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="idm6236096"></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="idp47882560"></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 1.3.1</td><td align="left">21 January 2014</td></tr><tr><td align="left" colspan="2">
8 Bug fixes for TeleMega and TeleMetrum v2.0 along with a few
10 </td></tr><tr><td align="left">Revision 1.3</td><td align="left">12 November 2013</td></tr><tr><td align="left" colspan="2">
11 Updated for software version 1.3. Version 1.3 adds support
12 for TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini
13 and fixes bugs in AltosUI and the AltOS firmware.
14 </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">
15 Updated for software version 1.2. Version 1.2 adds support
16 for TeleBT and AltosDroid. It also adds a few minor features
17 and fixes bugs in AltosUI and the AltOS firmware.
18 </td></tr><tr><td align="left">Revision 1.2</td><td align="left">18 April 2013</td></tr><tr><td align="left" colspan="2">
19 Updated for software version 1.2. Version 1.2 adds support
20 for MicroPeak and the MicroPeak USB interface.
21 </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">
22 Updated for software version 1.1.1 Version 1.1.1 fixes a few
23 bugs found in version 1.1.
24 </td></tr><tr><td align="left">Revision 1.1</td><td align="left">13 September 2012</td></tr><tr><td align="left" colspan="2">
25 Updated for software version 1.1. Version 1.1 has new
26 features but is otherwise compatible with version 1.0.
27 </td></tr><tr><td align="left">Revision 1.0</td><td align="left">24 August 2011</td></tr><tr><td align="left" colspan="2">
28 Updated for software version 1.0. Note that 1.0 represents a
29 telemetry format change, meaning both ends of a link
30 (TeleMetrum/TeleMini and TeleDongle) must be updated or
31 communications will fail.
32 </td></tr><tr><td align="left">Revision 0.9</td><td align="left">18 January 2011</td></tr><tr><td align="left" colspan="2">
33 Updated for software version 0.9. Note that 0.9 represents a
34 telemetry format change, meaning both ends of a link (TeleMetrum and
35 TeleDongle) must be updated or communications will fail.
36 </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="idp48972192"></a>Acknowledgments</h1></div></div></div><p>
37 Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing “The
38 Mere-Mortals Quick Start/Usage Guide to the Altus Metrum Starter
39 Kit” which formed the basis of the original Getting Started chapter
40 in this manual. Bob was one of our first customers for a production
41 TeleMetrum, and his continued enthusiasm and contributions
42 are immensely gratifying and highly appreciated!
44 And thanks to Anthony (AJ) Towns for major contributions including
45 the AltosUI graphing and site map code and associated documentation.
46 Free software means that our customers and friends can become our
47 collaborators, and we certainly appreciate this level of
50 Have fun using these products, and we hope to meet all of you
51 out on the rocket flight line somewhere.
52 </p><div class="literallayout"><p><br>
53 Bdale Garbee, KB0G<br>
54 NAR #87103, TRA #12201<br>
56 Keith Packard, KD7SQG<br>
57 NAR #88757, TRA #12200<br>
59 </p></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="chapter"><a href="#idp48053984">1. Introduction and Overview</a></span></dt><dt><span class="chapter"><a href="#idp48061744">2. Getting Started</a></span></dt><dt><span class="chapter"><a href="#idp47890336">3. Handling Precautions</a></span></dt><dt><span class="chapter"><a href="#idp47895824">4. Altus Metrum Hardware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp47896496">1. Overview</a></span></dt><dt><span class="section"><a href="#idp53909808">2. TeleMetrum</a></span></dt><dt><span class="section"><a href="#idp53914976">3. TeleMini</a></span></dt><dt><span class="section"><a href="#idp53923600">4. EasyMini</a></span></dt><dt><span class="section"><a href="#idp53927712">5. TeleMega</a></span></dt><dt><span class="section"><a href="#idp53931936">6. Flight Data Recording</a></span></dt><dt><span class="section"><a href="#idp53961856">7. Installation</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp53968624">5. System Operation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp53969296">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp53977296">2. GPS </a></span></dt><dt><span class="section"><a href="#idp53979824">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp54060432">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp54063184">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp54067872">6. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54069616">6.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp54071664">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp54074256">6.3. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp54075952">6.4. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp54078096">6.5. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp54080208">6.6. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp54081904">6.7. Configurable Pyro Channels</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="#idp54104384">6. AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54108000">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54120720">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp54136352">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp54141808">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp54148672">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp54155520">1.5. Table</a></span></dt><dt><span class="section"><a href="#idp54159104">1.6. Site Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54164768">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp54168720">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp54170752">4. Graph Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54173136">4.1. Flight Graph</a></span></dt><dt><span class="section"><a href="#idp54177584">4.2. Configure Graph</a></span></dt><dt><span class="section"><a href="#idp54181248">4.3. Flight Statistics</a></span></dt><dt><span class="section"><a href="#idp54184768">4.4. Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54188624">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54190192">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp54192544">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54194032">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54206336">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp54208304">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp54209920">6.3. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp54211424">6.4. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp54213072">6.5. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp54214368">6.6. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp54215872">6.7. Callsign</a></span></dt><dt><span class="section"><a href="#idp54217184">6.8. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp54218624">6.9. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp54225616">6.10. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp54230832">6.11. Configure Pyro Channels</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54236640">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54240144">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp54245168">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp54247168">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp54249408">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp54250912">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp54252192">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp54253696">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54255328">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54266448">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp54268016">8.2. Radio Calibration</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54269648">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp54271280">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp54276912">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp54280768">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp54286464">13. Monitor Idle</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp54288560">7. AltosDroid</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54290944">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp54292880">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp54294880">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp54296336">4. AltosDroid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54297648">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54311200">5. Downloading Flight Logs</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp54312864">8. Using Altus Metrum Products</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54313504">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp54315408">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp54317872">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp54331184">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp54333728">5. Future Plans</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp54338112">9. Altimeter Installation Recommendations</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54339568">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp54344400">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp54349968">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp54354752">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp54362320">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp54365120">6. Ground Testing</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp54368288">10. Updating Device Firmware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54372304">1.
60 Updating TeleMega, TeleMetrum v2 or EasyMini Firmware
61 </a></span></dt><dd><dl><dt><span class="section"><a href="#idp54381120">1.1. Recovering From Self-Flashing Failure</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54390096">2. Pair Programming</a></span></dt><dt><span class="section"><a href="#idp54391536">3. Updating TeleMetrum v1.x Firmware</a></span></dt><dt><span class="section"><a href="#idp54404576">4. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp54417968">5. Updating TeleDongle Firmware</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp54434512">11. Hardware Specifications</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54435152">1.
62 TeleMega Specifications
63 </a></span></dt><dt><span class="section"><a href="#idp54446496">2.
64 TeleMetrum v2 Specifications
65 </a></span></dt><dt><span class="section"><a href="#idp54457056">3. TeleMetrum v1 Specifications</a></span></dt><dt><span class="section"><a href="#idp54467616">4.
66 TeleMini v2.0 Specifications
67 </a></span></dt><dt><span class="section"><a href="#idp54476448">5.
68 TeleMini v1.0 Specifications
69 </a></span></dt><dt><span class="section"><a href="#idp54485248">6.
70 EasyMini Specifications
71 </a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp54493360">12. FAQ</a></span></dt><dt><span class="appendix"><a href="#idp54502208">A. Notes for Older Software</a></span></dt><dt><span class="appendix"><a href="#idp54526032">B. Drill Templates</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54527200">1. TeleMega template</a></span></dt><dt><span class="section"><a href="#idp54543168">2. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp54546832">3. TeleMini v2/EasyMini template</a></span></dt><dt><span class="section"><a href="#idp54550512">4. TeleMini v1 template</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp54554304">C. Calibration</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54555856">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp54561136">2. TeleMetrum and TeleMega Accelerometers</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp54567264">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="#idp47897552">Altus Metrum Electronics</a></dt><dt>4.2. <a href="#idp53870912">Altus Metrum Boards</a></dt><dt>4.3. <a href="#idp53933376">Data Storage on Altus Metrum altimeters</a></dt><dt>5.1. <a href="#idp50990144">AltOS Modes</a></dt><dt>5.2. <a href="#idp54003920">Pad/Idle Indications</a></dt></dl></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp48053984"></a>Chapter 1. Introduction and Overview</h1></div></div></div><p>
72 Welcome to the Altus Metrum community! Our circuits and software reflect
73 our passion for both hobby rocketry and Free Software. We hope their
74 capabilities and performance will delight you in every way, but by
75 releasing all of our hardware and software designs under open licenses,
76 we also hope to empower you to take as active a role in our collective
79 The first device created for our community was TeleMetrum, a dual
80 deploy altimeter with fully integrated GPS and radio telemetry
81 as standard features, and a “companion interface” that will
82 support optional capabilities in the future. The latest version
83 of TeleMetrum, v2.0, has all of the same features but with
84 improved sensors and radio to offer increased performance.
86 Our second device was TeleMini, a dual deploy altimeter with
87 radio telemetry and radio direction finding. The first version
88 of this device was only 13mm by 38mm (½ inch by 1½ inches) and
89 could fit easily in an 18mm air-frame. The latest version, v2.0,
90 includes a beeper, USB data download and extended on-board
91 flight logging, along with an improved barometric sensor.
93 TeleMega is our most sophisticated device, including six pyro
94 channels (four of which are fully programmable), integrated GPS,
95 integrated gyroscopes for staging/air-start inhibit and high
96 performance telemetry.
98 EasyMini is a dual-deploy altimeter with logging and built-in
101 TeleDongle was our first ground station, providing a USB to RF
102 interfaces for communicating with the altimeters. Combined with
103 your choice of antenna and notebook computer, TeleDongle and our
104 associated user interface software form a complete ground
105 station capable of logging and displaying in-flight telemetry,
106 aiding rocket recovery, then processing and archiving flight
107 data for analysis and review.
109 For a slightly more portable ground station experience that also
110 provides direct rocket recovery support, TeleBT offers flight
111 monitoring and data logging using a Bluetooth™ connection between
112 the receiver and an Android device that has the AltosDroid
113 application installed from the Google Play store.
115 More products will be added to the Altus Metrum family over time, and
116 we currently envision that this will be a single, comprehensive manual
117 for the entire product family.
118 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp48061744"></a>Chapter 2. Getting Started</h1></div></div></div><p>
119 The first thing to do after you check the inventory of parts in your
120 “starter kit” is to charge the battery.
122 For TeleMetrum and TeleMega, the battery can be charged by plugging it into the
123 corresponding socket of the device and then using the USB
124 cable to plug the flight computer into your computer's USB socket. The
125 on-board circuitry will charge the battery whenever it is plugged
126 in, because the on-off switch does NOT control the
129 On TeleMetrum v1 boards, when the GPS chip is initially
130 searching for satellites, TeleMetrum will consume more current
131 than it pulls from the USB port, so the battery must be
132 attached in order to get satellite lock. Once GPS is locked,
133 the current consumption goes back down enough to enable charging
134 while running. So it's a good idea to fully charge the battery
135 as your first item of business so there is no issue getting and
136 maintaining satellite lock. The yellow charge indicator led
137 will go out when the battery is nearly full and the charger goes
138 to trickle charge. It can take several hours to fully recharge a
139 deeply discharged battery.
141 TeleMetrum v2.0 and TeleMega use a higher power battery charger,
142 allowing them to charge the battery while running the board at
143 maximum power. When the battery is charging, or when the board
144 is consuming a lot of power, the red LED will be lit. When the
145 battery is fully charged, the green LED will be lit. When the
146 battery is damaged or missing, both LEDs will be lit, which
149 The Lithium Polymer TeleMini and EasyMini battery can be charged by
150 disconnecting it from the board and plugging it into a
151 standalone battery charger such as the LipoCharger product
152 included in TeleMini Starter Kits, and connecting that via a USB
153 cable to a laptop or other USB power source.
155 You can also choose to use another battery with TeleMini v2.0
156 and EasyMini, anything supplying between 4 and 12 volts should
157 work fine (like a standard 9V battery), but if you are planning
158 to fire pyro charges, ground testing is required to verify that
159 the battery supplies enough current to fire your chosen e-matches.
161 The other active device in the starter kit is the TeleDongle USB to
162 RF interface. If you plug it in to your Mac or Linux computer it should
163 “just work”, showing up as a serial port device. Windows systems need
164 driver information that is part of the AltOS download to know that the
165 existing USB modem driver will work. We therefore recommend installing
166 our software before plugging in TeleDongle if you are using a Windows
167 computer. If you are using an older version of Linux and are having
168 problems, try moving to a fresher kernel (2.6.33 or newer).
170 Next you should obtain and install the AltOS software. The AltOS
171 distribution includes the AltosUI ground station program, current
173 images for all of the hardware, and a number of standalone
174 utilities that are rarely needed. Pre-built binary packages are
175 available for Linux, Microsoft Windows, and recent MacOSX
176 versions. Full source code and build instructions are also
177 available. The latest version may always be downloaded from
178 <a class="ulink" href="http://altusmetrum.org/AltOS" target="_top">http://altusmetrum.org/AltOS</a>.
180 If you're using a TeleBT instead of the TeleDongle, you'll want to
181 install the AltosDroid application from the Google Play store on an
182 Android device. You don't need a data plan to use AltosDroid, but
183 without network access, the Map view will be less useful as it
184 won't contain any map data. You can also use TeleBT connected
185 over USB with your laptop computer; it acts exactly like a
186 TeleDongle. Anywhere this manual talks about TeleDongle, you can
187 also read that as 'and TeleBT when connected via USB'.
188 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp47890336"></a>Chapter 3. Handling Precautions</h1></div></div></div><p>
189 All Altus Metrum products are sophisticated electronic devices.
190 When handled gently and properly installed in an air-frame, they
191 will deliver impressive results. However, as with all electronic
192 devices, there are some precautions you must take.
194 The Lithium Polymer rechargeable batteries have an
195 extraordinary power density. This is great because we can fly with
196 much less battery mass than if we used alkaline batteries or previous
197 generation rechargeable batteries... but if they are punctured
198 or their leads are allowed to short, they can and will release their
200 Thus we recommend that you take some care when handling our batteries
201 and consider giving them some extra protection in your air-frame. We
202 often wrap them in suitable scraps of closed-cell packing foam before
203 strapping them down, for example.
205 The barometric sensors used on all of our flight computers are
206 sensitive to sunlight. In normal mounting situations, the baro sensor
207 and all of the other surface mount components
208 are “down” towards whatever the underlying mounting surface is, so
209 this is not normally a problem. Please consider this when designing an
210 installation in an air-frame with a see-through plastic payload bay. It
211 is particularly important to
212 consider this with TeleMini v1.0, both because the baro sensor is on the
213 “top” of the board, and because many model rockets with payload bays
214 use clear plastic for the payload bay! Replacing these with an opaque
215 cardboard tube, painting them, or wrapping them with a layer of masking
216 tape are all reasonable approaches to keep the sensor out of direct
219 The barometric sensor sampling port must be able to “breathe”,
220 both by not being covered by foam or tape or other materials that might
221 directly block the hole on the top of the sensor, and also by having a
222 suitable static vent to outside air.
224 As with all other rocketry electronics, Altus Metrum altimeters must
225 be protected from exposure to corrosive motor exhaust and ejection
227 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp47895824"></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="#idp47896496">1. Overview</a></span></dt><dt><span class="section"><a href="#idp53909808">2. TeleMetrum</a></span></dt><dt><span class="section"><a href="#idp53914976">3. TeleMini</a></span></dt><dt><span class="section"><a href="#idp53923600">4. EasyMini</a></span></dt><dt><span class="section"><a href="#idp53927712">5. TeleMega</a></span></dt><dt><span class="section"><a href="#idp53931936">6. Flight Data Recording</a></span></dt><dt><span class="section"><a href="#idp53961856">7. Installation</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp47896496"></a>1. Overview</h2></div></div></div><p>
228 Here's the full set of Altus Metrum products, both in
229 production and retired.
230 </p><div class="table"><a name="idp47897552"></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></tbody></table></div></div><br class="table-break"><div class="table"><a name="idp53870912"></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>
236 </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>
240 </p></td><td align="center"><p>
243 </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>
248 </p></td><td align="center"><p>
253 </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>
257 </p></td><td align="center"><p>
262 </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>
268 </p></td><td align="center"><p>
274 </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></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="idp53909808"></a>2. 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>
275 TeleMetrum is a 1 inch by 2¾ inch circuit board. It was designed to
276 fit inside coupler for 29mm air-frame tubing, but using it in a tube that
277 small in diameter may require some creativity in mounting and wiring
278 to succeed! The presence of an accelerometer means TeleMetrum should
279 be aligned along the flight axis of the airframe, and by default the ¼
280 wave UHF wire antenna should be on the nose-cone end of the board. The
281 antenna wire is about 7 inches long, and wiring for a power switch and
282 the e-matches for apogee and main ejection charges depart from the
283 fin can end of the board, meaning an ideal “simple” avionics
284 bay for TeleMetrum should have at least 10 inches of interior length.
