><li class="listitem"><p>
2523 Run AltosUI, and select 'Flash Image' from the File menu.
2524 </p></li><li class="listitem"><p>
2525 Pick the TeleDongle device from the list, identifying it as the
2527 </p></li><li class="listitem"><p>
2528 Select the image you want put on the TeleMini, which should have a
2529 name in the form telemini-v1.0-1.0.0.ihx. It should be visible
2530 in the default directory, if not you may have to poke around
2531 your system to find it.
2532 </p></li><li class="listitem"><p>
2533 Make sure the configuration parameters are reasonable
2534 looking. If the serial number and/or RF configuration
2535 values aren't right, you'll need to change them.
2536 </p></li><li class="listitem"><p>
2537 Hit the 'OK' button and the software should proceed to flash
2538 the TeleMini with new firmware, showing a progress bar.
2539 </p></li><li class="listitem"><p>
2540 Confirm that the TeleMini board seems to have updated OK, which you
2541 can do by configuring it over the radio link through the TeleDongle, or
2542 letting it come up in “flight” mode and listening for telemetry.
2543 </p></li><li class="listitem"><p>
2544 If something goes wrong, give it another try.
2545 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49596912"></a>5. Updating TeleDongle Firmware</h2></div></div></div><p>
2546 Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
2547 firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
2548 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2549 Find the 'programming cable' that you got as part of the starter
2550 kit, that has a red 8-pin MicroMaTch connector on one end and a
2551 red 4-pin MicroMaTch connector on the other end.
2552 </p></li><li class="listitem"><p>
2553 Find the USB cable that you got as part of the starter kit, and
2554 plug the “mini” end in to the mating connector on TeleMetrum or TeleDongle.
2555 </p></li><li class="listitem"><p>
2556 Take the 2 screws out of the TeleDongle case to get access
2557 to the circuit board.
2558 </p></li><li class="listitem"><p>
2559 Plug the 8-pin end of the programming cable to the
2560 matching connector on the programmer, and the 4-pin end to the
2561 matching connector on the TeleDongle.
2562 Note that each MicroMaTch connector has an alignment pin that
2563 goes through a hole in the PC board when you have the cable
2565 </p></li><li class="listitem"><p>
2566 Attach a battery to the TeleMetrum board if you're using one.
2567 </p></li><li class="listitem"><p>
2568 Plug both the programmer and the TeleDongle into your computer's USB
2569 ports, and power up the programmer.
2570 </p></li><li class="listitem"><p>
2571 Run AltosUI, and select 'Flash Image' from the File menu.
2572 </p></li><li class="listitem"><p>
2573 Pick the programmer device from the list, identifying it as the
2575 </p></li><li class="listitem"><p>
2576 Select the image you want put on the TeleDongle, which should have a
2577 name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
2578 in the default directory, if not you may have to poke around
2579 your system to find it.
2580 </p></li><li class="listitem"><p>
2581 Make sure the configuration parameters are reasonable
2582 looking. If the serial number and/or RF configuration
2583 values aren't right, you'll need to change them. The TeleDongle
2584 serial number is on the “bottom” of the circuit board, and can
2585 usually be read through the translucent blue plastic case without
2586 needing to remove the board from the case.
2587 </p></li><li class="listitem"><p>
2588 Hit the 'OK' button and the software should proceed to flash
2589 the TeleDongle with new firmware, showing a progress bar.
2590 </p></li><li class="listitem"><p>
2591 Confirm that the TeleDongle board seems to have updated OK, which you
2592 can do by plugging in to it over USB and using a terminal program
2593 to connect to the board and issue the 'v' command to check
2594 the version, etc. Once you're happy, remove the programming cable
2595 and put the cover back on the TeleDongle.
2596 </p></li><li class="listitem"><p>
2597 If something goes wrong, give it another try.
2598 </p></li></ol></div><p>
2599 Be careful removing the programming cable from the locking 8-pin
2600 connector on TeleMetrum. You'll need a fingernail or perhaps a thin
2601 screwdriver or knife blade to gently pry the locking ears out
2602 slightly to extract the connector. We used a locking connector on
2603 TeleMetrum to help ensure that the cabling to companion boards
2604 used in a rocket don't ever come loose accidentally in flight.
2605 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49613536"></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="#idp49614176">1.
2606 TeleMega Specifications
2607 </a></span></dt><dt><span class="section"><a href="#idp49625648">2.
2608 EasyMega Specifications
2609 </a></span></dt><dt><span class="section"><a href="#idp49635392">3.
2610 TeleMetrum v2 Specifications
2611 </a></span></dt><dt><span class="section"><a href="#idp49645952">4. TeleMetrum v1 Specifications</a></span></dt><dt><span class="section"><a href="#idp49656512">5.
2612 TeleMini v2.0 Specifications
2613 </a></span></dt><dt><span class="section"><a href="#idp49665344">6.
2614 TeleMini v1.0 Specifications
2615 </a></span></dt><dt><span class="section"><a href="#idp49674144">7.
2616 EasyMini Specifications
2617 </a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49614176"></a>1.
2618 TeleMega Specifications
2619 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2620 Recording altimeter for model rocketry.
2621 </p></li><li class="listitem"><p>
2622 Supports dual deployment and four auxiliary pyro channels
2623 (a total of 6 events).
2624 </p></li><li class="listitem"><p>
2625 70cm 40mW ham-band transceiver for telemetry down-link.
2626 </p></li><li class="listitem"><p>
2627 Barometric pressure sensor good to 100k feet MSL.
2628 </p></li><li class="listitem"><p>
2629 1-axis high-g accelerometer for motor characterization, capable of
2631 </p></li><li class="listitem"><p>
2632 9-axis IMU including integrated 3-axis accelerometer,
2633 3-axis gyroscope and 3-axis magnetometer.
2634 </p></li><li class="listitem"><p>
2635 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
2636 </p></li><li class="listitem"><p>
2637 On-board 8 Megabyte non-volatile memory for flight data storage.
2638 </p></li><li class="listitem"><p>
2639 USB interface for battery charging, configuration, and data recovery.
2640 </p></li><li class="listitem"><p>
2641 Fully integrated support for Li-Po rechargeable batteries.
2642 </p></li><li class="listitem"><p>
2643 Can use either main system Li-Po or optional separate pyro battery
2645 </p></li><li class="listitem"><p>
2646 3.25 x 1.25 inch board designed to fit inside 38mm air-frame coupler tube.
2647 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49625648"></a>2.
2648 EasyMega Specifications
2649 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2650 Recording altimeter for model rocketry.
2651 </p></li><li class="listitem"><p>
2652 Supports dual deployment and four auxiliary pyro channels
2653 (a total of 6 events).
2654 </p></li><li class="listitem"><p>
2655 Barometric pressure sensor good to 100k feet MSL.
2656 </p></li><li class="listitem"><p>
2657 1-axis high-g accelerometer for motor characterization, capable of
2659 </p></li><li class="listitem"><p>
2660 9-axis IMU including integrated 3-axis accelerometer,
2661 3-axis gyroscope and 3-axis magnetometer.
2662 </p></li><li class="listitem"><p>
2663 On-board 8 Megabyte non-volatile memory for flight data storage.
2664 </p></li><li class="listitem"><p>
2665 USB interface for battery charging, configuration, and data recovery.
2666 </p></li><li class="listitem"><p>
2667 Fully integrated support for Li-Po rechargeable batteries.
2668 </p></li><li class="listitem"><p>
2669 Can use either main system Li-Po or optional separate pyro battery
2671 </p></li><li class="listitem"><p>
2672 1.25 x 1.25 inch board designed to fit inside 38mm air-frame coupler tube.
2673 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49635392"></a>3.
2674 TeleMetrum v2 Specifications
2675 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2676 Recording altimeter for model rocketry.