285 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp53914976"></a>3. TeleMini</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>
286 TeleMini v1.0 is ½ inches by 1½ inches. It was
287 designed to fit inside an 18mm air-frame tube, but using it in
288 a tube that small in diameter may require some creativity in
289 mounting and wiring to succeed! Since there is no
290 accelerometer, TeleMini can be mounted in any convenient
291 orientation. The default ¼ wave UHF wire antenna attached to
292 the center of one end of the board is about 7 inches long. Two
293 wires for the power switch are connected to holes in the
294 middle of the board. Screw terminals for the e-matches for
295 apogee and main ejection charges depart from the other end of
296 the board, meaning an ideal “simple” avionics bay for TeleMini
297 should have at least 9 inches of interior length.
298 </p><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>
299 TeleMini v2.0 is 0.8 inches by 1½ inches. It adds more
300 on-board data logging memory, a built-in USB connector and
301 screw terminals for the battery and power switch. The larger
302 board fits in a 24mm coupler. There's also a battery connector
303 for a LiPo battery if you want to use one of those.
304 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp53923600"></a>4. 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>
305 EasyMini is built on a 0.8 inch by 1½ inch circuit board. It's
306 designed to fit in a 24mm coupler tube. The connectors and
307 screw terminals match TeleMini v2.0, so you can easily swap between
308 EasyMini and TeleMini.
309 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp53927712"></a>5. 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>
310 TeleMega is a 1¼ inch by 3¼ inch circuit board. It was
311 designed to easily fit in a 38mm coupler. Like TeleMetrum,
312 TeleMega has an accelerometer and so it must be mounted so that
313 the board is aligned with the flight axis. It can be mounted
314 either antenna up or down.
315 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp53931936"></a>6. Flight Data Recording</h2></div></div></div><p>
316 Each flight computer logs data at 100 samples per second
317 during ascent and 10 samples per second during descent, except
318 for TeleMini v1.0, which records ascent at 10 samples per
319 second and descent at 1 sample per second. Data are logged to
320 an on-board flash memory part, which can be partitioned into
321 several equal-sized blocks, one for each flight.
322 </p><div class="table"><a name="idp53933376"></a><p class="title"><b>Table 4.3. 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></tbody></table></div></div><br class="table-break"><p>
323 The on-board flash is partitioned into separate flight logs,
324 each of a fixed maximum size. Increase the maximum size of
325 each log and you reduce the number of flights that can be
326 stored. Decrease the size and you can store more flights.
328 Configuration data is also stored in the flash memory on
329 TeleMetrum v1.x, TeleMini and EasyMini. This consumes 64kB
330 of flash space. This configuration space is not available
331 for storing flight log data. TeleMetrum v2.0 and TeleMega
332 store configuration data in a bit of eeprom available within
333 the processor chip, leaving that space available in flash for
336 To compute the amount of space needed for a single flight, you
337 can multiply the expected ascent time (in seconds) by 100
338 times bytes-per-sample, multiply the expected descent time (in
339 seconds) by 10 times the bytes per sample and add the two
340 together. That will slightly under-estimate the storage (in
341 bytes) needed for the flight. For instance, a TeleMetrum v2.0 flight spending
342 20 seconds in ascent and 150 seconds in descent will take
343 about (20 * 1600) + (150 * 160) = 56000 bytes of storage. You
344 could store dozens of these flights in the on-board flash.
346 The default size allows for several flights on each flight
347 computer, except for TeleMini v1.0, which only holds data for a
348 single flight. You can adjust the size.
350 Altus Metrum flight computers will not overwrite existing
351 flight data, so be sure to download flight data and erase it
352 from the flight computer before it fills up. The flight
353 computer will still successfully control the flight even if it
354 cannot log data, so the only thing you will lose is the data.
355 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp53961856"></a>7. Installation</h2></div></div></div><p>
356 A typical installation involves attaching
357 only a suitable battery, a single pole switch for
358 power on/off, and two pairs of wires connecting e-matches for the
359 apogee and main ejection charges. All Altus Metrum products are
360 designed for use with single-cell batteries with 3.7 volts
361 nominal. TeleMini v2.0 and EasyMini may also be used with other
362 batteries as long as they supply between 4 and 12 volts.
364 The battery connectors are a standard 2-pin JST connector and
365 match batteries sold by Spark Fun. These batteries are
366 single-cell Lithium Polymer batteries that nominally provide 3.7
367 volts. Other vendors sell similar batteries for RC aircraft
368 using mating connectors, however the polarity for those is
369 generally reversed from the batteries used by Altus Metrum
370 products. In particular, the Tenergy batteries supplied for use
371 in Featherweight flight computers are not compatible with Altus
372 Metrum flight computers or battery chargers. <span class="emphasis"><em>Check
373 polarity and voltage before connecting any battery not purchased
374 from Altus Metrum or Spark Fun.</em></span>
376 By default, we use the unregulated output of the battery directly
377 to fire ejection charges. This works marvelously with standard
378 low-current e-matches like the J-Tek from MJG Technologies, and with
379 Quest Q2G2 igniters. However, if you want or need to use a separate
380 pyro battery, check out the “External Pyro Battery” section in this
381 manual for instructions on how to wire that up. The altimeters are
382 designed to work with an external pyro battery of no more than 15 volts.
385 Ejection charges are wired directly to the screw terminal block
386 at the aft end of the altimeter. You'll need a very small straight
387 blade screwdriver for these screws, such as you might find in a
388 jeweler's screwdriver set.
390 Except for TeleMini v1.0, the flight computers also use the
391 screw terminal block for the power switch leads. On TeleMini v1.0,
392 the power switch leads are soldered directly to the board and
393 can be connected directly to a switch.
395 For most air-frames, the integrated antennas are more than
396 adequate. However, if you are installing in a carbon-fiber or
397 metal electronics bay which is opaque to RF signals, you may need to
398 use off-board external antennas instead. In this case, you can
399 replace the stock UHF antenna wire with an edge-launched SMA connector,
400 and, on TeleMetrum v1, you can unplug the integrated GPS
401 antenna and select an appropriate off-board GPS antenna with
402 cable terminating in a U.FL connector.
403 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp53968624"></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="#idp53969296">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp53977296">2. GPS </a></span></dt><dt><span class="section"><a href="#idp53979824">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp54060432">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp54063184">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp54067872">6. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54069616">6.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp54071664">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp54074256">6.3. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp54075952">6.4. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp54078096">6.5. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp54080208">6.6. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp54081904">6.7. 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="idp53969296"></a>1. Firmware Modes </h2></div></div></div><p>
404 The AltOS firmware build for the altimeters has two
405 fundamental modes, “idle” and “flight”. Which of these modes
406 the firmware operates in is determined at start up time. For
407 TeleMetrum and TeleMega, which have accelerometers, the mode is
408 controlled by the orientation of the
409 rocket (well, actually the board, of course...) at the time
410 power is switched on. If the rocket is “nose up”, then
411 the flight computer assumes it's on a rail or rod being prepared for
412 launch, so the firmware chooses flight mode. However, if the
413 rocket is more or less horizontal, the firmware instead enters
414 idle mode. Since TeleMini v2.0 and EasyMini don't have an
415 accelerometer we can use to determine orientation, “idle” mode
416 is selected if the board is connected via USB to a computer,
417 otherwise the board enters “flight” mode. TeleMini v1.0
418 selects “idle” mode if it receives a command packet within the
419 first five seconds of operation.
421 At power on, you will hear three beeps or see three flashes
422 (“S” in Morse code for start up) and then a pause while
423 the altimeter completes initialization and self test, and decides
424 which mode to enter next.
426 Here's a short summary of all of the modes and the beeping (or
427 flashing, in the case of TeleMini v1) that accompanies each
428 mode. In the description of the beeping pattern, “dit” means a
429 short beep while "dah" means a long beep (three times as
430 long). “Brap” means a long dissonant tone.
431 </p><div class="table"><a name="idp50990144"></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">dit dit dit</td><td align="center">
433 Calibrating sensors, detecting orientation.
435 </td></tr><tr><td align="center">Idle</td><td align="center">I</td><td align="center">dit dit</td><td align="center">
437 Ready to accept commands over USB or radio link.
439 </td></tr><tr><td align="center">Pad</td><td align="center">P</td><td align="center">dit dah dah dit</td><td align="center">
441 Waiting for launch. Not listening for commands.
443 </td></tr><tr><td align="center">Boost</td><td align="center">B</td><td align="center">dah dit dit dit</td><td align="center">
445 Accelerating upwards.
447 </td></tr><tr><td align="center">Fast</td><td align="center">F</td><td align="center">dit dit dah dit</td><td align="center">
449 Decellerating, but moving faster than 200m/s.
451 </td></tr><tr><td align="center">Coast</td><td align="center">C</td><td align="center">dah dit dah dit</td><td align="center">
453 Decellerating, moving slower than 200m/s
455 </td></tr><tr><td align="center">Drogue</td><td align="center">D</td><td align="center">dah dit dit</td><td align="center">
457 Descending after apogee. Above main height.
459 </td></tr><tr><td align="center">Main</td><td align="center">M</td><td align="center">dah dah</td><td align="center">
461 Descending. Below main height.
463 </td></tr><tr><td align="center">Landed</td><td align="center">L</td><td align="center">dit dah dit dit</td><td align="center">
465 Stable altitude for at least ten seconds.
467 </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">
469 Error detected during sensor calibration.
471 </td></tr></tbody></table></div></div><p><br class="table-break">
473 In flight or “pad” mode, the altimeter engages the flight
474 state machine, goes into transmit-only mode to send telemetry,
475 and waits for launch to be detected. Flight mode is indicated
476 by an “di-dah-dah-dit” (“P” for pad) on the beeper or lights,
477 followed by beeps or flashes indicating the state of the
478 pyrotechnic igniter continuity. One beep/flash indicates
479 apogee continuity, two beeps/flashes indicate main continuity,
480 three beeps/flashes indicate both apogee and main continuity,
481 and one longer “brap” sound which is made by rapidly
482 alternating between two tones indicates no continuity. For a
483 dual deploy flight, make sure you're getting three beeps or
484 flashes before launching! For apogee-only or motor eject
485 flights, do what makes sense.
487 If idle mode is entered, you will hear an audible “di-dit” or
488 see two short flashes (“I” for idle), and the flight state
489 machine is disengaged, thus no ejection charges will fire.
490 The altimeters also listen for the radio link when in idle
491 mode for requests sent via TeleDongle. Commands can be issued
492 in idle mode over either USB or the radio link
493 equivalently. TeleMini v1.0 only has the radio link. Idle
494 mode is useful for configuring the altimeter, for extracting
495 data from the on-board storage chip after flight, and for
496 ground testing pyro charges.
498 In “Idle” and “Pad” modes, once the mode indication
499 beeps/flashes and continuity indication has been sent, if
500 there is no space available to log the flight in on-board
501 memory, the flight computer will emit a warbling tone (much
502 slower than the “no continuity tone”)
504 Here's a summary of all of the “pad” and “idle” mode indications.
505 </p><div class="table"><a name="idp54003920"></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">
507 No continuity detected on either apogee or main
510 </td></tr><tr><td align="center">Apogee</td><td align="center">dit</td><td align="center">
512 Continuity detected only on apogee igniter.
514 </td></tr><tr><td align="center">Main</td><td align="center">dit dit</td><td align="center">
516 Continuity detected only on main igniter.
518 </td></tr><tr><td align="center">Both</td><td align="center">dit dit dit</td><td align="center">
520 Continuity detected on both igniters.
522 </td></tr><tr><td align="center">Storage Full</td><td align="center">warble</td><td align="center">
524 On-board data logging storage is full. This will
525 not prevent the flight computer from safely
526 controlling the flight or transmitting telemetry
527 signals, but no record of the flight will be
528 stored in on-board flash.
530 </td></tr></tbody></table></div></div><p><br class="table-break">
532 Once landed, the flight computer will signal that by emitting
533 the “Landed” sound described above, after which it will beep
534 out the apogee height (in meters). Each digit is represented
535 by a sequence of short “dit” beeps, with a pause between
536 digits. A zero digit is represented with one long “dah”
537 beep. The flight computer will continue to report landed mode
538 and beep out the maximum height until turned off.
540 One “neat trick” of particular value when TeleMetrum or TeleMega are used with
541 very large air-frames, is that you can power the board up while the
542 rocket is horizontal, such that it comes up in idle mode. Then you can
543 raise the air-frame to launch position, and issue a 'reset' command
544 via TeleDongle over the radio link to cause the altimeter to reboot and
545 come up in flight mode. This is much safer than standing on the top
546 step of a rickety step-ladder or hanging off the side of a launch
547 tower with a screw-driver trying to turn on your avionics before
550 TeleMini v1.0 is configured solely via the radio link. Of course, that
551 means you need to know the TeleMini radio configuration values
552 or you won't be able to communicate with it. For situations
553 when you don't have the radio configuration values, TeleMini v1.0
554 offers an 'emergency recovery' mode. In this mode, TeleMini is
555 configured as follows:
556 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
557 Sets the radio frequency to 434.550MHz
558 </p></li><li class="listitem"><p>
559 Sets the radio calibration back to the factory value.
560 </p></li><li class="listitem"><p>
561 Sets the callsign to N0CALL
562 </p></li><li class="listitem"><p>
563 Does not go to 'pad' mode after five seconds.
564 </p></li></ul></div><p>
566 To get into 'emergency recovery' mode, first find the row of
567 four small holes opposite the switch wiring. Using a short
568 piece of small gauge wire, connect the outer two holes
569 together, then power TeleMini up. Once the red LED is lit,
570 disconnect the wire and the board should signal that it's in
571 'idle' mode after the initial five second startup period.
572 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp53977296"></a>2. GPS </h2></div></div></div><p>
573 TeleMetrum and TeleMega include a complete GPS receiver. A
574 complete explanation of how GPS works is beyond the scope of
575 this manual, but the bottom line is that the GPS receiver
576 needs to lock onto at least four satellites to obtain a solid
577 3 dimensional position fix and know what time it is.
579 The flight computers provide backup power to the GPS chip any time a
580 battery is connected. This allows the receiver to “warm start” on
581 the launch rail much faster than if every power-on were a GPS
582 “cold start”. In typical operations, powering up
583 on the flight line in idle mode while performing final air-frame
584 preparation will be sufficient to allow the GPS receiver to cold
585 start and acquire lock. Then the board can be powered down during
586 RSO review and installation on a launch rod or rail. When the board
587 is turned back on, the GPS system should lock very quickly, typically
588 long before igniter installation and return to the flight line are
590 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp53979824"></a>3. Controlling An Altimeter Over The Radio Link</h2></div></div></div><p>
591 One of the unique features of the Altus Metrum system is the
592 ability to create a two way command link between TeleDongle
593 and an altimeter using the digital radio transceivers
594 built into each device. This allows you to interact with the
595 altimeter from afar, as if it were directly connected to the
598 Any operation which can be performed with a flight computer can
599 either be done with the device directly connected to the
600 computer via the USB cable, or through the radio
601 link. TeleMini v1.0 doesn't provide a USB connector and so it is
602 always communicated with over radio. Select the appropriate
603 TeleDongle device when the list of devices is presented and
604 AltosUI will interact with an altimeter over the radio link.
606 One oddity in the current interface is how AltosUI selects the
607 frequency for radio communications. Instead of providing
608 an interface to specifically configure the frequency, it uses
609 whatever frequency was most recently selected for the target
610 TeleDongle device in Monitor Flight mode. If you haven't ever
611 used that mode with the TeleDongle in question, select the
612 Monitor Flight button from the top level UI, and pick the
613 appropriate TeleDongle device. Once the flight monitoring
614 window is open, select the desired frequency and then close it
615 down again. All radio communications will now use that frequency.
616 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
617 Save Flight Data—Recover flight data from the rocket without
619 </p></li><li class="listitem"><p>
620 Configure altimeter apogee delays, main deploy heights
621 and additional pyro event conditions
622 to respond to changing launch conditions. You can also
623 'reboot' the altimeter. Use this to remotely enable the
624 flight computer by turning TeleMetrum or TeleMega on in “idle” mode,
625 then once the air-frame is oriented for launch, you can
626 reboot the altimeter and have it restart in pad mode
627 without having to climb the scary ladder.
628 </p></li><li class="listitem"><p>
629 Fire Igniters—Test your deployment charges without snaking
630 wires out through holes in the air-frame. Simply assemble the
631 rocket as if for flight with the apogee and main charges
632 loaded, then remotely command the altimeter to fire the
634 </p></li></ul></div><p>
635 Operation over the radio link for configuring an altimeter, ground
636 testing igniters, and so forth uses the same RF frequencies as flight
637 telemetry. To configure the desired TeleDongle frequency, select
638 the monitor flight tab, then use the frequency selector and
639 close the window before performing other desired radio operations.
641 The flight computers only enable radio commanding in 'idle' mode.
642 TeleMetrum and TeleMega use the accelerometer to detect which orientation they
643 start up in, so make sure you have the flight computer lying horizontally when you turn
644 it on. Otherwise, it will start in 'pad' mode ready for
645 flight, and will not be listening for command packets from TeleDongle.
647 TeleMini listens for a command packet for five seconds after
648 first being turned on, if it doesn't hear anything, it enters
649 'pad' mode, ready for flight and will no longer listen for
650 command packets. The easiest way to connect to TeleMini is to
651 initiate the command and select the TeleDongle device. At this
652 point, the TeleDongle will be attempting to communicate with
653 the TeleMini. Now turn TeleMini on, and it should immediately
654 start communicating with the TeleDongle and the desired
655 operation can be performed.
657 You can monitor the operation of the radio link by watching the
658 lights on the devices. The red LED will flash each time a packet
659 is transmitted, while the green LED will light up on TeleDongle when
660 it is waiting to receive a packet from the altimeter.
661 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54060432"></a>4. Ground Testing </h2></div></div></div><p>
662 An important aspect of preparing a rocket using electronic deployment
663 for flight is ground testing the recovery system. Thanks
664 to the bi-directional radio link central to the Altus Metrum system,
665 this can be accomplished in a TeleMega, TeleMetrum or TeleMini equipped rocket
666 with less work than you may be accustomed to with other systems. It
669 Just prep the rocket for flight, then power up the altimeter
670 in “idle” mode (placing air-frame horizontal for TeleMetrum or TeleMega, or
671 selecting the Configure Altimeter tab for TeleMini). This will cause
672 the firmware to go into “idle” mode, in which the normal flight
673 state machine is disabled and charges will not fire without
674 manual command. You can now command the altimeter to fire the apogee
675 or main charges from a safe distance using your computer and
676 TeleDongle and the Fire Igniter tab to complete ejection testing.
677 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54063184"></a>5. Radio Link </h2></div></div></div><p>
678 Our flight computers all incorporate an RF transceiver, but
679 it's not a full duplex system... each end can only be transmitting or
680 receiving at any given moment. So we had to decide how to manage the
683 By design, the altimeter firmware listens for the radio link when
684 it's in “idle mode”, which
685 allows us to use the radio link to configure the rocket, do things like
686 ejection tests, and extract data after a flight without having to
687 crack open the air-frame. However, when the board is in “flight
688 mode”, the altimeter only
689 transmits and doesn't listen at all. That's because we want to put
690 ultimate priority on event detection and getting telemetry out of
692 the radio in case the rocket crashes and we aren't able to extract
695 We don't generally use a 'normal packet radio' mode like APRS
696 because they're just too inefficient. The GFSK modulation we
697 use is FSK with the base-band pulses passed through a Gaussian
698 filter before they go into the modulator to limit the
699 transmitted bandwidth. When combined with forward error
700 correction and interleaving, this allows us to have a very
701 robust 19.2 kilobit data link with only 10-40 milliwatts of
702 transmit power, a whip antenna in the rocket, and a hand-held
703 Yagi on the ground. We've had flights to above 21k feet AGL
704 with great reception, and calculations suggest we should be
705 good to well over 40k feet AGL with a 5-element yagi on the
706 ground with our 10mW units and over 100k feet AGL with the
707 40mW devices. We hope to fly boards to higher altitudes over
708 time, and would of course appreciate customer feedback on
709 performance in higher altitude flights!
711 TeleMetrum v2.0 and TeleMega can send APRS if desired, and the
712 interval between APRS packets can be configured. As each APRS
713 packet takes a full second to transmit, we recommend an
714 interval of at least 5 seconds to avoid consuming too much
715 battery power or radio channel bandwidth.
716 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54067872"></a>6. Configurable Parameters</h2></div></div></div><p>
717 Configuring an Altus Metrum altimeter for flight is very
718 simple. Even on our baro-only TeleMini and EasyMini boards, the use of a Kalman
719 filter means there is no need to set a “mach delay”. The few
720 configurable parameters can all be set using AltosUI over USB or
721 or radio link via TeleDongle.
722 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54069616"></a>6.1. Radio Frequency</h3></div></div></div><p>
723 Altus Metrum boards support radio frequencies in the 70cm
724 band. By default, the configuration interface provides a
725 list of 10 “standard” frequencies in 100kHz channels starting at
726 434.550MHz. However, the firmware supports use of
727 any 50kHz multiple within the 70cm band. At any given
728 launch, we highly recommend coordinating when and by whom each
729 frequency will be used to avoid interference. And of course, both
730 altimeter and TeleDongle must be configured to the same
731 frequency to successfully communicate with each other.
732 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54071664"></a>6.2. Apogee Delay</h3></div></div></div><p>
733 Apogee delay is the number of seconds after the altimeter detects flight
734 apogee that the drogue charge should be fired. In most cases, this
735 should be left at the default of 0. However, if you are flying
736 redundant electronics such as for an L3 certification, you may wish
737 to set one of your altimeters to a positive delay so that both
738 primary and backup pyrotechnic charges do not fire simultaneously.
740 The Altus Metrum apogee detection algorithm fires exactly at
741 apogee. If you are also flying an altimeter like the
742 PerfectFlite MAWD, which only supports selecting 0 or 1
743 seconds of apogee delay, you may wish to set the MAWD to 0
744 seconds delay and set the TeleMetrum to fire your backup 2
745 or 3 seconds later to avoid any chance of both charges
746 firing simultaneously. We've flown several air-frames this
747 way quite happily, including Keith's successful L3 cert.
748 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54074256"></a>6.3. Main Deployment Altitude</h3></div></div></div><p>
749 By default, the altimeter will fire the main deployment charge at an
750 elevation of 250 meters (about 820 feet) above ground. We think this
751 is a good elevation for most air-frames, but feel free to change this
752 to suit. In particular, if you are flying two altimeters, you may
754 deployment elevation for the backup altimeter to be something lower
755 than the primary so that both pyrotechnic charges don't fire
757 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54075952"></a>6.4. Maximum Flight Log</h3></div></div></div><p>
758 Changing this value will set the maximum amount of flight
759 log storage that an individual flight will use. The
760 available storage is divided into as many flights of the
761 specified size as can fit in the available space. You can
762 download and erase individual flight logs. If you fill up
763 the available storage, future flights will not get logged
764 until you erase some of the stored ones.
766 Even though our flight computers (except TeleMini v1.0) can store
767 multiple flights, we strongly recommend downloading and saving
768 flight data after each flight.
769 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54078096"></a>6.5. Ignite Mode</h3></div></div></div><p>
770 Instead of firing one charge at apogee and another charge at
771 a fixed height above the ground, you can configure the
772 altimeter to fire both at apogee or both during
773 descent. This was added to support an airframe Bdale designed that
774 had two altimeters, one in the fin can and one in the nose.
776 Providing the ability to use both igniters for apogee or
777 main allows some level of redundancy without needing two
778 flight computers. In Redundant Apogee or Redundant Main
779 mode, the two charges will be fired two seconds apart.
780 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54080208"></a>6.6. Pad Orientation</h3></div></div></div><p>
781 TeleMetrum and TeleMega measure acceleration along the axis
782 of the board. Which way the board is oriented affects the
783 sign of the acceleration value. Instead of trying to guess
784 which way the board is mounted in the air frame, the
785 altimeter must be explicitly configured for either Antenna
786 Up or Antenna Down. The default, Antenna Up, expects the end
787 of the board connected to the 70cm antenna to be nearest the
788 nose of the rocket, with the end containing the screw
789 terminals nearest the tail.
790 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54081904"></a>6.7. Configurable Pyro Channels</h3></div></div></div><p>
791 In addition to the usual Apogee and Main pyro channels,
792 TeleMega has four additional channels that can be configured
793 to activate when various flight conditions are
794 satisfied. You can select as many conditions as necessary;
795 all of them must be met in order to activate the
796 channel. The conditions available are:
797 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
798 Acceleration away from the ground. Select a value, and
799 then choose whether acceleration should be above or
800 below that value. Acceleration is positive upwards, so
801 accelerating towards the ground would produce negative
802 numbers. Acceleration during descent is noisy and
803 inaccurate, so be careful when using it during these
804 phases of the flight.
805 </p></li><li class="listitem"><p>
806 Vertical speed. Select a value, and then choose whether
807 vertical speed should be above or below that
808 value. Speed is positive upwards, so moving towards the
809 ground would produce negative numbers. Speed during
810 descent is a bit noisy and so be careful when using it
811 during these phases of the flight.
812 </p></li><li class="listitem"><p>
813 Height. Select a value, and then choose whether the
814 height above the launch pad should be above or below
816 </p></li><li class="listitem"><p>
817 Orientation. TeleMega contains a 3-axis gyroscope and
818 accelerometer which is used to measure the current
819 angle. Note that this angle is not the change in angle
820 from the launch pad, but rather absolute relative to
821 gravity; the 3-axis accelerometer is used to compute the
822 angle of the rocket on the launch pad and initialize the
823 system. Because this value is computed by integrating
824 rate gyros, it gets progressively less accurate as the
825 flight goes on. It should have an accumulated error of
826 less than 0.2°/second (after 10 seconds of flight, the
827 error should be less than 2°).
829 The usual use of the orientation configuration is to
830 ensure that the rocket is traveling mostly upwards when
831 deciding whether to ignite air starts or additional
832 stages. For that, choose a reasonable maximum angle
833 (like 20°) and set the motor igniter to require an angle
834 of less than that value.
835 </p></li><li class="listitem"><p>
836 Flight Time. Time since boost was detected. Select a
837 value and choose whether to activate the pyro channel
838 before or after that amount of time.
839 </p></li><li class="listitem"><p>
840 Ascending. A simple test saying whether the rocket is
841 going up or not. This is exactly equivalent to testing
842 whether the speed is > 0.
843 </p></li><li class="listitem"><p>
844 Descending. A simple test saying whether the rocket is
845 going down or not. This is exactly equivalent to testing
846 whether the speed is < 0.
847 </p></li><li class="listitem"><p>
848 After Motor. The flight software counts each time the
849 rocket starts accelerating (presumably due to a motor or
850 motors igniting). Use this value to count ignitions for
851 multi-staged or multi-airstart launches.
852 </p></li><li class="listitem"><p>
853 Delay. This value doesn't perform any checks, instead it
854 inserts a delay between the time when the other
855 parameters become true and when the pyro channel is
857 </p></li><li class="listitem"><p>
858 Flight State. The flight software tracks the flight
859 through a sequence of states:
860 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
861 Boost. The motor has lit and the rocket is
862 accelerating upwards.
863 </p></li><li class="listitem"><p>
864 Fast. The motor has burned out and the rocket is
865 descellerating, but it is going faster than 200m/s.
866 </p></li><li class="listitem"><p>
867 Coast. The rocket is still moving upwards and
868 decelerating, but the speed is less than 200m/s.
869 </p></li><li class="listitem"><p>
870 Drogue. The rocket has reached apogee and is heading
871 back down, but is above the configured Main
873 </p></li><li class="listitem"><p>
874 Main. The rocket is still descending, and is below
876 </p></li><li class="listitem"><p>
877 Landed. The rocket is no longer moving.
878 </p></li></ol></div><p>
880 You can select a state to limit when the pyro channel
881 may activate; note that the check is based on when the
882 rocket transitions <span class="emphasis"><em>into</em></span> the state, and so checking for
883 “greater than Boost” means that the rocket is currently
884 in boost or some later state.
886 When a motor burns out, the rocket enters either Fast or
887 Coast state (depending on how fast it is moving). If the
888 computer detects upwards acceleration again, it will
889 move back to Boost state.
890 </p></li></ul></div></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp54104384"></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="#idp54108000">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54120720">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp54136352">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp54141808">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp54148672">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp54155520">1.5. Table</a></span></dt><dt><span class="section"><a href="#idp54159104">1.6. Site Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54164768">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp54168720">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp54170752">4. Graph Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54173136">4.1. Flight Graph</a></span></dt><dt><span class="section"><a href="#idp54177584">4.2. Configure Graph</a></span></dt><dt><span class="section"><a href="#idp54181248">4.3. Flight Statistics</a></span></dt><dt><span class="section"><a href="#idp54184768">4.4. Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54188624">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54190192">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp54192544">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54194032">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54206336">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp54208304">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp54209920">6.3. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp54211424">6.4. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp54213072">6.5. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp54214368">6.6. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp54215872">6.7. Callsign</a></span></dt><dt><span class="section"><a href="#idp54217184">6.8. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp54218624">6.9. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp54225616">6.10. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp54230832">6.11. Configure Pyro Channels</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54236640">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54240144">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp54245168">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp54247168">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp54249408">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp54250912">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp54252192">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp54253696">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54255328">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54266448">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp54268016">8.2. Radio Calibration</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54269648">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp54271280">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp54276912">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp54280768">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp54286464">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>
891 The AltosUI program provides a graphical user interface for
892 interacting with the Altus Metrum product family. AltosUI can
893 monitor telemetry data, configure devices and many other
894 tasks. The primary interface window provides a selection of
895 buttons, one for each major activity in the system. This chapter
896 is split into sections, each of which documents one of the tasks
897 provided from the top-level toolbar.
898 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54108000"></a>1. Monitor Flight</h2></div><div><h3 class="subtitle">Receive, Record and Display Telemetry Data</h3></div></div></div><p>
899 Selecting this item brings up a dialog box listing all of the
900 connected TeleDongle devices. When you choose one of these,
901 AltosUI will create a window to display telemetry data as
902 received by the selected TeleDongle device.
903 </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>
904 All telemetry data received are automatically recorded in
905 suitable log files. The name of the files includes the current
906 date and rocket serial and flight numbers.
908 The radio frequency being monitored by the TeleDongle device is
909 displayed at the top of the window. You can configure the
910 frequency by clicking on the frequency box and selecting the desired
911 frequency. AltosUI remembers the last frequency selected for each
912 TeleDongle and selects that automatically the next time you use
915 Below the TeleDongle frequency selector, the window contains a few
916 significant pieces of information about the altimeter providing
917 the telemetry data stream:
918 </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
920 </p></li><li class="listitem"><p>
921 The rocket flight state. Each flight passes through several
922 states including Pad, Boost, Fast, Coast, Drogue, Main and
924 </p></li><li class="listitem"><p>
925 The Received Signal Strength Indicator value. This lets
926 you know how strong a signal TeleDongle is receiving. The
927 radio inside TeleDongle operates down to about -99dBm;
928 weaker signals may not be receivable. The packet link uses
929 error detection and correction techniques which prevent
930 incorrect data from being reported.
931 </p></li><li class="listitem"><p>
932 The age of the displayed data, in seconds since the last
933 successfully received telemetry packet. In normal operation
934 this will stay in the low single digits. If the number starts
935 counting up, then you are no longer receiving data over the radio
936 link from the flight computer.
937 </p></li></ul></div><p>
938 Finally, the largest portion of the window contains a set of
939 tabs, each of which contain some information about the rocket.
940 They're arranged in 'flight order' so that as the flight
941 progresses, the selected tab automatically switches to display
942 data relevant to the current state of the flight. You can select
943 other tabs at any time. The final 'table' tab displays all of
944 the raw telemetry values in one place in a spreadsheet-like format.
945 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54120720"></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>
946 The 'Launch Pad' tab shows information used to decide when the
947 rocket is ready for flight. The first elements include red/green
948 indicators, if any of these is red, you'll want to evaluate
949 whether the rocket is ready to launch:
950 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Battery Voltage</span></dt><dd><p>
951 This indicates whether the Li-Po battery powering the
952 flight computer has sufficient charge to last for
953 the duration of the flight. A value of more than
954 3.8V is required for a 'GO' status.
955 </p></dd><dt><span class="term">Apogee Igniter Voltage</span></dt><dd><p>
956 This indicates whether the apogee
957 igniter has continuity. If the igniter has a low
958 resistance, then the voltage measured here will be close
959 to the Li-Po battery voltage. A value greater than 3.2V is
960 required for a 'GO' status.
961 </p></dd><dt><span class="term">Main Igniter Voltage</span></dt><dd><p>
962 This indicates whether the main
963 igniter has continuity. If the igniter has a low
964 resistance, then the voltage measured here will be close
965 to the Li-Po battery voltage. A value greater than 3.2V is
966 required for a 'GO' status.
967 </p></dd><dt><span class="term">On-board Data Logging</span></dt><dd><p>
968 This indicates whether there is
969 space remaining on-board to store flight data for the
970 upcoming flight. If you've downloaded data, but failed
971 to erase flights, there may not be any space
972 left. Most of our flight computers can store multiple
973 flights, depending on the configured maximum flight log
974 size. TeleMini v1.0 stores only a single flight, so it
976 downloaded and erased after each flight to capture
977 data. This only affects on-board flight logging; the
978 altimeter will still transmit telemetry and fire
979 ejection charges at the proper times even if the flight
980 data storage is full.
981 </p></dd><dt><span class="term">GPS Locked</span></dt><dd><p>
982 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
983 currently able to compute position information. GPS requires
984 at least 4 satellites to compute an accurate position.
985 </p></dd><dt><span class="term">GPS Ready</span></dt><dd><p>
986 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
987 10 consecutive positions without losing lock. This ensures
988 that the GPS receiver has reliable reception from the
990 </p></dd></dl></div><p>
992 The Launchpad tab also shows the computed launch pad position
993 and altitude, averaging many reported positions to improve the
995 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54136352"></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>
996 This tab is shown during Boost, Fast and Coast
997 phases. The information displayed here helps monitor the
998 rocket as it heads towards apogee.