2677 </p></li><li class="listitem"><p>
2678 Supports dual deployment (can fire 2 ejection charges).
2679 </p></li><li class="listitem"><p>
2680 70cm, 40mW ham-band transceiver for telemetry down-link.
2681 </p></li><li class="listitem"><p>
2682 Barometric pressure sensor good to 100k feet MSL.
2683 </p></li><li class="listitem"><p>
2684 1-axis high-g accelerometer for motor characterization, capable of
2686 </p></li><li class="listitem"><p>
2687 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
2688 </p></li><li class="listitem"><p>
2689 On-board 8 Megabyte non-volatile memory for flight data storage.
2690 </p></li><li class="listitem"><p>
2691 USB interface for battery charging, configuration, and data recovery.
2692 </p></li><li class="listitem"><p>
2693 Fully integrated support for Li-Po rechargeable batteries.
2694 </p></li><li class="listitem"><p>
2695 Uses Li-Po to fire e-matches, can be modified to support
2696 optional separate pyro battery if needed.
2697 </p></li><li class="listitem"><p>
2698 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
2699 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49645952"></a>4. TeleMetrum v1 Specifications</h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2700 Recording altimeter for model rocketry.
2701 </p></li><li class="listitem"><p>
2702 Supports dual deployment (can fire 2 ejection charges).
2703 </p></li><li class="listitem"><p>
2704 70cm, 10mW ham-band transceiver for telemetry down-link.
2705 </p></li><li class="listitem"><p>
2706 Barometric pressure sensor good to 45k feet MSL.
2707 </p></li><li class="listitem"><p>
2708 1-axis high-g accelerometer for motor characterization, capable of
2709 +/- 50g using default part.
2710 </p></li><li class="listitem"><p>
2711 On-board, integrated GPS receiver with 5Hz update rate capability.
2712 </p></li><li class="listitem"><p>
2713 On-board 1 megabyte non-volatile memory for flight data storage.
2714 </p></li><li class="listitem"><p>
2715 USB interface for battery charging, configuration, and data recovery.
2716 </p></li><li class="listitem"><p>
2717 Fully integrated support for Li-Po rechargeable batteries.
2718 </p></li><li class="listitem"><p>
2719 Uses Li-Po to fire e-matches, can be modified to support
2720 optional separate pyro battery if needed.
2721 </p></li><li class="listitem"><p>
2722 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
2723 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49656512"></a>5.
2724 TeleMini v2.0 Specifications
2725 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2726 Recording altimeter for model rocketry.
2727 </p></li><li class="listitem"><p>
2728 Supports dual deployment (can fire 2 ejection charges).
2729 </p></li><li class="listitem"><p>
2730 70cm, 10mW ham-band transceiver for telemetry down-link.
2731 </p></li><li class="listitem"><p>
2732 Barometric pressure sensor good to 100k feet MSL.
2733 </p></li><li class="listitem"><p>
2734 On-board 1 megabyte non-volatile memory for flight data storage.
2735 </p></li><li class="listitem"><p>
2736 USB interface for configuration, and data recovery.
2737 </p></li><li class="listitem"><p>
2738 Support for Li-Po rechargeable batteries (using an
2739 external charger), or any 3.7-15V external battery.
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 1.5 x .8 inch board designed to fit inside 24mm 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="idp49665344"></a>6.
2746 TeleMini v1.0 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 45k feet MSL.
2755 </p></li><li class="listitem"><p>
2756 On-board 5 kilobyte non-volatile memory for flight data storage.
2757 </p></li><li class="listitem"><p>
2758 RF interface for configuration, and data recovery.
2759 </p></li><li class="listitem"><p>
2760 Support for Li-Po rechargeable batteries, using an external charger.
2761 </p></li><li class="listitem"><p>
2762 Uses Li-Po to fire e-matches, can be modified to support
2763 optional separate pyro battery if needed.
2764 </p></li><li class="listitem"><p>
2765 1.5 x .5 inch board designed to fit inside 18mm air-frame coupler tube.
2766 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49674144"></a>7.
2767 EasyMini Specifications
2768 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2769 Recording altimeter for model rocketry.
2770 </p></li><li class="listitem"><p>
2771 Supports dual deployment (can fire 2 ejection charges).
2772 </p></li><li class="listitem"><p>
2773 Barometric pressure sensor good to 100k feet MSL.
2774 </p></li><li class="listitem"><p>
2775 On-board 1 megabyte non-volatile memory for flight data storage.
2776 </p></li><li class="listitem"><p>
2777 USB interface for configuration, and data recovery.
2778 </p></li><li class="listitem"><p>
2779 Support for Li-Po rechargeable batteries (using an
2780 external charger), or any 3.7-15V external battery.
2781 </p></li><li class="listitem"><p>
2782 Uses Li-Po to fire e-matches, can be modified to support
2783 optional separate pyro battery if needed.
2784 </p></li><li class="listitem"><p>
2785 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
2786 </p></li></ul></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49682256"></a>Chapter 12. FAQ</h1></div></div></div><p>
2787 <span class="emphasis"><em>TeleMetrum seems to shut off when disconnected from the
2788 computer.</em></span>
2789 Make sure the battery is adequately charged. Remember the
2790 unit will pull more power than the USB port can deliver before the
2791 GPS enters “locked” mode. The battery charges best when TeleMetrum
2794 <span class="emphasis"><em>It's impossible to stop the TeleDongle when it's in “p” mode, I have
2795 to unplug the USB cable? </em></span>
2796 Make sure you have tried to “escape out” of
2797 this mode. If this doesn't work the reboot procedure for the
2798 TeleDongle *is* to simply unplug it. 'cu' however will retain it's
2799 outgoing buffer IF your “escape out” ('~~') does not work.
2800 At this point using either 'ao-view' (or possibly
2801 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
2804 <span class="emphasis"><em>The amber LED (on the TeleMetrum) lights up when both
2805 battery and USB are connected. Does this mean it's charging?
2807 Yes, the yellow LED indicates the charging at the 'regular' rate.
2808 If the led is out but the unit is still plugged into a USB port,
2809 then the battery is being charged at a 'trickle' rate.
2811 <span class="emphasis"><em>There are no “dit-dah-dah-dit” sound or lights like the manual
2812 mentions?</em></span>
2813 That's the “pad” mode. Weak batteries might be the problem.
2814 It is also possible that the flight computer is horizontal and the
2816 is instead a “dit-dit” meaning 'idle'. For TeleMini, it's possible that
2817 it received a command packet which would have left it in “pad” mode.
2819 <span class="emphasis"><em>How do I save flight data?</em></span>
2820 Live telemetry is written to file(s) whenever AltosUI is connected
2821 to the TeleDongle. The file area defaults to ~/TeleMetrum
2822 but is easily changed using the menus in AltosUI. The files that
2823 are written end in '.telem'. The after-flight
2824 data-dumped files will end in .eeprom and represent continuous data
2825 unlike the .telem files that are subject to losses
2826 along the RF data path.
2827 See the above instructions on what and how to save the eeprom stored
2828 data after physically retrieving your altimeter. Make sure to save
2829 the on-board data after each flight; while the TeleMetrum can store
2830 multiple flights, you never know when you'll lose the altimeter...
2831 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp49691104"></a>Appendix A. Notes for Older Software</h1></div></div></div><p>
2832 <span class="emphasis"><em>
2833 Before AltosUI was written, using Altus Metrum devices required
2834 some finesse with the Linux command line. There was a limited
2835 GUI tool, ao-view, which provided functionality similar to the
2836 Monitor Flight window in AltosUI, but everything else was a
2837 fairly 80's experience. This appendix includes documentation for
2838 using that software.