1000 The height, speed, acceleration and tilt are shown along
1001 with the maximum values for each of them. This allows you to
1002 quickly answer the most commonly asked questions you'll hear
1005 The current latitude and longitude reported by the GPS are
1006 also shown. Note that under high acceleration, these values
1007 may not get updated as the GPS receiver loses position
1008 fix. Once the rocket starts coasting, the receiver should
1009 start reporting position again.
1011 Finally, the current igniter voltages are reported as in the
1012 Launch Pad tab. This can help diagnose deployment failures
1013 caused by wiring which comes loose under high acceleration.
1014 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54141808"></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>
1015 Once the rocket has reached apogee and (we hope) activated the
1016 apogee charge, attention switches to tracking the rocket on
1017 the way back to the ground, and for dual-deploy flights,
1018 waiting for the main charge to fire.
1020 To monitor whether the apogee charge operated correctly, the
1021 current descent rate is reported along with the current
1022 height. Good descent rates vary based on the choice of recovery
1023 components, but generally range from 15-30m/s on drogue and should
1024 be below 10m/s when under the main parachute in a dual-deploy flight.
1026 With GPS-equipped flight computers, you can locate the rocket in the
1027 sky using the elevation and bearing information to figure
1028 out where to look. Elevation is in degrees above the
1029 horizon. Bearing is reported in degrees relative to true
1030 north. Range can help figure out how big the rocket will
1031 appear. Ground Distance shows how far it is to a point
1032 directly under the rocket and can help figure out where the
1033 rocket is likely to land. Note that all of these values are
1034 relative to the pad location. If the elevation is near 90°,
1035 the rocket is over the pad, not over you.
1037 Finally, the igniter voltages are reported in this tab as
1038 well, both to monitor the main charge as well as to see what
1039 the status of the apogee charge is. Note that some commercial
1040 e-matches are designed to retain continuity even after being
1041 fired, and will continue to show as green or return from red to
1043 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54148672"></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>
1044 Once the rocket is on the ground, attention switches to
1045 recovery. While the radio signal is often lost once the
1046 rocket is on the ground, the last reported GPS position is
1047 generally within a short distance of the actual landing location.
1049 The last reported GPS position is reported both by
1050 latitude and longitude as well as a bearing and distance from
1051 the launch pad. The distance should give you a good idea of
1052 whether to walk or hitch a ride. Take the reported
1053 latitude and longitude and enter them into your hand-held GPS
1054 unit and have that compute a track to the landing location.
1056 Our flight computers will continue to transmit RDF
1057 tones after landing, allowing you to locate the rocket by
1058 following the radio signal if necessary. You may need to get
1059 away from the clutter of the flight line, or even get up on
1060 a hill (or your neighbor's RV roof) to receive the RDF signal.
1062 The maximum height, speed and acceleration reported
1063 during the flight are displayed for your admiring observers.
1064 The accuracy of these immediate values depends on the quality
1065 of your radio link and how many packets were received.
1066 Recovering the on-board data after flight may yield
1067 more precise results.
1069 To get more detailed information about the flight, you can
1070 click on the 'Graph Flight' button which will bring up a
1071 graph window for the current flight.
1072 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54155520"></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>
1073 The table view shows all of the data available from the
1074 flight computer. Probably the most useful data on
1075 this tab is the detailed GPS information, which includes
1076 horizontal dilution of precision information, and
1077 information about the signal being received from the satellites.
1078 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54159104"></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>
1079 When the TeleMetrum has a GPS fix, the Site Map tab will map
1080 the rocket's position to make it easier for you to locate the
1081 rocket, both while it is in the air, and when it has landed. The
1082 rocket's state is indicated by color: white for pad, red for
1083 boost, pink for fast, yellow for coast, light blue for drogue,
1084 dark blue for main, and black for landed.
1086 The map's scale is approximately 3m (10ft) per pixel. The map
1087 can be dragged using the left mouse button. The map will attempt
1088 to keep the rocket roughly centered while data is being received.
1090 Images are fetched automatically via the Google Maps Static API,
1091 and cached on disk for reuse. If map images cannot be downloaded,
1092 the rocket's path will be traced on a dark gray background
1095 You can pre-load images for your favorite launch sites
1096 before you leave home; check out the 'Preload Maps' section below.
1097 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54164768"></a>2. Save Flight Data</h2></div></div></div><p>
1098 The altimeter records flight data to its internal flash memory.
1099 TeleMetrum data is recorded at a much higher rate than the telemetry
1100 system can handle, and is not subject to radio drop-outs. As
1101 such, it provides a more complete and precise record of the
1102 flight. The 'Save Flight Data' button allows you to read the
1103 flash memory and write it to disk.
1105 Clicking on the 'Save Flight Data' button brings up a list of
1106 connected flight computers and TeleDongle devices. If you select a
1107 flight computer, the flight data will be downloaded from that
1108 device directly. If you select a TeleDongle device, flight data
1109 will be downloaded from a flight computer over radio link via the
1110 specified TeleDongle. See the chapter on Controlling An Altimeter
1111 Over The Radio Link for more information.
1113 After the device has been selected, a dialog showing the
1114 flight data saved in the device will be shown allowing you to
1115 select which flights to download and which to delete. With
1116 version 0.9 or newer firmware, you must erase flights in order
1117 for the space they consume to be reused by another
1118 flight. This prevents accidentally losing flight data
1119 if you neglect to download data before flying again. Note that
1120 if there is no more space available in the device, then no
1121 data will be recorded during the next flight.
1123 The file name for each flight log is computed automatically
1124 from the recorded flight date, altimeter serial number and
1125 flight number information.
1126 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54168720"></a>3. Replay Flight</h2></div></div></div><p>
1127 Select this button and you are prompted to select a flight
1128 record file, either a .telem file recording telemetry data or a
1129 .eeprom file containing flight data saved from the altimeter
1132 Once a flight record is selected, the flight monitor interface
1133 is displayed and the flight is re-enacted in real time. Check
1134 the Monitor Flight chapter above to learn how this window operates.
1135 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54170752"></a>4. Graph Data</h2></div></div></div><p>
1136 Select this button and you are prompted to select a flight
1137 record file, either a .telem file recording telemetry data or a
1138 .eeprom file containing flight data saved from
1141 Note that telemetry files will generally produce poor graphs
1142 due to the lower sampling rate and missed telemetry packets.
1143 Use saved flight data in .eeprom files for graphing where possible.
1145 Once a flight record is selected, a window with multiple tabs is
1147 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54173136"></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>
1148 By default, the graph contains acceleration (blue),
1149 velocity (green) and altitude (red).
1151 The graph can be zoomed into a particular area by clicking and
1152 dragging down and to the right. Once zoomed, the graph can be
1153 reset by clicking and dragging up and to the left. Holding down
1154 control and clicking and dragging allows the graph to be panned.
1155 The right mouse button causes a pop-up menu to be displayed, giving
1156 you the option save or print the plot.
1157 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54177584"></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>
1158 This selects which graph elements to show, and, at the
1159 very bottom, lets you switch between metric and
1161 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54181248"></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>
1162 Shows overall data computed from the flight.
1163 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54184768"></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>
1164 Shows a satellite image of the flight area overlaid
1165 with the path of the flight. The red concentric
1166 circles mark the launch pad, the black concentric
1167 circles mark the landing location.
1168 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54188624"></a>5. Export Data</h2></div></div></div><p>
1169 This tool takes the raw data files and makes them available for
1170 external analysis. When you select this button, you are prompted to
1171 select a flight data file, which can be either a .eeprom or .telem.
1172 The .eeprom files contain higher resolution and more continuous data,
1173 while .telem files contain receiver signal strength information.
1174 Next, a second dialog appears which is used to select
1175 where to write the resulting file. It has a selector to choose
1176 between CSV and KML file formats.
1177 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54190192"></a>5.1. Comma Separated Value Format</h3></div></div></div><p>
1178 This is a text file containing the data in a form suitable for
1179 import into a spreadsheet or other external data analysis
1180 tool. The first few lines of the file contain the version and
1181 configuration information from the altimeter, then
1182 there is a single header line which labels all of the
1183 fields. All of these lines start with a '#' character which
1184 many tools can be configured to skip over.
1186 The remaining lines of the file contain the data, with each
1187 field separated by a comma and at least one space. All of
1188 the sensor values are converted to standard units, with the
1189 barometric data reported in both pressure, altitude and
1190 height above pad units.
1191 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54192544"></a>5.2. Keyhole Markup Language (for Google Earth)</h3></div></div></div><p>
1192 This is the format used by Google Earth to provide an overlay
1193 within that application. With this, you can use Google Earth to
1194 see the whole flight path in 3D.
1195 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54194032"></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>
1196 Select this button and then select either an altimeter or
1197 TeleDongle Device from the list provided. Selecting a TeleDongle
1198 device will use the radio link to configure a remote altimeter.
1200 The first few lines of the dialog provide information about the
1201 connected device, including the product name,
1202 software version and hardware serial number. Below that are the
1203 individual configuration entries.
1205 At the bottom of the dialog, there are four buttons:
1206 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Save</span></dt><dd><p>
1207 This writes any changes to the
1208 configuration parameter block in flash memory. If you don't
1209 press this button, any changes you make will be lost.
1210 </p></dd><dt><span class="term">Reset</span></dt><dd><p>
1211 This resets the dialog to the most recently saved values,
1212 erasing any changes you have made.
1213 </p></dd><dt><span class="term">Reboot</span></dt><dd><p>
1214 This reboots the device. Use this to
1215 switch from idle to pad mode by rebooting once the rocket is
1216 oriented for flight, or to confirm changes you think you saved
1218 </p></dd><dt><span class="term">Close</span></dt><dd><p>
1219 This closes the dialog. Any unsaved changes will be
1221 </p></dd></dl></div><p>
1222 The rest of the dialog contains the parameters to be configured.
1223 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54206336"></a>6.1. Main Deploy Altitude</h3></div></div></div><p>
1224 This sets the altitude (above the recorded pad altitude) at
1225 which the 'main' igniter will fire. The drop-down menu shows
1226 some common values, but you can edit the text directly and
1227 choose whatever you like. If the apogee charge fires below
1228 this altitude, then the main charge will fire two seconds
1229 after the apogee charge fires.
1230 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54208304"></a>6.2. Apogee Delay</h3></div></div></div><p>
1231 When flying redundant electronics, it's often important to
1232 ensure that multiple apogee charges don't fire at precisely
1233 the same time, as that can over pressurize the apogee deployment
1234 bay and cause a structural failure of the air-frame. The Apogee
1235 Delay parameter tells the flight computer to fire the apogee
1236 charge a certain number of seconds after apogee has been
1238 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54209920"></a>6.3. Radio Frequency</h3></div></div></div><p>
1239 This configures which of the frequencies to use for both
1240 telemetry and packet command mode. Note that if you set this
1241 value via packet command mode, the TeleDongle frequency will
1242 also be automatically reconfigured to match so that
1243 communication will continue afterwards.
1244 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54211424"></a>6.4. RF Calibration</h3></div></div></div><p>
1245 The radios in every Altus Metrum device are calibrated at the
1246 factory to ensure that they transmit and receive on the
1247 specified frequency. If you need to you can adjust the calibration
1248 by changing this value. Do not do this without understanding what
1249 the value means, read the appendix on calibration and/or the source
1250 code for more information. To change a TeleDongle's calibration,
1251 you must reprogram the unit completely.
1252 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54213072"></a>6.5. Telemetry/RDF/APRS Enable</h3></div></div></div><p>
1253 Enables the radio for transmission during flight. When
1254 disabled, the radio will not transmit anything during flight
1256 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54214368"></a>6.6. APRS Interval</h3></div></div></div><p>
1257 How often to transmit GPS information via APRS. This option
1258 is available on TeleMetrum v2 and TeleMega
1259 boards. TeleMetrum v1 boards cannot transmit APRS
1260 packets. Note that a single APRS packet takes nearly a full
1261 second to transmit, so enabling this option will prevent
1262 sending any other telemetry during that time.
1263 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54215872"></a>6.7. Callsign</h3></div></div></div><p>
1264 This sets the call sign included in each telemetry packet. Set this
1265 as needed to conform to your local radio regulations.
1266 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54217184"></a>6.8. Maximum Flight Log Size</h3></div></div></div><p>
1267 This sets the space (in kilobytes) allocated for each flight
1268 log. The available space will be divided into chunks of this
1269 size. A smaller value will allow more flights to be stored,
1270 a larger value will record data from longer flights.
1271 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54218624"></a>6.9. Ignite Mode</h3></div></div></div><p>
1272 TeleMetrum and TeleMini provide two igniter channels as they
1273 were originally designed as dual-deploy flight
1274 computers. This configuration parameter allows the two
1275 channels to be used in different configurations.
1276 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Dual Deploy</span></dt><dd><p>
1277 This is the usual mode of operation; the
1278 'apogee' channel is fired at apogee and the 'main'
1279 channel at the height above ground specified by the
1280 'Main Deploy Altitude' during descent.
1281 </p></dd><dt><span class="term">Redundant Apogee</span></dt><dd><p>
1282 This fires both channels at
1283 apogee, the 'apogee' channel first followed after a two second
1284 delay by the 'main' channel.
1285 </p></dd><dt><span class="term">Redundant Main</span></dt><dd><p>
1286 This fires both channels at the
1287 height above ground specified by the Main Deploy
1288 Altitude setting during descent. The 'apogee'
1289 channel is fired first, followed after a two second
1290 delay by the 'main' channel.
1291 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54225616"></a>6.10. Pad Orientation</h3></div></div></div><p>
1292 Because they include accelerometers, TeleMetrum and
1293 TeleMega are sensitive to the orientation of the board. By
1294 default, they expect the antenna end to point forward. This
1295 parameter allows that default to be changed, permitting the
1296 board to be mounted with the antenna pointing aft instead.
1297 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Antenna Up</span></dt><dd><p>
1298 In this mode, the antenna end of the
1299 flight computer must point forward, in line with the
1300 expected flight path.
1301 </p></dd><dt><span class="term">Antenna Down</span></dt><dd><p>
1302 In this mode, the antenna end of the
1303 flight computer must point aft, in line with the
1304 expected flight path.
1305 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54230832"></a>6.11. 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>
1306 This opens a separate window to configure the additional
1307 pyro channels available on TeleMega. One column is
1308 presented for each channel. Each row represents a single
1309 parameter, if enabled the parameter must meet the specified
1310 test for the pyro channel to be fired. See the Pyro Channels
1311 section in the System Operation chapter above for a
1312 description of these parameters.
1314 Select conditions and set the related value; the pyro
1315 channel will be activated when <span class="emphasis"><em>all</em></span> of the
1316 conditions are met. Each pyro channel has a separate set of
1317 configuration values, so you can use different values for
1318 the same condition with different channels.
1320 Once you have selected the appropriate configuration for all
1321 of the necessary pyro channels, you can save the pyro
1322 configuration along with the rest of the flight computer
1323 configuration by pressing the 'Save' button in the main
1324 Configure Flight Computer window.
1325 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54236640"></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>
1326 This button presents a dialog so that you can configure the AltosUI global settings.
1327 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54240144"></a>7.1. Voice Settings</h3></div></div></div><p>
1328 AltosUI provides voice announcements during flight so that you
1329 can keep your eyes on the sky and still get information about
1330 the current flight status. However, sometimes you don't want
1332 </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>
1333 Plays a short message allowing you to verify
1334 that the audio system is working and the volume settings
1336 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54245168"></a>7.2. Log Directory</h3></div></div></div><p>
1337 AltosUI logs all telemetry data and saves all TeleMetrum flash
1338 data to this directory. This directory is also used as the
1339 staring point when selecting data files for display or export.
1341 Click on the directory name to bring up a directory choosing
1342 dialog, select a new directory and click 'Select Directory' to
1343 change where AltosUI reads and writes data files.
1344 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54247168"></a>7.3. Callsign</h3></div></div></div><p>
1345 This value is transmitted in each command packet sent from
1346 TeleDongle and received from an altimeter. It is not used in
1347 telemetry mode, as the callsign configured in the altimeter board
1348 is included in all telemetry packets. Configure this
1349 with the AltosUI operators call sign as needed to comply with
1350 your local radio regulations.
1352 Note that to successfully command a flight computer over the radio
1353 (to configure the altimeter, monitor idle, or fire pyro charges),
1354 the callsign configured here must exactly match the callsign
1355 configured in the flight computer. This matching is case
1357 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54249408"></a>7.4. Imperial Units</h3></div></div></div><p>
1358 This switches between metric units (meters) and imperial
1359 units (feet and miles). This affects the display of values
1360 use during flight monitoring, configuration, data graphing
1361 and all of the voice announcements. It does not change the
1362 units used when exporting to CSV files, those are always
1363 produced in metric units.
1364 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54250912"></a>7.5. Font Size</h3></div></div></div><p>
1365 Selects the set of fonts used in the flight monitor
1366 window. Choose between the small, medium and large sets.