2841 Both TeleMetrum and TeleDongle can be directly communicated
2842 with using USB ports. The first thing you should try after getting
2843 both units plugged into to your computer's USB port(s) is to run
2844 'ao-list' from a terminal-window to see what port-device-name each
2845 device has been assigned by the operating system.
2846 You will need this information to access the devices via their
2847 respective on-board firmware and data using other command line
2848 programs in the AltOS software suite.
2850 TeleMini can be communicated with through a TeleDongle device
2851 over the radio link. When first booted, TeleMini listens for a
2852 TeleDongle device and if it receives a packet, it goes into
2853 'idle' mode. Otherwise, it goes into 'pad' mode and waits to be
2854 launched. The easiest way to get it talking is to start the
2855 communication link on the TeleDongle and the power up the
2858 To access the device's firmware for configuration you need a terminal
2859 program such as you would use to talk to a modem. The software
2860 authors prefer using the program 'cu' which comes from the UUCP package
2861 on most Unix-like systems such as Linux. An example command line for
2862 cu might be 'cu -l /dev/ttyACM0', substituting the correct number
2863 indicated from running the
2864 ao-list program. Another reasonable terminal program for Linux is
2865 'cutecom'. The default 'escape'
2866 character used by CU (i.e. the character you use to
2867 issue commands to cu itself instead of sending the command as input
2868 to the connected device) is a '~'. You will need this for use in
2869 only two different ways during normal operations. First is to exit
2870 the program by sending a '~.' which is called a 'escape-disconnect'
2871 and allows you to close-out from 'cu'. The
2872 second use will be outlined later.
2874 All of the Altus Metrum devices share the concept of a two level
2875 command set in their firmware.
2876 The first layer has several single letter commands. Once
2877 you are using 'cu' (or 'cutecom') sending (typing) a '?'
2878 returns a full list of these
2879 commands. The second level are configuration sub-commands accessed
2880 using the 'c' command, for
2881 instance typing 'c?' will give you this second level of commands
2882 (all of which require the
2883 letter 'c' to access). Please note that most configuration options
2884 are stored only in Flash memory; TeleDongle doesn't provide any storage
2885 for these options and so they'll all be lost when you unplug it.
2887 Try setting these configuration ('c' or second level menu) values. A good
2888 place to start is by setting your call sign. By default, the boards
2889 use 'N0CALL' which is cute, but not exactly legal!
2890 Spend a few minutes getting comfortable with the units, their
2891 firmware, and 'cu' (or possibly 'cutecom').
2892 For instance, try to send
2893 (type) a 'c r 2' and verify the channel change by sending a 'c s'.
2894 Verify you can connect and disconnect from the units while in your
2895 terminal program by sending the escape-disconnect mentioned above.
2897 To set the radio frequency, use the 'c R' command to specify the
2898 radio transceiver configuration parameter. This parameter is computed
2899 using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
2900 the standard calibration reference frequency, 'S', (normally 434.550MHz):
2901 </p><pre class="programlisting">
2904 Round the result to the nearest integer value.
2905 As with all 'c' sub-commands, follow this with a 'c w' to write the
2906 change to the parameter block in the on-board flash on
2907 your altimeter board if you want the change to stay in place across reboots.
2909 To set the apogee delay, use the 'c d' command.
2910 As with all 'c' sub-commands, follow this with a 'c w' to write the
2911 change to the parameter block in the on-board DataFlash chip.
2913 To set the main deployment altitude, use the 'c m' command.
2914 As with all 'c' sub-commands, follow this with a 'c w' to write the
2915 change to the parameter block in the on-board DataFlash chip.
2917 To calibrate the radio frequency, connect the UHF antenna port to a
2918 frequency counter, set the board to 434.550MHz, and use the 'C'
2919 command to generate a CW carrier. Wait for the transmitter temperature
2920 to stabilize and the frequency to settle down.
2921 Then, divide 434.550 MHz by the
2922 measured frequency and multiply by the current radio cal value show
2923 in the 'c s' command. For an unprogrammed board, the default value
2924 is 1186611 for cc1111 based products and 7119667 for cc1120
2925 based products. Take the resulting integer and program it using the 'c f'
2926 command. Testing with the 'C' command again should show a carrier
2927 within a few tens of Hertz of the intended frequency.
2928 As with all 'c' sub-commands, follow this with a 'c w' to write the
2929 change to the configuration memory.
2931 Note that the 'reboot' command, which is very useful on the altimeters,
2932 will likely just cause problems with the dongle. The *correct* way
2933 to reset the dongle is just to unplug and re-plug it.
2935 A fun thing to do at the launch site and something you can do while
2936 learning how to use these units is to play with the radio link access
2937 between an altimeter and the TeleDongle. Be aware that you *must* create
2938 some physical separation between the devices, otherwise the link will
2939 not function due to signal overload in the receivers in each device.
2941 Now might be a good time to take a break and read the rest of this
2942 manual, particularly about the two “modes” that the altimeters
2943 can be placed in. TeleMetrum uses the position of the device when booting
2944 up will determine whether the unit is in “pad” or “idle” mode. TeleMini
2945 enters “idle” mode when it receives a command packet within the first 5 seconds
2946 of being powered up, otherwise it enters “pad” mode.
2948 You can access an altimeter in idle mode from the TeleDongle's USB
2949 connection using the radio link
2950 by issuing a 'p' command to the TeleDongle. Practice connecting and
2951 disconnecting ('~~' while using 'cu') from the altimeter. If
2952 you cannot escape out of the “p” command, (by using a '~~' when in
2953 CU) then it is likely that your kernel has issues. Try a newer version.
2955 Using this radio link allows you to configure the altimeter, test
2956 fire e-matches and igniters from the flight line, check pyro-match
2957 continuity and so forth. You can leave the unit turned on while it
2958 is in 'idle mode' and then place the
2959 rocket vertically on the launch pad, walk away and then issue a
2960 reboot command. The altimeter will reboot and start sending data
2961 having changed to the “pad” mode. If the TeleDongle is not receiving
2962 this data, you can disconnect 'cu' from the TeleDongle using the
2963 procedures mentioned above and THEN connect to the TeleDongle from
2964 inside 'ao-view'. If this doesn't work, disconnect from the
2965 TeleDongle, unplug it, and try again after plugging it back in.
2967 In order to reduce the chance of accidental firing of pyrotechnic
2968 charges, the command to fire a charge is intentionally somewhat
2969 difficult to type, and the built-in help is slightly cryptic to
2970 prevent accidental echoing of characters from the help text back at
2971 the board from firing a charge. The command to fire the apogee
2972 drogue charge is 'i DoIt drogue' and the command to fire the main
2973 charge is 'i DoIt main'.
2975 On TeleMetrum, the GPS will eventually find enough satellites, lock in on them,
2976 and 'ao-view' will both auditorily announce and visually indicate
2978 Now you can launch knowing that you have a good data path and
2979 good satellite lock for flight data and recovery. Remember
2980 you MUST tell ao-view to connect to the TeleDongle explicitly in
2981 order for ao-view to be able to receive data.
2983 The altimeters provide RDF (radio direction finding) tones on
2984 the pad, during descent and after landing. These can be used to
2985 locate the rocket using a directional antenna; the signal
2986 strength providing an indication of the direction from receiver to rocket.
2988 TeleMetrum also provides GPS tracking data, which can further simplify
2989 locating the rocket once it has landed. (The last good GPS data
2990 received before touch-down will be on the data screen of 'ao-view'.)
2992 Once you have recovered the rocket you can download the eeprom
2993 contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
2994 either a USB cable or over the radio link using TeleDongle.