1367 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54252192"></a>7.6. Serial Debug</h3></div></div></div><p>
1368 This causes all communication with a connected device to be
1369 dumped to the console from which AltosUI was started. If
1370 you've started it from an icon or menu entry, the output
1371 will simply be discarded. This mode can be useful to debug
1372 various serial communication issues.
1373 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54253696"></a>7.7. Manage Frequencies</h3></div></div></div><p>
1374 This brings up a dialog where you can configure the set of
1375 frequencies shown in the various frequency menus. You can
1376 add as many as you like, or even reconfigure the default
1377 set. Changing this list does not affect the frequency
1378 settings of any devices, it only changes the set of
1379 frequencies shown in the menus.
1380 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54255328"></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>
1381 Select this button and then select a TeleDongle Device from the list provided.
1383 The first few lines of the dialog provide information about the
1384 connected device, including the product name,
1385 software version and hardware serial number. Below that are the
1386 individual configuration entries.
1388 Note that the TeleDongle itself doesn't save any configuration
1389 data, the settings here are recorded on the local machine in
1390 the Java preferences database. Moving the TeleDongle to
1391 another machine, or using a different user account on the same
1392 machine will cause settings made here to have no effect.
1394 At the bottom of the dialog, there are three buttons:
1395 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Save</span></dt><dd><p>
1396 This writes any changes to the
1397 local Java preferences file. If you don't
1398 press this button, any changes you make will be lost.
1399 </p></dd><dt><span class="term">Reset</span></dt><dd><p>
1400 This resets the dialog to the most recently saved values,
1401 erasing any changes you have made.
1402 </p></dd><dt><span class="term">Close</span></dt><dd><p>
1403 This closes the dialog. Any unsaved changes will be
1405 </p></dd></dl></div><p>
1406 The rest of the dialog contains the parameters to be configured.
1407 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54266448"></a>8.1. Frequency</h3></div></div></div><p>
1408 This configures the frequency to use for both telemetry and
1409 packet command mode. Set this before starting any operation
1410 involving packet command mode so that it will use the right
1411 frequency. Telemetry monitoring mode also provides a menu to
1412 change the frequency, and that menu also sets the same Java
1413 preference value used here.
1414 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54268016"></a>8.2. Radio Calibration</h3></div></div></div><p>
1415 The radios in every Altus Metrum device are calibrated at the
1416 factory to ensure that they transmit and receive on the
1417 specified frequency. To change a TeleDongle's calibration,
1418 you must reprogram the unit completely, so this entry simply
1419 shows the current value and doesn't allow any changes.
1420 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54269648"></a>9. Flash Image</h2></div></div></div><p>
1421 This reprograms Altus Metrum devices with new
1422 firmware. TeleMetrum v1.x, TeleDongle, TeleMini and TeleBT are
1423 all reprogrammed by using another similar unit as a
1424 programming dongle (pair programming). TeleMega, TeleMetrum v2
1425 and EasyMini are all programmed directly over their USB ports
1426 (self programming). Please read the directions for flashing
1427 devices in the Updating Device Firmware chapter below.
1428 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54271280"></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>
1429 This activates the igniter circuits in the flight computer to help
1430 test recovery systems deployment. Because this command can operate
1431 over the Packet Command Link, you can prepare the rocket as
1432 for flight and then test the recovery system without needing
1433 to snake wires inside the air-frame.
1435 Selecting the 'Fire Igniter' button brings up the usual device
1436 selection dialog. Pick the desired device. This brings up another
1437 window which shows the current continuity test status for all
1438 of the pyro channels.
1440 Next, select the desired igniter to fire. This will enable the
1443 Select the 'Arm' button. This enables the 'Fire' button. The
1444 word 'Arm' is replaced by a countdown timer indicating that
1445 you have 10 seconds to press the 'Fire' button or the system
1446 will deactivate, at which point you start over again at
1447 selecting the desired igniter.
1448 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54276912"></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>
1449 This listens for telemetry packets on all of the configured
1450 frequencies, displaying information about each device it
1451 receives a packet from. You can select which of the three
1452 telemetry formats should be tried; by default, it only listens
1453 for the standard telemetry packets used in v1.0 and later
1455 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54280768"></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>
1456 Before heading out to a new launch site, you can use this to
1457 load satellite images in case you don't have internet
1458 connectivity at the site. This loads a fairly large area
1459 around the launch site, which should cover any flight you're likely to make.
1461 There's a drop-down menu of launch sites we know about; if
1462 your favorites aren't there, please let us know the lat/lon
1463 and name of the site. The contents of this list are actually
1464 downloaded from our server at run-time, so as new sites are sent
1465 in, they'll get automatically added to this list.
1467 If the launch site isn't in the list, you can manually enter the lat/lon values
1469 Clicking the 'Load Map' button will fetch images from Google
1470 Maps; note that Google limits how many images you can fetch at
1471 once, so if you load more than one launch site, you may get
1472 some gray areas in the map which indicate that Google is tired
1473 of sending data to you. Try again later.
1474 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54286464"></a>13. Monitor Idle</h2></div></div></div><p>
1475 This brings up a dialog similar to the Monitor Flight UI,
1476 except it works with the altimeter in “idle” mode by sending
1477 query commands to discover the current state rather than
1478 listening for telemetry packets. Because this uses command
1479 mode, it needs to have the TeleDongle and flight computer
1480 callsigns match exactly. If you can receive telemetry, but
1481 cannot manage to run Monitor Idle, then it's very likely that
1482 your callsigns are different in some way.
1483 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp54288560"></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="#idp54290944">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp54292880">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp54294880">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp54296336">4. AltosDroid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp54297648">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54311200">5. Downloading Flight Logs</a></span></dt></dl></div><p>
1484 AltosDroid provides the same flight monitoring capabilities as
1485 AltosUI, but runs on Android devices and is designed to connect
1486 to a TeleBT receiver over Bluetooth™. AltosDroid monitors
1487 telemetry data, logging it to internal storage in the Android
1488 device, and presents that data in a UI the same way the 'Monitor
1489 Flight' window does in AltosUI.
1491 This manual will explain how to configure AltosDroid, connect
1492 to TeleBT, operate the flight monitoring interface and describe
1493 what the displayed data means.
1494 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54290944"></a>1. Installing AltosDroid</h2></div></div></div><p>
1495 AltosDroid is available from the Google Play store. To install
1496 it on your Android device, open the Google Play Store
1497 application and search for “altosdroid”. Make sure you don't
1498 have a space between “altos” and “droid” or you probably won't
1499 find what you want. That should bring you to the right page
1500 from which you can download and install the application.
1501 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54292880"></a>2. Connecting to TeleBT</h2></div></div></div><p>
1502 Press the Android 'Menu' button or soft-key to see the
1503 configuration options available. Select the 'Connect a device'
1504 option and then the 'Scan for devices' entry at the bottom to
1505 look for your TeleBT device. Select your device, and when it
1506 asks for the code, enter '1234'.
1508 Subsequent connections will not require you to enter that
1509 code, and your 'paired' device will appear in the list without
1511 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54294880"></a>3. Configuring AltosDroid</h2></div></div></div><p>
1512 The only configuration option available for AltosDroid is
1513 which frequency to listen on. Press the Android 'Menu' button
1514 or soft-key and pick the 'Select radio frequency' entry. That
1515 brings up a menu of pre-set radio frequencies; pick the one
1516 which matches your altimeter.
1517 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54296336"></a>4. AltosDroid Flight Monitoring</h2></div></div></div><p>
1518 AltosDroid is designed to mimic the AltosUI flight monitoring
1519 display, providing separate tabs for each stage of your rocket
1520 flight along with a tab containing a map of the local area
1521 with icons marking the current location of the altimeter and
1523 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54297648"></a>4.1. Pad</h3></div></div></div><p>
1524 The 'Launch Pad' tab shows information used to decide when the
1525 rocket is ready for flight. The first elements include red/green
1526 indicators, if any of these is red, you'll want to evaluate
1527 whether the rocket is ready to launch:
1528 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Battery Voltage</span></dt><dd><p>
1529 This indicates whether the Li-Po battery
1530 powering the TeleMetrum has sufficient charge to last for
1531 the duration of the flight. A value of more than
1532 3.8V is required for a 'GO' status.
1533 </p></dd><dt><span class="term">Apogee Igniter Voltage</span></dt><dd><p>
1534 This indicates whether the apogee
1535 igniter has continuity. If the igniter has a low
1536 resistance, then the voltage measured here will be close
1537 to the Li-Po battery voltage. A value greater than 3.2V is
1538 required for a 'GO' status.
1539 </p></dd><dt><span class="term">Main Igniter Voltage</span></dt><dd><p>
1540 This indicates whether the main
1541 igniter has continuity. If the igniter has a low
1542 resistance, then the voltage measured here will be close
1543 to the Li-Po battery voltage. A value greater than 3.2V is
1544 required for a 'GO' status.
1545 </p></dd><dt><span class="term">On-board Data Logging</span></dt><dd><p>
1546 This indicates whether there is
1547 space remaining on-board to store flight data for the
1548 upcoming flight. If you've downloaded data, but failed
1549 to erase flights, there may not be any space
1550 left. TeleMetrum can store multiple flights, depending
1551 on the configured maximum flight log size. TeleMini
1552 stores only a single flight, so it will need to be
1553 downloaded and erased after each flight to capture
1554 data. This only affects on-board flight logging; the
1555 altimeter will still transmit telemetry and fire
1556 ejection charges at the proper times.
1557 </p></dd><dt><span class="term">GPS Locked</span></dt><dd><p>
1558 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
1559 currently able to compute position information. GPS requires
1560 at least 4 satellites to compute an accurate position.
1561 </p></dd><dt><span class="term">GPS Ready</span></dt><dd><p>
1562 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
1563 10 consecutive positions without losing lock. This ensures
1564 that the GPS receiver has reliable reception from the
1566 </p></dd></dl></div><p>
1568 The Launchpad tab also shows the computed launch pad position
1569 and altitude, averaging many reported positions to improve the
1570 accuracy of the fix.
1571 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54311200"></a>5. Downloading Flight Logs</h2></div></div></div><p>
1572 AltosDroid always saves every bit of telemetry data it
1573 receives. To download that to a computer for use with AltosUI,
1574 simply remove the SD card from your Android device, or connect
1575 your device to your computer's USB port and browse the files
1576 on that device. You will find '.telem' files in the TeleMetrum
1577 directory that will work with AltosUI directly.
1578 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp54312864"></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="#idp54313504">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp54315408">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp54317872">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp54331184">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp54333728">5. Future Plans</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54313504"></a>1. Being Legal</h2></div></div></div><p>
1579 First off, in the US, you need an <a class="ulink" href="http://www.altusmetrum.org/Radio/" target="_top">amateur radio license</a> or
1580 other authorization to legally operate the radio transmitters that are part
1582 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54315408"></a>2. In the Rocket</h2></div></div></div><p>
1583 In the rocket itself, you just need a flight computer and
1584 a single-cell, 3.7 volt nominal Li-Po rechargeable battery. An
1585 850mAh battery weighs less than a 9V alkaline battery, and will
1586 run a TeleMetrum or TeleMega for hours.
1587 A 110mAh battery weighs less than a triple A battery and is a good
1588 choice for use with TeleMini.
1590 By default, we ship flight computers with a simple wire antenna.
1591 If your electronics bay or the air-frame it resides within is made
1592 of carbon fiber, which is opaque to RF signals, you may prefer to
1593 install an SMA connector so that you can run a coaxial cable to an
1594 antenna mounted elsewhere in the rocket. However, note that the
1595 GPS antenna is fixed on all current products, so you really want
1596 to install the flight computer in a bay made of RF-transparent
1597 materials if at all possible.
1598 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54317872"></a>3. On the Ground</h2></div></div></div><p>
1599 To receive the data stream from the rocket, you need an antenna and short
1600 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
1601 adapter instead of feedline between the antenna feedpoint and
1602 TeleDongle, as this will give you the best performance. The
1603 TeleDongle in turn plugs directly into the USB port on a notebook
1604 computer. Because TeleDongle looks like a simple serial port, your computer
1605 does not require special device drivers... just plug it in.
1607 The GUI tool, AltosUI, is written in Java and runs across
1608 Linux, Mac OS and Windows. There's also a suite of C tools
1609 for Linux which can perform most of the same tasks.
1611 Alternatively, a TeleBT attached with an SMA to BNC adapter at the
1612 feed point of a hand-held yagi used in conjunction with an Android
1613 device running AltosDroid makes an outstanding ground station.
1615 After the flight, you can use the radio link to extract the more detailed data
1616 logged in either TeleMetrum or TeleMini devices, or you can use a mini USB cable to plug into the
1617 TeleMetrum board directly. Pulling out the data without having to open up
1618 the rocket is pretty cool! A USB cable is also how you charge the Li-Po
1619 battery, so you'll want one of those anyway... the same cable used by lots
1620 of digital cameras and other modern electronic stuff will work fine.
1622 If your rocket lands out of sight, you may enjoy having a hand-held
1623 GPS receiver, so that you can put in a way-point for the last
1624 reported rocket position before touch-down. This makes looking for
1625 your rocket a lot like Geo-Caching... just go to the way-point and
1626 look around starting from there. AltosDroid on an Android device
1627 with GPS receiver works great for this, too!
1629 You may also enjoy having a ham radio “HT” that covers the 70cm band... you
1630 can use that with your antenna to direction-find the rocket on the ground
1631 the same way you can use a Walston or Beeline tracker. This can be handy
1632 if the rocket is hiding in sage brush or a tree, or if the last GPS position
1633 doesn't get you close enough because the rocket dropped into a canyon, or
1634 the wind is blowing it across a dry lake bed, or something like that... Keith
1635 currently uses a Yaesu VX-7R, Bdale has a Baofung UV-5R
1636 which isn't as nice, but was a whole lot cheaper.
1638 So, to recap, on the ground the hardware you'll need includes:
1639 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1640 an antenna and feed-line or adapter
1641 </p></li><li class="listitem"><p>
1643 </p></li><li class="listitem"><p>
1645 </p></li><li class="listitem"><p>
1646 optionally, a hand-held GPS receiver
1647 </p></li><li class="listitem"><p>
1648 optionally, an HT or receiver covering 435 MHz
1649 </p></li></ol></div><p>
1651 The best hand-held commercial directional antennas we've found for radio
1652 direction finding rockets are from
1653 <a class="ulink" href="http://www.arrowantennas.com/" target="_top">
1656 The 440-3 and 440-5 are both good choices for finding a
1657 TeleMetrum- or TeleMini- equipped rocket when used with a suitable
1658 70cm HT. TeleDongle and an SMA to BNC adapter fit perfectly
1659 between the driven element and reflector of Arrow antennas.
1660 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54331184"></a>4. Data Analysis</h2></div></div></div><p>
1661 Our software makes it easy to log the data from each flight, both the
1662 telemetry received during the flight itself, and the more
1663 complete data log recorded in the flash memory on the altimeter
1664 board. Once this data is on your computer, our post-flight tools make it
1665 easy to quickly get to the numbers everyone wants, like apogee altitude,
1666 max acceleration, and max velocity. You can also generate and view a
1667 standard set of plots showing the altitude, acceleration, and
1668 velocity of the rocket during flight. And you can even export a TeleMetrum data file
1669 usable with Google Maps and Google Earth for visualizing the flight path
1670 in two or three dimensions!
1672 Our ultimate goal is to emit a set of files for each flight that can be
1673 published as a web page per flight, or just viewed on your local disk with
1675 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54333728"></a>5. Future Plans</h2></div></div></div><p>
1676 We've designed a simple GPS based radio tracker called TeleGPS.
1677 If all goes well, we hope to introduce this in the first
1680 We have designed and prototyped several “companion boards” that
1681 can attach to the companion connector on TeleMetrum and TeleMega
1682 flight computers to collect more data, provide more pyro channels,
1683 and so forth. We do not yet know if or when any of these boards
1684 will be produced in enough quantity to sell. If you have specific
1685 interests for data collection or control of events in your rockets
1686 beyond the capabilities of our existing productions, please let
1689 Because all of our work is open, both the hardware designs and the
1690 software, if you have some great idea for an addition to the current
1691 Altus Metrum family, feel free to dive in and help! Or let us know
1692 what you'd like to see that we aren't already working on, and maybe
1693 we'll get excited about it too...
1696 <a class="ulink" href="http://altusmetrum.org/" target="_top">web site</a> for more news
1697 and information as our family of products evolves!
1698 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp54338112"></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="#idp54339568">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp54344400">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp54349968">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp54354752">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp54362320">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp54365120">6. Ground Testing</a></span></dt></dl></div><p>
1699 Building high-power rockets that fly safely is hard enough. Mix
1700 in some sophisticated electronics and a bunch of radio energy
1701 and some creativity and/or compromise may be required. This chapter
1702 contains some suggestions about how to install Altus Metrum
1703 products into a rocket air-frame, including how to safely and
1704 reliably mix a variety of electronics into the same air-frame.