2995 And by following the man page for 'ao-postflight' you can create
2996 various data output reports, graphs, and even KML data to see the
2997 flight trajectory in Google-earth. (Moving the viewing angle making
2998 sure to connect the yellow lines while in Google-earth is the proper
3001 As for ao-view.... some things are in the menu but don't do anything
3002 very useful. The developers have stopped working on ao-view to focus
3003 on a new, cross-platform ground station program. So ao-view may or
3004 may not be updated in the future. Mostly you just use
3005 the Log and Device menus. It has a wonderful display of the incoming
3006 flight data and I am sure you will enjoy what it has to say to you
3007 once you enable the voice output!
3008 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp49713504"></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="#idp49714672">1. TeleMega template</a></span></dt><dt><span class="section"><a href="#idp49731360">2. EasyMega template</a></span></dt><dt><span class="section"><a href="#idp49735744">3. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp49740128">4. TeleMini v2/EasyMini template</a></span></dt><dt><span class="section"><a href="#idp49744528">5. TeleMini v1 template</a></span></dt></dl></div><p>
3009 These images, when printed, provide precise templates for the
3010 mounting holes in Altus Metrum flight computers
3011 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49714672"></a>1. TeleMega template</h2></div></div></div><p>
3012 TeleMega has overall dimensions of 1.250 x 3.250 inches, and
3013 the mounting holes are sized for use with 4-40 or M3 screws.
3014 </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="idp49731360"></a>2. EasyMega template</h2></div></div></div><p>
3015 EasyMega has overall dimensions of 1.250 x 2.250 inches, and
3016 the mounting holes are sized for use with 4-40 or M3 screws.
3017 </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="idp49735744"></a>3. TeleMetrum template</h2></div></div></div><p>
3018 TeleMetrum has overall dimensions of 1.000 x 2.750 inches, and the
3019 mounting holes are sized for use with 4-40 or M3 screws.
3020 </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="idp49740128"></a>4. TeleMini v2/EasyMini template</h2></div></div></div><p>
3021 TeleMini v2 and EasyMini have overall dimensions of 0.800 x 1.500 inches, and the
3022 mounting holes are sized for use with 4-40 or M3 screws.
3023 </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="idp49744528"></a>5. TeleMini v1 template</h2></div></div></div><p>
3024 TeleMini has overall dimensions of 0.500 x 1.500 inches, and the
3025 mounting holes are sized for use with 2-56 or M2 screws.
3026 </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="idp49749040"></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="#idp49750592">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp49755136">2. TeleMetrum, TeleMega and EasyMega Accelerometers</a></span></dt></dl></div><p>
3027 There are only two calibrations required for TeleMetrum and
3028 TeleMega, and only one for EasyMega, TeleDongle, TeleMini and EasyMini.
3029 All boards are shipped from the factory pre-calibrated, but
3030 the procedures are documented here in case they are ever
3031 needed. Re-calibration is not supported by AltosUI, you must
3032 connect to the board with a serial terminal program and
3033 interact directly with the on-board command interpreter to
3035 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49750592"></a>1. Radio Frequency</h2></div></div></div><p>
3036 The radio frequency is synthesized from a clock based on the
3037 crystal on the board. The actual frequency of this oscillator
3038 must be measured to generate a calibration constant. While our
3040 bandwidth is wide enough to allow boards to communicate even when
3041 their oscillators are not on exactly the same frequency, performance
3042 is best when they are closely matched.
3043 Radio frequency calibration requires a calibrated frequency counter.
3044 Fortunately, once set, the variation in frequency due to aging and
3045 temperature changes is small enough that re-calibration by customers
3046 should generally not be required.
3048 To calibrate the radio frequency, connect the UHF antenna
3049 port to a frequency counter, set the board to 434.550MHz,
3050 and use the 'C' command in the on-board command interpreter
3051 to generate a CW carrier. For USB-enabled boards, this is
3052 best done over USB. For TeleMini v1, note that the only way
3053 to escape the 'C' command is via power cycle since the board
3054 will no longer be listening for commands once it starts
3055 generating a CW carrier.
3057 Wait for the transmitter temperature to stabilize and the frequency
3058 to settle down. Then, divide 434.550 MHz by the
3059 measured frequency and multiply by the current radio cal value show
3060 in the 'c s' command. For an unprogrammed board, the default value
3061 is 1186611. Take the resulting integer and program it using the 'c f'
3062 command. Testing with the 'C' command again should show a carrier
3063 within a few tens of Hertz of the intended frequency.
3064 As with all 'c' sub-commands, follow this with a 'c w' to write the
3065 change to the parameter block in the on-board storage chip.
3067 Note that any time you re-do the radio frequency calibration, the
3068 radio frequency is reset to the default 434.550 Mhz. If you want
3069 to use another frequency, you will have to set that again after
3070 calibration is completed.
3071 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49755136"></a>2. TeleMetrum, TeleMega and EasyMega Accelerometers</h2></div></div></div><p>
3072 While barometric sensors are factory-calibrated,
3073 accelerometers are not, and so each must be calibrated once
3074 installed in a flight computer. Explicitly calibrating the
3075 accelerometers also allows us to load any compatible device.
3076 We perform a two-point calibration using gravity.
3078 To calibrate the acceleration sensor, use the 'c a 0' command. You
3079 will be prompted to orient the board vertically with the UHF antenna
3080 up and press a key, then to orient the board vertically with the
3081 UHF antenna down and press a key. Note that the accuracy of this
3082 calibration depends primarily on how perfectly vertical and still
3083 the board is held during the cal process. As with all 'c'
3084 sub-commands, follow this with a 'c w' to write the
3085 change to the parameter block in the on-board DataFlash chip.
3087 The +1g and -1g calibration points are included in each telemetry
3088 frame and are part of the header stored in onboard flash to be
3089 downloaded after flight. We always store and return raw ADC
3090 samples for each sensor... so nothing is permanently “lost” or
3091 “damaged” if the calibration is poor.
3093 In the unlikely event an accel cal goes badly, it is possible
3094 that TeleMetrum, TeleMega or EasyMega may always come up in 'pad mode'
3095 and as such not be listening to either the USB or radio link.
3096 If that happens, there is a special hook in the firmware to
3097 force the board back in to 'idle mode' so you can re-do the
3098 cal. To use this hook, you just need to ground the SPI clock
3099 pin at power-on. This pin is available as pin 2 on the 8-pin
3100 companion connector, and pin 1 is ground. So either
3101 carefully install a fine-gauge wire jumper between the two
3102 pins closest to the index hole end of the 8-pin connector, or
3103 plug in the programming cable to the 8-pin connector and use
3104 a small screwdriver or similar to short the two pins closest
3105 to the index post on the 4-pin end of the programming cable,
3106 and power up the board. It should come up in 'idle mode'
3107 (two beeps), allowing a re-cal.
3108 </p></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp49760816"></a>Appendix D. Release Notes</h1></div></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49761456"></a>Version 1.4.1</h2></div></div></div><p>
3109 Version 1.4.1 is a minor release. It fixes install issues on
3110 Windows and provides the missing TeleMetrum V2.0 firmware. There
3111 aren't any changes to the firmware or host applications at
3112 all. All Windows users will want to upgrade to get the signed
3113 driver, but Mac and Linux users who do not need the TeleMetrum
3114 V2.0 firmware image will not need to upgrade.
3116 Windows Install Fixes
3117 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3118 Provide signed Windows driver files. This should avoid any need to
3119 disable driver signature checking on Windows 7 or 8.
3120 </p></li><li class="listitem"><p>
3121 Fix Java version detection and download. Previously, the
3122 installer would only look for Java 6 or 7 and insist on
3123 downloading its own Java bits if there was something else
3124 installed. Furthermore, the 64-bit Java link provided didn't
3125 work for anyone other than Keith, making it impossible to
3126 install AltOS on any machine with Java SE 8 installed.
3127 </p></li></ul></div><p>
3130 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3131 Include 1.4 firmware for TeleMetrum V2.0. None of the
3132 installers shipped this file. Now it's included in the AltOS
3133 packages for Linux, Mac and Windows.
3134 </p></li><li class="listitem"><p>
3135 Include Google Application Key for map downloading. The 1.4
3136 release didn't have this key in the released version of the
3137 software, making map downloading fail for most people.
3138 </p></li></ul></div><p>
3139 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49763056"></a>Version 1.5</h2></div></div></div><p>
3140 Version 1.5 is a major release. It includes support for our new
3141 EasyMega product, new features and bug fixes in in the flight
3142 software for all our boards and the AltosUI ground station
3145 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3146 Add support for EasyMega boards.
3147 </p></li><li class="listitem"><p>
3148 Make the APRS SSID be configurable. This lets you track
3149 different rockets on the same receiver without getting
3151 </p></li><li class="listitem"><p>
3152 Report extra pyro channel continuity state on EasyMega and
3153 TeleMega via the beeper. This lets you easily verify flight
3154 readiness on these boards after powering up the electronics
3156 </p></li><li class="listitem"><p>
3157 Add lower telemetry data rates (2400 and 9600 bps) to
3158 increase telemetry radio range. This reduces the amount of
3159 data received as well as increasing battery consumption in
3161 </p></li><li class="listitem"><p>
3162 Change TeleGPS to have only a single log, and append new
3163 data to it rather than using seperate per-flight logs. This
3164 avoids accidentally filling up log storage by turning
3165 TeleGPS on/off several times.
3166 </p></li></ul></div><p>
3169 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3170 Increase the maximum range for altitude values from +/-32767m
3171 to +/-2147483647m, allowing the flight computers to function
3172 correctly above the 32km level.
3173 </p></li><li class="listitem"><p>
3174 Continuously test pyro firing conditions during delay stage,
3175 inhibiting the pyro channel if the test fails. This prevents
3176 firing pyro charges where the conditions were good before
3177 the delay, but become bad before the delay expires.
3178 </p></li><li class="listitem"><p>
3179 Allow negative numbers in pyro configuration values. This
3180 lets you specify things like descending speed or
3182 </p></li></ul></div><p>
3184 AltosUI and TeleGPS New Features
3185 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3186 Support telemetry baud rate selection. Adds menus to
3187 the flight monitoring and configuration for baud rate
3189 </p></li><li class="listitem"><p>
3190 Support APRS SSID configuration.
3191 </p></li><li class="listitem"><p>
3192 Integrate with file managers. This provides icons for all of
3193 our file types and associates our application with the files
3194 so that using a file manager to open a AltOS data file
3195 results in launching our application.
3196 </p></li></ul></div><p>
3199 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3200 Make the 'Graph' button on the landed tab work again.
3201 </p></li><li class="listitem"><p>
3202 Make tests for Java on Windows a bit smarter, and also
3203 provide the user with the option to skip installing Java for
3204 cases where we just can't figure out what version is installed.
3205 </p></li></ul></div><p>
3206 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49764656"></a>Version 1.4</h2></div></div></div><p>
3207 Version 1.4 is a major release. It includes support for our new
3208 TeleGPS product, new features and bug fixes in in the flight
3209 software for all our boards and the AltosUI ground station
3212 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3213 Add support for TeleGPS boards.
3214 </p></li><li class="listitem"><p>
3215 Replace the 'dit dit dit' tones at startup with the current
3216 battery voltage, measured in tenths of a volt. This lets you
3217 check the battery voltage without needing telemetry, which
3218 is especially useful on EasyMini.
3219 </p></li><li class="listitem"><p>
3220 Change state beeping to "Farnsworth spacing", which means
3221 they're quite a bit faster than before, and so they take
3223 </p></li><li class="listitem"><p>
3224 Make the beeper tone configurable, making it possible to
3225 distinguish between two Altus Metrum products in the same ebay.
3226 </p></li><li class="listitem"><p>
3227 Make the firing time for extra pyro channels configurable,
3228 allowing longer (or shorter) than the default 50ms. Only relevant
3229 for TeleMega at this time.
3230 </p></li></ul></div><p>
3233 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3234 Fix bug preventing the selection of the 'Flight State After'
3235 mode in pyro configuration.
3236 </p></li><li class="listitem"><p>
3237 Fix bug where erasing flights would reset the flight number
3238 to 2 on TeleMega and TeleMetrum v2.
3239 </p></li><li class="listitem"><p>
3240 Fix u-Blox GPS driver to mark course and speed data as being
3242 </p></li></ul></div><p>
3244 AltosUI New Features
3245 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3246 Add zooming and new content types (terrain and road maps) to
3247 map view. Change map storage format from PNG to Jpeg, which
3248 saves a huge amount of disk space. You will need to
3249 re-download all of your pre-loaded map images.
3250 </p></li><li class="listitem"><p>
3251 Add a distance measuring device to the maps view. Select
3252 this by using any button other than the left one, or by
3253 pressing shift or control on the keyboard while using the
3255 </p></li><li class="listitem"><p>
3256 Add new 'Ignitor' tab to the flight monitor display for
3257 TeleMega's extra ignitors.
3258 </p></li><li class="listitem"><p>
3259 Increase the width of data lines in the graphs to make them
3261 </p></li><li class="listitem"><p>
3262 Add additional ignitor firing marks and voltages to the
3263 graph so you can see when the ignitors fired, along with
3264 the ignitor voltages.
3265 </p></li><li class="listitem"><p>
3266 Add GPS course, ground speed and climb rate as optional
3268 </p></li></ul></div><p>
3271 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3272 When flashing new firmware, re-try opening the device as
3273 sometimes it takes a while for the underlying operating
3274 system to recognize that the device has rebooted in
3275 preparation for the flashing operation.
3276 </p></li><li class="listitem"><p>
3277 Hide Tilt Angle in ascent tab for devices that don't have a gyro.
3278 </p></li><li class="listitem"><p>
3279 Filter out speed and acceleration spikes caused by ejection
3280 charge firing when computing the maximum values. This
3281 provides a more accurate reading of those maximums.
3282 </p></li><li class="listitem"><p>
3283 Fix EasyMini voltage displays. Early EasyMini prototypes
3284 used a 3.0V regulator, and AltosUI still used that value as
3285 the basis of the computation. Production EasyMini boards
3286 have always shipped with a 3.3V regulator. Also, purple
3287 EasyMini boards sensed the battery voltage past the blocking
3288 diode, resulting in a drop of about 150mV from the true
3289 battery voltage. Compensate for that when displaying the
3291 </p></li><li class="listitem"><p>
3292 Display error message when trying to configure maximum
3293 flight log size while the flight computer still has flight
3295 </p></li><li class="listitem"><p>
3296 Handle TeleMetrum and TeleMini eeprom files generated with
3297 pre-1.0 firmware. Those ancient versions didn't report the
3298 log format, so just use the product name instead.
3299 </p></li></ul></div><p>
3302 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3303 New application designed for use with TeleGPS boards.
3304 </p></li><li class="listitem"><p>
3305 Shares code with AltosUI, mostly just trimmed down to focus
3306 on TeleGPS-related functions.
3307 </p></li></ul></div><p>
3309 Documentation changes
3310 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3311 Re-create the drill template images; they should print
3312 correctly from Firefox at least. Ship these as individual
3313 PDF files so they're easy to print.
3314 </p></li><li class="listitem"><p>
3315 Add a description of the 'Apogee Lockout' setting, which
3316 prevents the apogee charge from firing for a configurable
3317 amount of time after boost.