1705 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54339568"></a>1. Mounting the Altimeter</h2></div></div></div><p>
1706 The first consideration is to ensure that the altimeter is
1707 securely fastened to the air-frame. For most of our products, we
1708 prefer nylon standoffs and nylon screws; they're good to at least 50G
1709 and cannot cause any electrical issues on the board. Metal screws
1710 and standoffs are fine, too, just be careful to avoid electrical
1711 shorts! For TeleMini v1.0, we usually cut small pieces of 1/16 inch
1713 under the screw holes, and then take 2x56 nylon screws and
1714 screw them through the TeleMini mounting holes, through the
1715 balsa and into the underlying material.
1716 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1717 Make sure accelerometer-equipped products like TeleMetrum and
1718 TeleMega are aligned precisely along the axis of
1719 acceleration so that the accelerometer can accurately
1720 capture data during the flight.
1721 </p></li><li class="listitem"><p>
1722 Watch for any metal touching components on the
1723 board. Shorting out connections on the bottom of the board
1724 can cause the altimeter to fail during flight.
1725 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54344400"></a>2. Dealing with the Antenna</h2></div></div></div><p>
1726 The antenna supplied is just a piece of solid, insulated,
1727 wire. If it gets damaged or broken, it can be easily
1728 replaced. It should be kept straight and not cut; bending or
1729 cutting it will change the resonant frequency and/or
1730 impedance, making it a less efficient radiator and thus
1731 reducing the range of the telemetry signal.
1733 Keeping metal away from the antenna will provide better range
1734 and a more even radiation pattern. In most rockets, it's not
1735 entirely possible to isolate the antenna from metal
1736 components; there are often bolts, all-thread and wires from other
1737 electronics to contend with. Just be aware that the more stuff
1738 like this around the antenna, the lower the range.
1740 Make sure the antenna is not inside a tube made or covered
1741 with conducting material. Carbon fiber is the most common
1742 culprit here -- CF is a good conductor and will effectively
1743 shield the antenna, dramatically reducing signal strength and
1744 range. Metallic flake paint is another effective shielding
1745 material which should be avoided around any antennas.
1747 If the ebay is large enough, it can be convenient to simply
1748 mount the altimeter at one end and stretch the antenna out
1749 inside. Taping the antenna to the sled can keep it straight
1750 under acceleration. If there are metal rods, keep the
1751 antenna as far away as possible.
1753 For a shorter ebay, it's quite practical to have the antenna
1754 run through a bulkhead and into an adjacent bay. Drill a small
1755 hole in the bulkhead, pass the antenna wire through it and
1756 then seal it up with glue or clay. We've also used acrylic
1757 tubing to create a cavity for the antenna wire. This works a
1758 bit better in that the antenna is known to stay straight and
1759 not get folded by recovery components in the bay. Angle the
1760 tubing towards the side wall of the rocket and it ends up
1761 consuming very little space.
1763 If you need to place the UHF antenna at a distance from the
1764 altimeter, you can replace the antenna with an edge-mounted
1765 SMA connector, and then run 50Ω coax from the board to the
1766 antenna. Building a remote antenna is beyond the scope of this
1768 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54349968"></a>3. Preserving GPS Reception</h2></div></div></div><p>
1769 The GPS antenna and receiver used in TeleMetrum and TeleMega is
1770 highly sensitive and normally have no trouble tracking enough
1771 satellites to provide accurate position information for
1772 recovering the rocket. However, there are many ways the GPS signal
1773 can end up attenuated, negatively affecting GPS performance.
1774 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1775 Conductive tubing or coatings. Carbon fiber and metal
1776 tubing, or metallic paint will all dramatically attenuate the
1777 GPS signal. We've never heard of anyone successfully
1778 receiving GPS from inside these materials.
1779 </p></li><li class="listitem"><p>
1780 Metal components near the GPS patch antenna. These will
1781 de-tune the patch antenna, changing the resonant frequency
1782 away from the L1 carrier and reduce the effectiveness of the
1783 antenna. You can place as much stuff as you like beneath the
1784 antenna as that's covered with a ground plane. But, keep
1785 wires and metal out from above the patch antenna.
1786 </p></li></ol></div><p>
1787 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54354752"></a>4. Radio Frequency Interference</h2></div></div></div><p>
1788 Any altimeter will generate RFI; the digital circuits use
1789 high-frequency clocks that spray radio interference across a
1790 wide band. Altus Metrum altimeters generate intentional radio
1791 signals as well, increasing the amount of RF energy around the board.
1793 Rocketry altimeters also use precise sensors measuring air
1794 pressure and acceleration. Tiny changes in voltage can cause
1795 these sensor readings to vary by a huge amount. When the
1796 sensors start mis-reporting data, the altimeter can either
1797 fire the igniters at the wrong time, or not fire them at all.
1799 Voltages are induced when radio frequency energy is
1800 transmitted from one circuit to another. Here are things that
1801 influence the induced voltage and current:
1802 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
1803 Keep wires from different circuits apart. Moving circuits
1804 further apart will reduce RFI.
1805 </p></li><li class="listitem"><p>
1806 Avoid parallel wires from different circuits. The longer two
1807 wires run parallel to one another, the larger the amount of
1808 transferred energy. Cross wires at right angles to reduce
1810 </p></li><li class="listitem"><p>
1811 Twist wires from the same circuits. Two wires the same
1812 distance from the transmitter will get the same amount of
1813 induced energy which will then cancel out. Any time you have
1814 a wire pair running together, twist the pair together to
1815 even out distances and reduce RFI. For altimeters, this
1816 includes battery leads, switch hookups and igniter
1818 </p></li><li class="listitem"><p>
1819 Avoid resonant lengths. Know what frequencies are present
1820 in the environment and avoid having wire lengths near a
1821 natural resonant length. Altus Metrum products transmit on the
1822 70cm amateur band, so you should avoid lengths that are a
1823 simple ratio of that length; essentially any multiple of ¼
1824 of the wavelength (17.5cm).
1825 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54362320"></a>5. The Barometric Sensor</h2></div></div></div><p>
1826 Altusmetrum altimeters measure altitude with a barometric
1827 sensor, essentially measuring the amount of air above the
1828 rocket to figure out how high it is. A large number of
1829 measurements are taken as the altimeter initializes itself to
1830 figure out the pad altitude. Subsequent measurements are then
1831 used to compute the height above the pad.
1833 To accurately measure atmospheric pressure, the ebay
1834 containing the altimeter must be vented outside the
1835 air-frame. The vent must be placed in a region of linear
1836 airflow, have smooth edges, and away from areas of increasing or
1837 decreasing pressure.
1839 All barometric sensors are quite sensitive to chemical damage from
1840 the products of APCP or BP combustion, so make sure the ebay is
1841 carefully sealed from any compartment which contains ejection
1843 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54365120"></a>6. Ground Testing</h2></div></div></div><p>
1844 The most important aspect of any installation is careful
1845 ground testing. Bringing an air-frame up to the LCO table which
1846 hasn't been ground tested can lead to delays or ejection
1847 charges firing on the pad, or, even worse, a recovery system
1850 Do a 'full systems' test that includes wiring up all igniters
1851 without any BP and turning on all of the electronics in flight
1852 mode. This will catch any mistakes in wiring and any residual
1853 RFI issues that might accidentally fire igniters at the wrong
1854 time. Let the air-frame sit for several minutes, checking for
1855 adequate telemetry signal strength and GPS lock. If any igniters
1856 fire unexpectedly, find and resolve the issue before loading any
1859 Ground test the ejection charges. Prepare the rocket for
1860 flight, loading ejection charges and igniters. Completely
1861 assemble the air-frame and then use the 'Fire Igniters'
1862 interface through a TeleDongle to command each charge to
1863 fire. Make sure the charge is sufficient to robustly separate
1864 the air-frame and deploy the recovery system.
1865 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp54368288"></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="#idp54372304">1.
1866 Updating TeleMega, TeleMetrum v2 or EasyMini Firmware
1867 </a></span></dt><dd><dl><dt><span class="section"><a href="#idp54381120">1.1. Recovering From Self-Flashing Failure</a></span></dt></dl></dd><dt><span class="section"><a href="#idp54390096">2. Pair Programming</a></span></dt><dt><span class="section"><a href="#idp54391536">3. Updating TeleMetrum v1.x Firmware</a></span></dt><dt><span class="section"><a href="#idp54404576">4. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp54417968">5. Updating TeleDongle Firmware</a></span></dt></dl></div><p>
1868 TeleMega, TeleMetrum v2 and EasyMini are all programmed directly
1869 over their USB connectors (self programming). TeleMetrum v1, TeleMini and
1870 TeleDongle are all programmed by using another device as a
1871 programmer (pair programming). It's important to recognize which
1872 kind of devices you have before trying to reprogram them.
1874 You may wish to begin by ensuring you have current firmware images.
1875 These are distributed as part of the AltOS software bundle that
1876 also includes the AltosUI ground station program. Newer ground
1877 station versions typically work fine with older firmware versions,
1878 so you don't need to update your devices just to try out new
1879 software features. You can always download the most recent
1880 version from <a class="ulink" href="http://www.altusmetrum.org/AltOS/" target="_top">http://www.altusmetrum.org/AltOS/</a>.
1882 If you need to update the firmware on a TeleDongle, we recommend
1883 updating the altimeter first, before updating TeleDongle. However,
1884 note that TeleDongle rarely need to be updated. Any firmware version
1885 1.0.1 or later will work, version 1.2.1 may have improved receiver
1886 performance slightly.
1888 Self-programmable devices (TeleMega, TeleMetrum v2 and EasyMini)
1889 are reprogrammed by connecting them to your computer over USB
1890 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54372304"></a>1.
1891 Updating TeleMega, TeleMetrum v2 or EasyMini Firmware
1892 </h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1893 Attach a battery and power switch to the target
1894 device. Power up the device.
1895 </p></li><li class="listitem"><p>
1896 Using a Micro USB cable, connect the target device to your
1897 computer's USB socket.
1898 </p></li><li class="listitem"><p>
1899 Run AltosUI, and select 'Flash Image' from the File menu.
1900 </p></li><li class="listitem"><p>
1901 Select the target device in the Device Selection dialog.
1902 </p></li><li class="listitem"><p>
1903 Select the image you want to flash to the device, which
1904 should have a name in the form
1905 <product>-v<product-version>-<software-version>.ihx, such
1906 as TeleMega-v1.0-1.3.0.ihx.
1907 </p></li><li class="listitem"><p>
1908 Make sure the configuration parameters are reasonable
1909 looking. If the serial number and/or RF configuration
1910 values aren't right, you'll need to change them.
1911 </p></li><li class="listitem"><p>
1912 Hit the 'OK' button and the software should proceed to flash
1913 the device with new firmware, showing a progress bar.
1914 </p></li><li class="listitem"><p>
1915 Verify that the device is working by using the 'Configure
1916 Altimeter' item to check over the configuration.
1917 </p></li></ol></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp54381120"></a>1.1. Recovering From Self-Flashing Failure</h3></div></div></div><p>
1918 If the firmware loading fails, it can leave the device
1919 unable to boot. Not to worry, you can force the device to
1920 start the boot loader instead, which will let you try to
1921 flash the device again.
1923 On each device, connecting two pins from one of the exposed
1924 connectors will force the boot loader to start, even if the
1925 regular operating system has been corrupted in some way.
1926 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">TeleMega</span></dt><dd><p>
1927 Connect pin 6 and pin 1 of the companion connector. Pin 1
1928 can be identified by the square pad around it, and then
1929 the pins could sequentially across the board. Be very
1930 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
1931 anything as that is connected directly to the battery. Pin
1932 7 carries 3.3V and the board will crash if that is
1933 connected to pin 1, but shouldn't damage the board.
1934 </p></dd><dt><span class="term">TeleMetrum v2</span></dt><dd><p>
1935 Connect pin 6 and pin 1 of the companion connector. Pin 1
1936 can be identified by the square pad around it, and then
1937 the pins could sequentially across the board. Be very
1938 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
1939 anything as that is connected directly to the battery. Pin
1940 7 carries 3.3V and the board will crash if that is
1941 connected to pin 1, but shouldn't damage the board.
1942 </p></dd><dt><span class="term">EasyMini</span></dt><dd><p>
1943 Connect pin 6 and pin 1 of the debug connector, which is
1944 the six holes next to the beeper. Pin 1 can be identified
1945 by the square pad around it, and then the pins could
1946 sequentially across the board, making Pin 6 the one on the
1947 other end of the row.
1948 </p></dd></dl></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54390096"></a>2. Pair Programming</h2></div></div></div><p>
1949 The big concept to understand is that you have to use a
1950 TeleMega, TeleMetrum or TeleDongle as a programmer to update a
1951 pair programmed device. Due to limited memory resources in the
1952 cc1111, we don't support programming directly over USB for these
1954 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54391536"></a>3. Updating TeleMetrum v1.x Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1955 Find the 'programming cable' that you got as part of the starter
1956 kit, that has a red 8-pin MicroMaTch connector on one end and a
1957 red 4-pin MicroMaTch connector on the other end.
1958 </p></li><li class="listitem"><p>
1959 Take the 2 screws out of the TeleDongle case to get access
1960 to the circuit board.
1961 </p></li><li class="listitem"><p>
1962 Plug the 8-pin end of the programming cable to the
1963 matching connector on the TeleDongle, and the 4-pin end to the
1964 matching connector on the TeleMetrum.
1965 Note that each MicroMaTch connector has an alignment pin that
1966 goes through a hole in the PC board when you have the cable
1968 </p></li><li class="listitem"><p>
1969 Attach a battery to the TeleMetrum board.
1970 </p></li><li class="listitem"><p>
1971 Plug the TeleDongle into your computer's USB port, and power
1973 </p></li><li class="listitem"><p>
1974 Run AltosUI, and select 'Flash Image' from the File menu.
1975 </p></li><li class="listitem"><p>
1976 Pick the TeleDongle device from the list, identifying it as the
1978 </p></li><li class="listitem"><p>
1979 Select the image you want put on the TeleMetrum, which should have a
1980 name in the form telemetrum-v1.2-1.0.0.ihx. It should be visible
1981 in the default directory, if not you may have to poke around
1982 your system to find it.
1983 </p></li><li class="listitem"><p>
1984 Make sure the configuration parameters are reasonable
1985 looking. If the serial number and/or RF configuration
1986 values aren't right, you'll need to change them.
1987 </p></li><li class="listitem"><p>
1988 Hit the 'OK' button and the software should proceed to flash
1989 the TeleMetrum with new firmware, showing a progress bar.
1990 </p></li><li class="listitem"><p>
1991 Confirm that the TeleMetrum board seems to have updated OK, which you
1992 can do by plugging in to it over USB and using a terminal program
1993 to connect to the board and issue the 'v' command to check
1995 </p></li><li class="listitem"><p>
1996 If something goes wrong, give it another try.
1997 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54404576"></a>4. Updating TeleMini Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1998 You'll need a special 'programming cable' to reprogram the
1999 TeleMini. You can make your own using an 8-pin MicroMaTch
2000 connector on one end and a set of four pins on the other.
2001 </p></li><li class="listitem"><p>
2002 Take the 2 screws out of the TeleDongle case to get access
2003 to the circuit board.
2004 </p></li><li class="listitem"><p>
2005 Plug the 8-pin end of the programming cable to the matching
2006 connector on the TeleDongle, and the 4-pins into the holes
2007 in the TeleMini circuit board. Note that the MicroMaTch
2008 connector has an alignment pin that goes through a hole in
2009 the PC board when you have the cable oriented correctly, and
2010 that pin 1 on the TeleMini board is marked with a square pad
2011 while the other pins have round pads.
2012 </p></li><li class="listitem"><p>
2013 Attach a battery to the TeleMini board.
2014 </p></li><li class="listitem"><p>
2015 Plug the TeleDongle into your computer's USB port, and power
2017 </p></li><li class="listitem"><p>
2018 Run AltosUI, and select 'Flash Image' from the File menu.
2019 </p></li><li class="listitem"><p>
2020 Pick the TeleDongle device from the list, identifying it as the
2022 </p></li><li class="listitem"><p>
2023 Select the image you want put on the TeleMini, which should have a
2024 name in the form telemini-v1.0-1.0.0.ihx. It should be visible
2025 in the default directory, if not you may have to poke around
2026 your system to find it.
2027 </p></li><li class="listitem"><p>
2028 Make sure the configuration parameters are reasonable
2029 looking. If the serial number and/or RF configuration
2030 values aren't right, you'll need to change them.
2031 </p></li><li class="listitem"><p>
2032 Hit the 'OK' button and the software should proceed to flash
2033 the TeleMini with new firmware, showing a progress bar.
2034 </p></li><li class="listitem"><p>
2035 Confirm that the TeleMini board seems to have updated OK, which you
2036 can do by configuring it over the radio link through the TeleDongle, or
2037 letting it come up in “flight” mode and listening for telemetry.
2038 </p></li><li class="listitem"><p>
2039 If something goes wrong, give it another try.
2040 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54417968"></a>5. Updating TeleDongle Firmware</h2></div></div></div><p>
2041 Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
2042 firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
2043 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2044 Find the 'programming cable' that you got as part of the starter
2045 kit, that has a red 8-pin MicroMaTch connector on one end and a
2046 red 4-pin MicroMaTch connector on the other end.