3318 </p></li></ul></div><p>
3319 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49766160"></a>Version 1.3.2</h2></div></div></div><p>
3320 Version 1.3.2 is a minor release. It includes small bug fixes for
3321 the TeleMega flight software and AltosUI ground station
3323 AltOS Firmware Changes
3324 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3325 On TeleMega, limit number of logged GPS status information
3326 to 12 satellites. That's all there is room for in the log
3328 </p></li><li class="listitem"><p>
3329 Improve APRS behavior. Remembers last known GPS position and
3330 keeps sending that if we lose GPS lock. Marks
3331 locked/unlocked by sending L/U in the APRS comment field
3332 along with the number of sats in view and voltages.
3333 </p></li></ul></div><p>
3336 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3337 If the TeleMega flight firmware reports that it has logged
3338 information about more than 12 satellites, don't believe it
3339 as the log only holds 12 satellite records.
3340 </p></li><li class="listitem"><p>
3341 Track the maximum height as computed from GPS altitude
3342 data and report that in the flight summary data.
3343 </p></li><li class="listitem"><p>
3344 Use letters (A, B, C, D) for alternate pyro channel names
3345 instead of numbers (0, 1, 2, 3) in the Fire Igniter dialog.
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="idp49767664"></a>Version 1.3.1</h2></div></div></div><p>
3348 Version 1.3.1 is a minor release. It improves support for TeleMega,
3349 TeleMetrum v2.0, TeleMini v2.0 and EasyMini.
3351 AltOS Firmware Changes
3352 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3353 Improve sensor boot code. If sensors fail to self-test, the
3354 device will still boot up and check for pad/idle modes. If
3355 in idle mode, the device will warn the user with a distinct
3356 beep, if in Pad mode, the unit will operate as best it
3357 can. Also, the Z-axis accelerometer now uses the factory
3358 calibration values instead of re-calibrating on the pad each
3359 time. This avoids accidental boost detect when moving the
3360 device around while in Pad mode.
3361 </p></li><li class="listitem"><p>
3362 Fix antenna-down mode accelerometer configuration. Antenna
3363 down mode wasn't working because the accelerometer
3364 calibration values were getting re-computed incorrectly in
3366 </p></li><li class="listitem"><p>
3367 Improved APRS mode. Now uses compressed position format for
3368 smaller data size, improved precision and to include
3369 altitude data as well as latitude and longitude. Also added
3370 battery and pyro voltage reports in the APRS comment field
3371 so you can confirm that the unit is ready for launch.
3372 </p></li></ul></div><p>
3375 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3376 Display additional TeleMega sensor values in real
3377 units. Make all of these values available for
3378 plotting. Display TeleMega orientation value in the Ascent
3380 </p></li><li class="listitem"><p>
3381 Support additional TeleMega pyro channels in the Fire
3382 Igniter dialog. This lets you do remote testing of all of
3383 the channels, rather than just Apogee and Main.
3384 </p></li><li class="listitem"><p>
3385 Limit data rate when downloading satellite images from
3386 Google to make sure we stay within their limits so that all
3387 of the map tiles download successfully.
3388 </p></li></ul></div><p>
3389 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49769168"></a>Version 1.3</h2></div></div></div><p>
3390 Version 1.3 is a major release. It adds support for TeleMega,
3391 TeleMetrum v2.0, TeleMini v2.0 and EasyMini.
3393 AltOS Firmware Changes
3394 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3395 Add STM32L processor support. This includes enhancements to
3396 the scheduler to support products with many threads.
3397 </p></li><li class="listitem"><p>
3398 Add NXP LPC11U14 processor support.
3399 </p></li><li class="listitem"><p>
3400 Support additional pyro channels. These are configurable
3401 through the UI to handle air starts, staging, additional
3402 recovery events and external devices such as cameras.
3403 </p></li><li class="listitem"><p>
3404 Add 3-axis gyro support for orientation tracking. This
3405 integrates the gyros to compute the angle from vertical during
3406 flight, allowing the additional pyro events to be controlled
3408 </p></li><li class="listitem"><p>
3409 Many more device drivers, including u-Blox Max 7Q GPS,
3410 Freescale MMA6555 digital single-axis accelerometer,
3411 Invensense MPU6000 3-axis accelerometer + 3 axis gyro,
3412 Honeywell HMC5883 3-axis magnetic sensor and the TI CC1120 and
3413 CC115L digital FM transceivers
3414 </p></li></ul></div><p>
3417 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3418 Support TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini telemetry and log formats.
3419 </p></li><li class="listitem"><p>
3420 Use preferred units for main deployment height configuration,
3421 instead of always doing configuration in meters.
3422 </p></li></ul></div><p>
3424 MicroPeak UI changes
3425 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3426 Add 'Download' button to menu bar.
3427 </p></li><li class="listitem"><p>
3428 Save the last log directory and offer that as the default for new downloads
3429 </p></li></ul></div><p>
3430 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49770672"></a>Version 1.2.1</h2></div></div></div><p>
3431 Version 1.2.1 is a minor release. It adds support for TeleBT and
3432 the AltosDroid application, provides several new features in
3433 AltosUI and fixes some bugs in the AltOS firmware.
3435 AltOS Firmware Changes
3436 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3437 Add support for TeleBT
3438 </p></li><li class="listitem"><p>
3439 In TeleMini recovery mode (when booted with the outer two
3440 debug pins connected together), the radio parameters are also
3441 set back to defaults (434.550MHz, N0CALL, factory radio cal).
3442 </p></li><li class="listitem"><p>
3443 Add support for reflashing the SkyTraq GPS chips. This
3444 requires special host-side code which currently only exists
3446 </p></li><li class="listitem"><p>
3447 Correct Kalman filter model error covariance matrix. The
3448 values used previously assumed continuous measurements instead
3449 of discrete measurements.
3450 </p></li><li class="listitem"><p>
3451 Fix some bugs in the USB driver for TeleMetrum and TeleDongle
3452 that affected Windows users.
3453 </p></li><li class="listitem"><p>
3454 Adjusted the automatic gain control parameters that affect
3455 receive performance for TeleDongle. Field tests indicate that this
3456 may improve receive performance somewhat.
3457 </p></li></ul></div><p>
3460 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3461 Handle missing GPS lock in 'Descent' tab. Previously, if the
3462 GPS position of the pad was unknown, an exception would be
3463 raised, breaking the Descent tab contents.
3464 </p></li><li class="listitem"><p>
3465 Improve the graph, adding tool-tips to show values near the
3466 cursor and making the displayed set of values configurable,
3467 adding all of the flight data as options while leaving the
3468 default settings alone so that the graph starts by showing
3469 height, speed and acceleration.
3470 </p></li><li class="listitem"><p>
3471 Make the initial position of the AltosUI top level window
3472 configurable. Along with this change, the other windows will
3473 pop up at 'sensible' places now, instead of on top of one
3475 </p></li><li class="listitem"><p>
3476 Add callsign to Monitor idle window and connecting
3477 dialogs. This makes it clear which callsign is being used so
3478 that the operator will be aware that it must match the flight
3479 computer value or no communication will work.
3480 </p></li><li class="listitem"><p>
3481 When downloading flight data, display the block number so that
3482 the user has some sense of progress. Unfortunately, we don't
3483 know how many blocks will need to be downloaded, but at least
3484 it isn't just sitting there doing nothing for a long time.
3485 </p></li><li class="listitem"><p>
3486 Add GPS data and a map to the graph window. This lets you see
3487 a complete summary of the flight without needing to 'replay'
3489 </p></li></ul></div><p>
3490 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49772176"></a>Version 1.2</h2></div></div></div><p>
3491 Version 1.2 is a major release. It adds support for MicroPeak and
3492 the MicroPeak USB adapter.
3494 AltOS Firmware Changes
3495 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3496 Add MicroPeak support. This includes support for the ATtiny85
3497 processor and adaptations to the core code to allow for
3498 devices too small to run the multi-tasking scheduler.
3499 </p></li></ul></div><p>
3501 MicroPeak UI changes
3502 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3503 Added this new application
3504 </p></li></ul></div><p>
3506 Distribution Changes
3507 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3508 Distribute Mac OS X packages in disk image ('.dmg') format to
3509 greatly simplify installation.
3510 </p></li><li class="listitem"><p>
3511 Provide version numbers for the shared Java libraries to
3512 ensure that upgrades work properly, and to allow for multiple
3513 Altus Metrum software packages to be installed in the same
3514 directory at the same time.
3515 </p></li></ul></div><p>
3516 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49773680"></a>Version 1.1.1</h2></div></div></div><p>
3517 Version 1.1.1 is a bug-fix release. It fixes a couple of bugs in
3518 AltosUI and one firmware bug that affects TeleMetrum version 1.0
3519 boards. Thanks to Bob Brown for help diagnosing the Google Earth
3520 file export issue, and for suggesting the addition of the Ground
3521 Distance value in the Descent tab.
3523 AltOS Firmware Changes
3524 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3525 TeleMetrum v1.0 boards use the AT45DB081D flash memory part to
3526 store flight data, which is different from later TeleMetrum
3527 boards. The AltOS v1.1 driver for this chip couldn't erase
3528 memory, leaving it impossible to delete flight data or update
3529 configuration values. This bug doesn't affect newer TeleMetrum
3530 boards, and it doesn't affect the safety of rockets flying
3531 version 1.1 firmware.
3532 </p></li></ul></div><p>
3535 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3536 Creating a Google Earth file (KML) from on-board flight data
3537 (EEPROM) would generate an empty file. The code responsible
3538 for reading the EEPROM file wasn't ever setting the GPS valid
3539 bits, and so the KML export code thought there was no GPS data
3541 </p></li><li class="listitem"><p>
3542 The “Landed” tab was displaying all values in metric units,
3543 even when AltosUI was configured to display imperial
3544 units. Somehow I just missed this tab when doing the units stuff.
3545 </p></li><li class="listitem"><p>
3546 The “Descent” tab displays the range to the rocket, which is a
3547 combination of the over-the-ground distance to the rockets
3548 current latitude/longitude and the height of the rocket. As
3549 such, it's useful for knowing how far away the rocket is, but
3550 difficult to use when estimating where the rocket might
3551 eventually land. A new “Ground Distance” field has been added
3552 which displays the distance to a spot right underneath the
3554 </p></li><li class="listitem"><p>
3555 Sensor data wasn't being displayed for TeleMini flight
3556 computers in Monitor Idle mode, including things like battery
3557 voltage. The code that picked which kinds of data to fetch
3558 from the flight computer was missing a check for TeleMini when
3559 deciding whether to fetch the analog sensor data.
3560 </p></li></ul></div><p>
3561 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49775184"></a>Version 1.1</h2></div></div></div><p>
3562 Version 1.1 is a minor release. It provides a few new features in AltosUI
3563 and the AltOS firmware and fixes bugs.
3565 AltOS Firmware Changes
3566 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3567 Add apogee-lockout value. Overrides the apogee detection logic to
3568 prevent incorrect apogee charge firing.
3569 </p></li><li class="listitem"><p>
3570 Fix a bug where the data reported in telemetry packets was
3572 </p></li><li class="listitem"><p>
3573 Force the radio frequency to 434.550MHz when the debug clock
3574 pin is connected to ground at boot time. This provides a way
3575 to talk to a TeleMini which is configured to some unknown frequency.
3576 </p></li><li class="listitem"><p>
3577 Provide RSSI values for Monitor Idle mode. This makes it easy to check radio
3578 range without needing to go to flight mode.
3579 </p></li><li class="listitem"><p>
3580 Fix a bug which caused the old received telemetry packets to
3581 be retransmitted over the USB link when the radio was turned
3583 </p></li></ul></div><p>
3586 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3587 Fix a bug that caused GPS ready to happen too quickly. The
3588 software was using every telemetry packet to signal new GPS
3589 data, which caused GPS ready to be signalled after 10 packets
3590 instead of 10 GPS updates.
3591 </p></li><li class="listitem"><p>
3592 Fix Google Earth data export to work with recent versions. The
3593 google earth file loading code got a lot pickier, requiring
3594 some minor white space changes in the export code.
3595 </p></li><li class="listitem"><p>
3596 Make the look-n-feel configurable, providing a choice from
3597 the available options.
3598 </p></li><li class="listitem"><p>
3599 Add an 'Age' element to mark how long since a telemetry packet
3600 has been received. Useful to quickly gauge whether
3601 communications with the rocket are still active.
3602 </p></li><li class="listitem"><p>
3603 Add 'Configure Ground Station' dialog to set the radio
3604 frequency used by a particular TeleDongle without having to go
3605 through the flight monitor UI.
3606 </p></li><li class="listitem"><p>
3607 Add configuration for the new apogee-lockout value. A menu provides a list of
3608 reasonable values, or the value can be set by hand.
3609 </p></li><li class="listitem"><p>
3610 Changed how flight data are downloaded. Now there's an initial
3611 dialog asking which flights to download, and after that
3612 finishes, a second dialog comes up asking which flights to delete.
3613 </p></li><li class="listitem"><p>
3614 Re-compute time spent in each state for the flight graph; this
3615 figures out the actual boost and landing times instead of
3616 using the conservative values provide by the flight
3617 electronics. This improves the accuracy of the boost
3618 acceleration and main descent rate computations.
3619 </p></li><li class="listitem"><p>
3620 Make AltosUI run on Mac OS Lion. The default Java heap space
3621 was dramatically reduced for this release causing much of the
3622 UI to fail randomly. This most often affected the satellite
3623 mapping download and displays.
3624 </p></li><li class="listitem"><p>
3625 Change how data are displayed in the 'table' tab of the flight
3626 monitoring window. This eliminates entries duplicated from the
3627 header and adds both current altitude and pad altitude, which
3628 are useful in 'Monitor Idle' mode.
3629 </p></li><li class="listitem"><p>
3630 Add Imperial units mode to present data in feet instead of
3632 </p></li></ul></div><p>
3633 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49776688"></a>Version 1.0.1</h2></div></div></div><p>
3634 Version 1.0.1 is a major release, adding support for the TeleMini
3635 device and lots of new AltosUI features
3637 AltOS Firmware Changes
3638 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3639 Add TeleMini v1.0 support. Firmware images for TeleMini are
3640 included in AltOS releases.
3641 </p></li><li class="listitem"><p>
3642 Change telemetry to be encoded in multiple 32-byte packets. This
3643 enables support for TeleMini and other devices without requiring
3644 further updates to the TeleDongle firmware.
3645 </p></li><li class="listitem"><p>
3646 Support operation of TeleMetrum with the antenna pointing
3647 aft. Previous firmware versions required the antenna to be
3648 pointing upwards, now there is a configuration option allowing
3649 the antenna to point aft, to aid installation in some airframes.
3650 </p></li><li class="listitem"><p>
3651 Ability to disable telemetry. For airframes where an antenna
3652 just isn't possible, or where radio transmissions might cause
3653 trouble with other electronics, there's a configuration option
3654 to disable all telemetry. Note that the board will still
3655 enable the radio link in idle mode.
3656 </p></li><li class="listitem"><p>
3657 Arbitrary frequency selection. The radios in Altus Metrum
3658 devices can be programmed to a wide range of frequencies, so
3659 instead of limiting devices to 10 pre-selected 'channels', the
3660 new firmware allows the user to choose any frequency in the
3661 70cm band. Note that the RF matching circuit on the boards is
3662 tuned for around 435MHz, so frequencies far from that may
3663 reduce the available range.