2047 </p></li><li class="listitem"><p>
2048 Find the USB cable that you got as part of the starter kit, and
2049 plug the “mini” end in to the mating connector on TeleMetrum or TeleDongle.
2050 </p></li><li class="listitem"><p>
2051 Take the 2 screws out of the TeleDongle case to get access
2052 to the circuit board.
2053 </p></li><li class="listitem"><p>
2054 Plug the 8-pin end of the programming cable to the
2055 matching connector on the programmer, and the 4-pin end to the
2056 matching connector on the TeleDongle.
2057 Note that each MicroMaTch connector has an alignment pin that
2058 goes through a hole in the PC board when you have the cable
2060 </p></li><li class="listitem"><p>
2061 Attach a battery to the TeleMetrum board if you're using one.
2062 </p></li><li class="listitem"><p>
2063 Plug both the programmer and the TeleDongle into your computer's USB
2064 ports, and power up the programmer.
2065 </p></li><li class="listitem"><p>
2066 Run AltosUI, and select 'Flash Image' from the File menu.
2067 </p></li><li class="listitem"><p>
2068 Pick the programmer device from the list, identifying it as the
2070 </p></li><li class="listitem"><p>
2071 Select the image you want put on the TeleDongle, which should have a
2072 name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
2073 in the default directory, if not you may have to poke around
2074 your system to find it.
2075 </p></li><li class="listitem"><p>
2076 Make sure the configuration parameters are reasonable
2077 looking. If the serial number and/or RF configuration
2078 values aren't right, you'll need to change them. The TeleDongle
2079 serial number is on the “bottom” of the circuit board, and can
2080 usually be read through the translucent blue plastic case without
2081 needing to remove the board from the case.
2082 </p></li><li class="listitem"><p>
2083 Hit the 'OK' button and the software should proceed to flash
2084 the TeleDongle with new firmware, showing a progress bar.
2085 </p></li><li class="listitem"><p>
2086 Confirm that the TeleDongle board seems to have updated OK, which you
2087 can do by plugging in to it over USB and using a terminal program
2088 to connect to the board and issue the 'v' command to check
2089 the version, etc. Once you're happy, remove the programming cable
2090 and put the cover back on the TeleDongle.
2091 </p></li><li class="listitem"><p>
2092 If something goes wrong, give it another try.
2093 </p></li></ol></div><p>
2094 Be careful removing the programming cable from the locking 8-pin
2095 connector on TeleMetrum. You'll need a fingernail or perhaps a thin
2096 screwdriver or knife blade to gently pry the locking ears out
2097 slightly to extract the connector. We used a locking connector on
2098 TeleMetrum to help ensure that the cabling to companion boards
2099 used in a rocket don't ever come loose accidentally in flight.
2100 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp54434512"></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="#idp54435152">1.
2101 TeleMega Specifications
2102 </a></span></dt><dt><span class="section"><a href="#idp54446496">2.
2103 TeleMetrum v2 Specifications
2104 </a></span></dt><dt><span class="section"><a href="#idp54457056">3. TeleMetrum v1 Specifications</a></span></dt><dt><span class="section"><a href="#idp54467616">4.
2105 TeleMini v2.0 Specifications
2106 </a></span></dt><dt><span class="section"><a href="#idp54476448">5.
2107 TeleMini v1.0 Specifications
2108 </a></span></dt><dt><span class="section"><a href="#idp54485248">6.
2109 EasyMini Specifications
2110 </a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54435152"></a>1.
2111 TeleMega Specifications
2112 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2113 Recording altimeter for model rocketry.
2114 </p></li><li class="listitem"><p>
2115 Supports dual deployment and four auxiliary pyro channels
2116 (a total of 6 events).
2117 </p></li><li class="listitem"><p>
2118 70cm 40mW ham-band transceiver for telemetry down-link.
2119 </p></li><li class="listitem"><p>
2120 Barometric pressure sensor good to 100k feet MSL.
2121 </p></li><li class="listitem"><p>
2122 1-axis high-g accelerometer for motor characterization, capable of
2124 </p></li><li class="listitem"><p>
2125 9-axis IMU including integrated 3-axis accelerometer,
2126 3-axis gyroscope and 3-axis magnetometer.
2127 </p></li><li class="listitem"><p>
2128 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
2129 </p></li><li class="listitem"><p>
2130 On-board 8 Megabyte non-volatile memory for flight data storage.
2131 </p></li><li class="listitem"><p>
2132 USB interface for battery charging, configuration, and data recovery.
2133 </p></li><li class="listitem"><p>
2134 Fully integrated support for Li-Po rechargeable batteries.
2135 </p></li><li class="listitem"><p>
2136 Can use either main system Li-Po or optional separate pyro battery
2138 </p></li><li class="listitem"><p>
2139 3.25 x 1.25 inch board designed to fit inside 38mm air-frame coupler tube.
2140 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54446496"></a>2.
2141 TeleMetrum v2 Specifications
2142 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2143 Recording altimeter for model rocketry.
2144 </p></li><li class="listitem"><p>
2145 Supports dual deployment (can fire 2 ejection charges).
2146 </p></li><li class="listitem"><p>
2147 70cm, 40mW ham-band transceiver for telemetry down-link.
2148 </p></li><li class="listitem"><p>
2149 Barometric pressure sensor good to 100k feet MSL.
2150 </p></li><li class="listitem"><p>
2151 1-axis high-g accelerometer for motor characterization, capable of
2153 </p></li><li class="listitem"><p>
2154 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
2155 </p></li><li class="listitem"><p>
2156 On-board 8 Megabyte non-volatile memory for flight data storage.
2157 </p></li><li class="listitem"><p>
2158 USB interface for battery charging, configuration, and data recovery.
2159 </p></li><li class="listitem"><p>
2160 Fully integrated support for Li-Po rechargeable batteries.
2161 </p></li><li class="listitem"><p>
2162 Uses Li-Po to fire e-matches, can be modified to support
2163 optional separate pyro battery if needed.
2164 </p></li><li class="listitem"><p>
2165 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
2166 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54457056"></a>3. TeleMetrum v1 Specifications</h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2167 Recording altimeter for model rocketry.
2168 </p></li><li class="listitem"><p>
2169 Supports dual deployment (can fire 2 ejection charges).
2170 </p></li><li class="listitem"><p>
2171 70cm, 10mW ham-band transceiver for telemetry down-link.
2172 </p></li><li class="listitem"><p>
2173 Barometric pressure sensor good to 45k feet MSL.
2174 </p></li><li class="listitem"><p>
2175 1-axis high-g accelerometer for motor characterization, capable of
2176 +/- 50g using default part.
2177 </p></li><li class="listitem"><p>
2178 On-board, integrated GPS receiver with 5Hz update rate capability.
2179 </p></li><li class="listitem"><p>
2180 On-board 1 megabyte non-volatile memory for flight data storage.
2181 </p></li><li class="listitem"><p>
2182 USB interface for battery charging, configuration, and data recovery.
2183 </p></li><li class="listitem"><p>
2184 Fully integrated support for Li-Po rechargeable batteries.
2185 </p></li><li class="listitem"><p>
2186 Uses Li-Po to fire e-matches, can be modified to support
2187 optional separate pyro battery if needed.
2188 </p></li><li class="listitem"><p>
2189 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
2190 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54467616"></a>4.
2191 TeleMini v2.0 Specifications
2192 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2193 Recording altimeter for model rocketry.
2194 </p></li><li class="listitem"><p>
2195 Supports dual deployment (can fire 2 ejection charges).
2196 </p></li><li class="listitem"><p>
2197 70cm, 10mW ham-band transceiver for telemetry down-link.
2198 </p></li><li class="listitem"><p>
2199 Barometric pressure sensor good to 100k feet MSL.
2200 </p></li><li class="listitem"><p>
2201 On-board 1 megabyte non-volatile memory for flight data storage.
2202 </p></li><li class="listitem"><p>
2203 USB interface for configuration, and data recovery.
2204 </p></li><li class="listitem"><p>
2205 Support for Li-Po rechargeable batteries (using an
2206 external charger), or any 3.7-15V external battery.
2207 </p></li><li class="listitem"><p>
2208 Uses Li-Po to fire e-matches, can be modified to support
2209 optional separate pyro battery if needed.
2210 </p></li><li class="listitem"><p>
2211 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
2212 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54476448"></a>5.
2213 TeleMini v1.0 Specifications
2214 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2215 Recording altimeter for model rocketry.
2216 </p></li><li class="listitem"><p>
2217 Supports dual deployment (can fire 2 ejection charges).
2218 </p></li><li class="listitem"><p>
2219 70cm, 10mW ham-band transceiver for telemetry down-link.
2220 </p></li><li class="listitem"><p>
2221 Barometric pressure sensor good to 45k feet MSL.
2222 </p></li><li class="listitem"><p>
2223 On-board 5 kilobyte non-volatile memory for flight data storage.
2224 </p></li><li class="listitem"><p>
2225 RF interface for configuration, and data recovery.
2226 </p></li><li class="listitem"><p>
2227 Support for Li-Po rechargeable batteries, using an external charger.
2228 </p></li><li class="listitem"><p>
2229 Uses Li-Po to fire e-matches, can be modified to support
2230 optional separate pyro battery if needed.
2231 </p></li><li class="listitem"><p>
2232 1.5 x .5 inch board designed to fit inside 18mm air-frame coupler tube.
2233 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54485248"></a>6.
2234 EasyMini Specifications
2235 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2236 Recording altimeter for model rocketry.
2237 </p></li><li class="listitem"><p>
2238 Supports dual deployment (can fire 2 ejection charges).
2239 </p></li><li class="listitem"><p>
2240 Barometric pressure sensor good to 100k feet MSL.
2241 </p></li><li class="listitem"><p>
2242 On-board 1 megabyte non-volatile memory for flight data storage.
2243 </p></li><li class="listitem"><p>
2244 USB interface for configuration, and data recovery.
2245 </p></li><li class="listitem"><p>
2246 Support for Li-Po rechargeable batteries (using an
2247 external charger), or any 3.7-15V external battery.
2248 </p></li><li class="listitem"><p>
2249 Uses Li-Po to fire e-matches, can be modified to support
2250 optional separate pyro battery if needed.
2251 </p></li><li class="listitem"><p>
2252 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
2253 </p></li></ul></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp54493360"></a>Chapter 12. FAQ</h1></div></div></div><p>
2254 <span class="emphasis"><em>TeleMetrum seems to shut off when disconnected from the
2255 computer.</em></span>
2256 Make sure the battery is adequately charged. Remember the
2257 unit will pull more power than the USB port can deliver before the
2258 GPS enters “locked” mode. The battery charges best when TeleMetrum
2261 <span class="emphasis"><em>It's impossible to stop the TeleDongle when it's in “p” mode, I have
2262 to unplug the USB cable? </em></span>
2263 Make sure you have tried to “escape out” of
2264 this mode. If this doesn't work the reboot procedure for the
2265 TeleDongle *is* to simply unplug it. 'cu' however will retain it's
2266 outgoing buffer IF your “escape out” ('~~') does not work.
2267 At this point using either 'ao-view' (or possibly
2268 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
2271 <span class="emphasis"><em>The amber LED (on the TeleMetrum) lights up when both
2272 battery and USB are connected. Does this mean it's charging?
2274 Yes, the yellow LED indicates the charging at the 'regular' rate.
2275 If the led is out but the unit is still plugged into a USB port,
2276 then the battery is being charged at a 'trickle' rate.
2278 <span class="emphasis"><em>There are no “dit-dah-dah-dit” sound or lights like the manual
2279 mentions?</em></span>
2280 That's the “pad” mode. Weak batteries might be the problem.
2281 It is also possible that the flight computer is horizontal and the
2283 is instead a “dit-dit” meaning 'idle'. For TeleMini, it's possible that
2284 it received a command packet which would have left it in “pad” mode.
2286 <span class="emphasis"><em>How do I save flight data?</em></span>
2287 Live telemetry is written to file(s) whenever AltosUI is connected
2288 to the TeleDongle. The file area defaults to ~/TeleMetrum
2289 but is easily changed using the menus in AltosUI. The files that
2290 are written end in '.telem'. The after-flight
2291 data-dumped files will end in .eeprom and represent continuous data
2292 unlike the .telem files that are subject to losses
2293 along the RF data path.
2294 See the above instructions on what and how to save the eeprom stored
2295 data after physically retrieving your altimeter. Make sure to save
2296 the on-board data after each flight; while the TeleMetrum can store
2297 multiple flights, you never know when you'll lose the altimeter...
2298 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp54502208"></a>Appendix A. Notes for Older Software</h1></div></div></div><p>
2299 <span class="emphasis"><em>
2300 Before AltosUI was written, using Altus Metrum devices required
2301 some finesse with the Linux command line. There was a limited
2302 GUI tool, ao-view, which provided functionality similar to the
2303 Monitor Flight window in AltosUI, but everything else was a
2304 fairly 80's experience. This appendix includes documentation for
2305 using that software.
2308 Both TeleMetrum and TeleDongle can be directly communicated
2309 with using USB ports. The first thing you should try after getting
2310 both units plugged into to your computer's USB port(s) is to run
2311 'ao-list' from a terminal-window to see what port-device-name each
2312 device has been assigned by the operating system.
2313 You will need this information to access the devices via their
2314 respective on-board firmware and data using other command line
2315 programs in the AltOS software suite.
2317 TeleMini can be communicated with through a TeleDongle device
2318 over the radio link. When first booted, TeleMini listens for a
2319 TeleDongle device and if it receives a packet, it goes into
2320 'idle' mode. Otherwise, it goes into 'pad' mode and waits to be
2321 launched. The easiest way to get it talking is to start the
2322 communication link on the TeleDongle and the power up the
2325 To access the device's firmware for configuration you need a terminal
2326 program such as you would use to talk to a modem. The software
2327 authors prefer using the program 'cu' which comes from the UUCP package
2328 on most Unix-like systems such as Linux. An example command line for
2329 cu might be 'cu -l /dev/ttyACM0', substituting the correct number
2330 indicated from running the
2331 ao-list program. Another reasonable terminal program for Linux is
2332 'cutecom'. The default 'escape'
2333 character used by CU (i.e. the character you use to
2334 issue commands to cu itself instead of sending the command as input
2335 to the connected device) is a '~'. You will need this for use in
2336 only two different ways during normal operations. First is to exit
2337 the program by sending a '~.' which is called a 'escape-disconnect'
2338 and allows you to close-out from 'cu'. The
2339 second use will be outlined later.
2341 All of the Altus Metrum devices share the concept of a two level
2342 command set in their firmware.
2343 The first layer has several single letter commands. Once
2344 you are using 'cu' (or 'cutecom') sending (typing) a '?'
2345 returns a full list of these
2346 commands. The second level are configuration sub-commands accessed
2347 using the 'c' command, for
2348 instance typing 'c?' will give you this second level of commands
2349 (all of which require the
2350 letter 'c' to access). Please note that most configuration options
2351 are stored only in Flash memory; TeleDongle doesn't provide any storage
2352 for these options and so they'll all be lost when you unplug it.
2354 Try setting these configuration ('c' or second level menu) values. A good
2355 place to start is by setting your call sign. By default, the boards
2356 use 'N0CALL' which is cute, but not exactly legal!
2357 Spend a few minutes getting comfortable with the units, their
2358 firmware, and 'cu' (or possibly 'cutecom').
2359 For instance, try to send
2360 (type) a 'c r 2' and verify the channel change by sending a 'c s'.
2361 Verify you can connect and disconnect from the units while in your
2362 terminal program by sending the escape-disconnect mentioned above.
2364 To set the radio frequency, use the 'c R' command to specify the
2365 radio transceiver configuration parameter. This parameter is computed
2366 using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
2367 the standard calibration reference frequency, 'S', (normally 434.550MHz):
2368 </p><pre class="programlisting">
2371 Round the result to the nearest integer value.
2372 As with all 'c' sub-commands, follow this with a 'c w' to write the
2373 change to the parameter block in the on-board flash on
2374 your altimeter board if you want the change to stay in place across reboots.
2376 To set the apogee delay, use the 'c d' command.
2377 As with all 'c' sub-commands, follow this with a 'c w' to write the
2378 change to the parameter block in the on-board DataFlash chip.
2380 To set the main deployment altitude, use the 'c m' command.
2381 As with all 'c' sub-commands, follow this with a 'c w' to write the
2382 change to the parameter block in the on-board DataFlash chip.
2384 To calibrate the radio frequency, connect the UHF antenna port to a
2385 frequency counter, set the board to 434.550MHz, and use the 'C'
2386 command to generate a CW carrier. Wait for the transmitter temperature
2387 to stabilize and the frequency to settle down.
2388 Then, divide 434.550 MHz by the
2389 measured frequency and multiply by the current radio cal value show
2390 in the 'c s' command. For an unprogrammed board, the default value
2391 is 1186611 for cc1111 based products and 7119667 for cc1120
2392 based products. Take the resulting integer and program it using the 'c f'
2393 command. Testing with the 'C' command again should show a carrier
2394 within a few tens of Hertz of the intended frequency.