3664 </p></li><li class="listitem"><p>
3665 Kalman-filter based flight-tracking. The model based sensor
3666 fusion approach of a Kalman filter means that AltOS now
3667 computes apogee much more accurately than before, generally
3668 within a fraction of a second. In addition, this approach
3669 allows the baro-only TeleMini device to correctly identify
3670 Mach transitions, avoiding the error-prone selection of a Mach
3672 </p></li></ul></div><p>
3675 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3676 Wait for altimeter when using packet mode. Instead of quicly
3677 timing out when trying to initialize a packet mode
3678 configuration connection, AltosUI now waits indefinitely for
3679 the remote device to appear, providing a cancel button should
3680 the user get bored. This is necessary as the TeleMini can only
3681 be placed in "Idle" mode if AltosUI is polling it.
3682 </p></li><li class="listitem"><p>
3683 Add main/apogee voltage graphs to the data plot. This provides
3684 a visual indication if the igniters fail before being fired.
3685 </p></li><li class="listitem"><p>
3686 Scan for altimeter devices by watching the defined telemetry
3687 frequencies. This avoids the problem of remembering what
3688 frequency a device was configured to use, which is especially
3689 important with TeleMini which does not include a USB connection.
3690 </p></li><li class="listitem"><p>
3691 Monitor altimeter state in "Idle" mode. This provides much of
3692 the information presented in the "Pad" dialog from the Monitor
3693 Flight command, monitoring the igniters, battery and GPS
3694 status withing requiring the flight computer to be armed and
3696 </p></li><li class="listitem"><p>
3697 Pre-load map images from home. For those launch sites which
3698 don't provide free Wi-Fi, this allows you to download the
3699 necessary satellite images given the location of the launch
3700 site. A list of known launch sites is maintained at
3701 altusmetrum.org which AltosUI downloads to populate a menu; if
3702 you've got a launch site not on that list, please send the
3703 name of it, latitude and longitude along with a link to the
3704 web site of the controlling club to the altusmetrum mailing list.
3705 </p></li><li class="listitem"><p>
3706 Flight statistics are now displayed in the Graph data
3707 window. These include max height/speed/accel, average descent
3708 rates and a few other bits of information. The Graph Data
3709 window can now be reached from the 'Landed' tab in the Monitor
3710 Flight window so you can immediately see the results of a
3712 </p></li></ul></div><p>
3713 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49778192"></a>Version 0.9.2</h2></div></div></div><p>
3714 Version 0.9.2 is an AltosUI bug-fix release, with no firmware changes.
3715 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3716 Fix plotting problems due to missing file in the Mac OS install image.
3717 </p></li><li class="listitem"><p>
3718 Always read whole eeprom blocks, mark empty records invalid, display parsing errors to user.
3719 </p></li><li class="listitem"><p>
3720 Add software version to Configure AltosUI dialog
3721 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49779696"></a>Version 0.9</h2></div></div></div><p>
3722 Version 0.9 adds a few new firmware features and accompanying
3723 AltosUI changes, along with new hardware support.
3724 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3725 Support for TeleMetrum v1.1 hardware. Sources for the flash
3726 memory part used in v1.0 dried up, so v1.1 uses a different part
3727 which required a new driver and support for explicit flight log
3729 </p></li><li class="listitem"><p>
3730 Multiple flight log support. This stores more than one flight
3731 log in the on-board flash memory. It also requires the user to
3732 explicitly erase flights so that you won't lose flight logs just
3733 because you fly the same board twice in one day.
3734 </p></li><li class="listitem"><p>
3735 Telemetry support for devices with serial number >=
3736 256. Previous versions used a telemetry packet format that
3737 provided only 8 bits for the device serial number. This change
3738 requires that both ends of the telemetry link be running the 0.9
3739 firmware or they will not communicate.
3740 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49781200"></a>Version 0.8</h2></div></div></div><p>
3741 Version 0.8 offers a major upgrade in the AltosUI
3742 interface. Significant new features include:
3743 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3744 Post-flight graphing tool. This lets you explore the behaviour
3745 of your rocket after flight with a scroll-able and zoom-able
3746 chart showing the altitude, speed and acceleration of the
3747 airframe along with events recorded by the flight computer. You
3748 can export graphs to PNG files, or print them directly.
3749 </p></li><li class="listitem"><p>
3750 Real-time moving map which overlays the in-progress flight on
3751 satellite imagery fetched from Google Maps. This lets you see in
3752 pictures where your rocket has landed, allowing you to plan
3753 recovery activities more accurately.
3754 </p></li><li class="listitem"><p>
3755 Wireless recovery system testing. Prep your rocket for flight
3756 and test fire the deployment charges to make sure things work as
3757 expected. All without threading wires through holes in your
3759 </p></li><li class="listitem"><p>
3760 Optimized flight status displays. Each flight state now has it's
3761 own custom 'tab' in the flight monitoring window so you can
3762 focus on the most important details. Pre-flight, the system
3763 shows a set of red/green status indicators for battery voltage,
3764 apogee/main igniter continutity and GPS reception. Wait until
3765 they're all green and your rocket is ready for flight. There are
3766 also tabs for ascent, descent and landing along with the
3767 original tabular view of the data.
3768 </p></li><li class="listitem"><p>
3769 Monitor multiple flights simultaneously. If you have more than
3770 one TeleDongle, you can monitor a flight with each one on the
3772 </p></li><li class="listitem"><p>
3773 Automatic flight monitoring at startup. Plug TeleDongle into the
3774 machine before starting AltosUI and it will automatically
3775 connect to it and prepare to monitor a flight.
3776 </p></li><li class="listitem"><p>
3777 Exports Google Earth flight tracks. Using the Keyhole Markup
3778 Language (.kml) file format, this provides a 3D view of your
3779 rocket flight through the Google Earth program.
3780 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp49782704"></a>Version 0.7.1</h2></div></div></div><p>
3781 Version 0.7.1 is the first release containing our new cross-platform Java-based user interface. AltosUI can:
3782 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3783 Receive and log telemetry from a connected TeleDongle
3784 device. All data received is saved to log files named with the
3785 current date and the connected rocket serial and flight
3786 numbers. There is no mode in which telemetry data will not be
3788 </p></li><li class="listitem"><p>
3789 Download logged data from TeleMetrum devices, either through a
3790 direct USB connection or over the air through a TeleDongle
3792 </p></li><li class="listitem"><p>
3793 Configure a TeleMetrum device, setting the radio channel,
3794 callsign, apogee delay and main deploy height. This can be done
3795 through either a USB connection or over a radio link via a
3797 </p></li><li class="listitem"><p>
3798 Replay a flight in real-time. This takes a saved telemetry log
3799 or eeprom download and replays it through the user interface so
3800 you can relive your favorite rocket flights.
3801 </p></li><li class="listitem"><p>
3802 Reprogram Altus Metrum devices. Using an Altus Metrum device
3803 connected via USB, another Altus Metrum device can be
3804 reprogrammed using the supplied programming cable between the
3806 </p></li><li class="listitem"><p>
3807 Export Flight data to a comma-separated-values file. This takes
3808 either telemetry or on-board flight data and generates data
3809 suitable for use in external applications. All data is exported
3810 using standard units so that no device-specific knowledge is
3811 needed to handle the data.
3812 </p></li><li class="listitem"><p>
3813 Speak to you during the flight. Instead of spending the flight
3814 hunched over your laptop looking at the screen, enjoy the view
3815 while the computer tells you what’s going on up there. During
3816 ascent, you hear the current flight state and altitude
3817 information. During descent, you get azimuth, elevation and
3818 range information to try and help you find your rocket in the
3819 air. Once on the ground, the direction and distance are
3821 </p></li></ul></div></div></div></div></body></html>
projects / web / altusmetrum / blob