2395 As with all 'c' sub-commands, follow this with a 'c w' to write the
2396 change to the configuration memory.
2398 Note that the 'reboot' command, which is very useful on the altimeters,
2399 will likely just cause problems with the dongle. The *correct* way
2400 to reset the dongle is just to unplug and re-plug it.
2402 A fun thing to do at the launch site and something you can do while
2403 learning how to use these units is to play with the radio link access
2404 between an altimeter and the TeleDongle. Be aware that you *must* create
2405 some physical separation between the devices, otherwise the link will
2406 not function due to signal overload in the receivers in each device.
2408 Now might be a good time to take a break and read the rest of this
2409 manual, particularly about the two “modes” that the altimeters
2410 can be placed in. TeleMetrum uses the position of the device when booting
2411 up will determine whether the unit is in “pad” or “idle” mode. TeleMini
2412 enters “idle” mode when it receives a command packet within the first 5 seconds
2413 of being powered up, otherwise it enters “pad” mode.
2415 You can access an altimeter in idle mode from the TeleDongle's USB
2416 connection using the radio link
2417 by issuing a 'p' command to the TeleDongle. Practice connecting and
2418 disconnecting ('~~' while using 'cu') from the altimeter. If
2419 you cannot escape out of the “p” command, (by using a '~~' when in
2420 CU) then it is likely that your kernel has issues. Try a newer version.
2422 Using this radio link allows you to configure the altimeter, test
2423 fire e-matches and igniters from the flight line, check pyro-match
2424 continuity and so forth. You can leave the unit turned on while it
2425 is in 'idle mode' and then place the
2426 rocket vertically on the launch pad, walk away and then issue a
2427 reboot command. The altimeter will reboot and start sending data
2428 having changed to the “pad” mode. If the TeleDongle is not receiving
2429 this data, you can disconnect 'cu' from the TeleDongle using the
2430 procedures mentioned above and THEN connect to the TeleDongle from
2431 inside 'ao-view'. If this doesn't work, disconnect from the
2432 TeleDongle, unplug it, and try again after plugging it back in.
2434 In order to reduce the chance of accidental firing of pyrotechnic
2435 charges, the command to fire a charge is intentionally somewhat
2436 difficult to type, and the built-in help is slightly cryptic to
2437 prevent accidental echoing of characters from the help text back at
2438 the board from firing a charge. The command to fire the apogee
2439 drogue charge is 'i DoIt drogue' and the command to fire the main
2440 charge is 'i DoIt main'.
2442 On TeleMetrum, the GPS will eventually find enough satellites, lock in on them,
2443 and 'ao-view' will both auditorily announce and visually indicate
2445 Now you can launch knowing that you have a good data path and
2446 good satellite lock for flight data and recovery. Remember
2447 you MUST tell ao-view to connect to the TeleDongle explicitly in
2448 order for ao-view to be able to receive data.
2450 The altimeters provide RDF (radio direction finding) tones on
2451 the pad, during descent and after landing. These can be used to
2452 locate the rocket using a directional antenna; the signal
2453 strength providing an indication of the direction from receiver to rocket.
2455 TeleMetrum also provides GPS tracking data, which can further simplify
2456 locating the rocket once it has landed. (The last good GPS data
2457 received before touch-down will be on the data screen of 'ao-view'.)
2459 Once you have recovered the rocket you can download the eeprom
2460 contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
2461 either a USB cable or over the radio link using TeleDongle.
2462 And by following the man page for 'ao-postflight' you can create
2463 various data output reports, graphs, and even KML data to see the
2464 flight trajectory in Google-earth. (Moving the viewing angle making
2465 sure to connect the yellow lines while in Google-earth is the proper
2468 As for ao-view.... some things are in the menu but don't do anything
2469 very useful. The developers have stopped working on ao-view to focus
2470 on a new, cross-platform ground station program. So ao-view may or
2471 may not be updated in the future. Mostly you just use
2472 the Log and Device menus. It has a wonderful display of the incoming
2473 flight data and I am sure you will enjoy what it has to say to you
2474 once you enable the voice output!
2475 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp54526032"></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="#idp54527200">1. TeleMega template</a></span></dt><dt><span class="section"><a href="#idp54543168">2. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp54546832">3. TeleMini v2/EasyMini template</a></span></dt><dt><span class="section"><a href="#idp54550512">4. TeleMini v1 template</a></span></dt></dl></div><p>
2476 These images, when printed, provide precise templates for the
2477 mounting holes in Altus Metrum flight computers
2478 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54527200"></a>1. TeleMega template</h2></div></div></div><p>
2479 TeleMega has overall dimensions of 1.250 x 3.250 inches, and
2480 the mounting holes are sized for use with 4-40 or M3 screws.
2481 </p><div class="informalfigure"><div class="mediaobject"><a name="TeleMegaTemplate"></a><object type="image/svg+xml" data="telemega-outline.svg"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54543168"></a>2. TeleMetrum template</h2></div></div></div><p>
2482 TeleMetrum has overall dimensions of 1.000 x 2.750 inches, and the
2483 mounting holes are sized for use with 4-40 or M3 screws.
2484 </p><div class="informalfigure"><div class="mediaobject"><a name="TeleMetrumTemplate"></a><object type="image/svg+xml" data="telemetrum.svg"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54546832"></a>3. TeleMini v2/EasyMini template</h2></div></div></div><p>
2485 TeleMini v2 and EasyMini have overall dimensions of 0.800 x 1.500 inches, and the
2486 mounting holes are sized for use with 4-40 or M3 screws.
2487 </p><div class="informalfigure"><div class="mediaobject"><a name="MiniTemplate"></a><object type="image/svg+xml" data="easymini-outline.svg"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54550512"></a>4. TeleMini v1 template</h2></div></div></div><p>
2488 TeleMini has overall dimensions of 0.500 x 1.500 inches, and the
2489 mounting holes are sized for use with 2-56 or M2 screws.
2490 </p><div class="informalfigure"><div class="mediaobject"><a name="TeleMiniTemplate"></a><object type="image/svg+xml" data="telemini.svg"></object></div></div></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp54554304"></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="#idp54555856">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp54561136">2. TeleMetrum and TeleMega Accelerometers</a></span></dt></dl></div><p>
2491 There are only two calibrations required for TeleMetrum and
2492 TeleMega, and only one for TeleDongle, TeleMini and EasyMini.
2493 All boards are shipped from the factory pre-calibrated, but
2494 the procedures are documented here in case they are ever
2495 needed. Re-calibration is not supported by AltosUI, you must
2496 connect to the board with a serial terminal program and
2497 interact directly with the on-board command interpreter to
2499 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54555856"></a>1. Radio Frequency</h2></div></div></div><p>
2500 The radio frequency is synthesized from a clock based on the
2501 crystal on the board. The actual frequency of this oscillator
2502 must be measured to generate a calibration constant. While our
2504 bandwidth is wide enough to allow boards to communicate even when
2505 their oscillators are not on exactly the same frequency, performance
2506 is best when they are closely matched.
2507 Radio frequency calibration requires a calibrated frequency counter.
2508 Fortunately, once set, the variation in frequency due to aging and
2509 temperature changes is small enough that re-calibration by customers
2510 should generally not be required.
2512 To calibrate the radio frequency, connect the UHF antenna
2513 port to a frequency counter, set the board to 434.550MHz,
2514 and use the 'C' command in the on-board command interpreter
2515 to generate a CW carrier. For USB-enabled boards, this is
2516 best done over USB. For TeleMini v1, note that the only way
2517 to escape the 'C' command is via power cycle since the board
2518 will no longer be listening for commands once it starts
2519 generating a CW carrier.
2521 Wait for the transmitter temperature to stabilize and the frequency
2522 to settle down. Then, divide 434.550 MHz by the
2523 measured frequency and multiply by the current radio cal value show
2524 in the 'c s' command. For an unprogrammed board, the default value
2525 is 1186611. Take the resulting integer and program it using the 'c f'
2526 command. Testing with the 'C' command again should show a carrier
2527 within a few tens of Hertz of the intended frequency.
2528 As with all 'c' sub-commands, follow this with a 'c w' to write the
2529 change to the parameter block in the on-board storage chip.
2531 Note that any time you re-do the radio frequency calibration, the
2532 radio frequency is reset to the default 434.550 Mhz. If you want
2533 to use another frequency, you will have to set that again after
2534 calibration is completed.
2535 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54561136"></a>2. TeleMetrum and TeleMega Accelerometers</h2></div></div></div><p>
2536 While barometric sensors are factory-calibrated,
2537 accelerometers are not, and so each must be calibrated once
2538 installed in a flight computer. Explicitly calibrating the
2539 accelerometers also allows us to load any compatible device.
2540 We perform a two-point calibration using gravity.
2542 To calibrate the acceleration sensor, use the 'c a 0' command. You
2543 will be prompted to orient the board vertically with the UHF antenna
2544 up and press a key, then to orient the board vertically with the
2545 UHF antenna down and press a key. Note that the accuracy of this
2546 calibration depends primarily on how perfectly vertical and still
2547 the board is held during the cal process. As with all 'c'
2548 sub-commands, follow this with a 'c w' to write the
2549 change to the parameter block in the on-board DataFlash chip.
2551 The +1g and -1g calibration points are included in each telemetry
2552 frame and are part of the header stored in onboard flash to be
2553 downloaded after flight. We always store and return raw ADC
2554 samples for each sensor... so nothing is permanently “lost” or
2555 “damaged” if the calibration is poor.
2557 In the unlikely event an accel cal goes badly, it is possible
2558 that TeleMetrum or TeleMega may always come up in 'pad mode'
2559 and as such not be listening to either the USB or radio link.
2560 If that happens, there is a special hook in the firmware to
2561 force the board back in to 'idle mode' so you can re-do the
2562 cal. To use this hook, you just need to ground the SPI clock
2563 pin at power-on. This pin is available as pin 2 on the 8-pin
2564 companion connector, and pin 1 is ground. So either
2565 carefully install a fine-gauge wire jumper between the two
2566 pins closest to the index hole end of the 8-pin connector, or
2567 plug in the programming cable to the 8-pin connector and use
2568 a small screwdriver or similar to short the two pins closest
2569 to the index post on the 4-pin end of the programming cable,
2570 and power up the board. It should come up in 'idle mode'
2571 (two beeps), allowing a re-cal.
2572 </p></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp54567264"></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="idp54567904"></a>Version 1.3.1</h2></div></div></div><p>
2573 Version 1.3.1 is a minor release. It improves support for TeleMega,
2574 TeleMetrum v2.0, TeleMini v2.0 and EasyMini.
2576 AltOS Firmware Changes
2577 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2578 Improve sensor boot code. If sensors fail to self-test, the
2579 device will still boot up and check for pad/idle modes. If
2580 in idle mode, the device will warn the user with a distinct
2581 beep, if in Pad mode, the unit will operate as best it
2582 can. Also, the Z-axis accelerometer now uses the factory
2583 calibration values instead of re-calibrating on the pad each
2584 time. This avoids accidental boost detect when moving the
2585 device around while in Pad mode.
2586 </p></li><li class="listitem"><p>
2587 Fix antenna-down mode accelerometer configuration. Antenna
2588 down mode wasn't working because the accelerometer
2589 calibration values were getting re-computed incorrectly in
2591 </p></li><li class="listitem"><p>
2592 Improved APRS mode. Now uses compressed position format for
2593 smaller data size, improved precision and to include
2594 altitude data as well as latitude and longitude. Also added
2595 battery and pyro voltage reports in the APRS comment field
2596 so you can confirm that the unit is ready for launch.
2597 </p></li></ul></div><p>
2600 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2601 Display additional TeleMega sensor values in real
2602 units. Make all of these values available for
2603 plotting. Display TeleMega orientation value in the Ascent
2605 </p></li><li class="listitem"><p>
2606 Support additional TeleMega pyro channels in the Fire
2607 Igniter dialog. This lets you do remote testing of all of
2608 the channels, rather than just Apogee and Main.
2609 </p></li><li class="listitem"><p>
2610 Limit data rate when downloading satellite images from
2611 Google to make sure we stay within their limits so that all
2612 of the map tiles download successfully.
2613 </p></li></ul></div><p>
2614 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54569504"></a>Version 1.3</h2></div></div></div><p>
2615 Version 1.3 is a major release. It adds support for TeleMega,
2616 TeleMetrum v2.0, TeleMini v2.0 and EasyMini.
2618 AltOS Firmware Changes
2619 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2620 Add STM32L processor support. This includes enhancements to
2621 the scheduler to support products with many threads.
2622 </p></li><li class="listitem"><p>
2623 Add NXP LPC11U14 processor support.
2624 </p></li><li class="listitem"><p>
2625 Support additional pyro channels. These are configurable
2626 through the UI to handle air starts, staging, additional
2627 recovery events and external devices such as cameras.
2628 </p></li><li class="listitem"><p>
2629 Add 3-axis gyro support for orientation tracking. This
2630 integrates the gyros to compute the angle from vertical during
2631 flight, allowing the additional pyro events to be controlled
2633 </p></li><li class="listitem"><p>
2634 Many more device drivers, including u-Blox Max 7Q GPS,
2635 Freescale MMA6555 digital single-axis accelerometer,
2636 Invensense MPU6000 3-axis accelerometer + 3 axis gyro,
2637 Honeywell HMC5883 3-axis magnetic sensor and the TI CC1120 and
2638 CC115L digital FM transceivers
2639 </p></li></ul></div><p>
2642 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2643 Support TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini telemetry and log formats.
2644 </p></li><li class="listitem"><p>
2645 Use preferred units for main deployment height configuration,
2646 instead of always doing configuration in meters.
2647 </p></li></ul></div><p>
2649 MicroPeak UI changes
2650 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2651 Add 'Download' button to menu bar.
2652 </p></li><li class="listitem"><p>
2653 Save the last log directory and offer that as the default for new downloads
2654 </p></li></ul></div><p>
2655 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54571104"></a>Version 1.2.1</h2></div></div></div><p>
2656 Version 1.2.1 is a minor release. It adds support for TeleBT and
2657 the AltosDroid application, provides several new features in
2658 AltosUI and fixes some bugs in the AltOS firmware.
2660 AltOS Firmware Changes
2661 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2662 Add support for TeleBT
2663 </p></li><li class="listitem"><p>
2664 In TeleMini recovery mode (when booted with the outer two
2665 debug pins connected together), the radio parameters are also
2666 set back to defaults (434.550MHz, N0CALL, factory radio cal).
2667 </p></li><li class="listitem"><p>
2668 Add support for reflashing the SkyTraq GPS chips. This
2669 requires special host-side code which currently only exists
2671 </p></li><li class="listitem"><p>
2672 Correct Kalman filter model error covariance matrix. The
2673 values used previously assumed continuous measurements instead
2674 of discrete measurements.
2675 </p></li><li class="listitem"><p>
2676 Fix some bugs in the USB driver for TeleMetrum and TeleDongle
2677 that affected Windows users.
2678 </p></li><li class="listitem"><p>
2679 Adjusted the automatic gain control parameters that affect
2680 receive performance for TeleDongle. Field tests indicate that this
2681 may improve receive performance somewhat.
2682 </p></li></ul></div><p>
2685 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2686 Handle missing GPS lock in 'Descent' tab. Previously, if the
2687 GPS position of the pad was unknown, an exception would be
2688 raised, breaking the Descent tab contents.
2689 </p></li><li class="listitem"><p>
2690 Improve the graph, adding tool-tips to show values near the
2691 cursor and making the displayed set of values configurable,
2692 adding all of the flight data as options while leaving the
2693 default settings alone so that the graph starts by showing
2694 height, speed and acceleration.
2695 </p></li><li class="listitem"><p>
2696 Make the initial position of the AltosUI top level window
2697 configurable. Along with this change, the other windows will
2698 pop up at 'sensible' places now, instead of on top of one
2700 </p></li><li class="listitem"><p>
2701 Add callsign to Monitor idle window and connecting
2702 dialogs. This makes it clear which callsign is being used so
2703 that the operator will be aware that it must match the flight
2704 computer value or no communication will work.
2705 </p></li><li class="listitem"><p>
2706 When downloading flight data, display the block number so that
2707 the user has some sense of progress. Unfortunately, we don't
2708 know how many blocks will need to be downloaded, but at least
2709 it isn't just sitting there doing nothing for a long time.
2710 </p></li><li class="listitem"><p>
2711 Add GPS data and a map to the graph window. This lets you see
2712 a complete summary of the flight without needing to 'replay'
2714 </p></li></ul></div><p>
2715 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54572608"></a>Version 1.2</h2></div></div></div><p>
2716 Version 1.2 is a major release. It adds support for MicroPeak and
2717 the MicroPeak USB adapter.
2719 AltOS Firmware Changes
2720 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2721 Add MicroPeak support. This includes support for the ATtiny85
2722 processor and adaptations to the core code to allow for
2723 devices too small to run the multi-tasking scheduler.
2724 </p></li></ul></div><p>
2726 MicroPeak UI changes
2727 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2728 Added this new application
2729 </p></li></ul></div><p>
2731 Distribution Changes
2732 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2733 Distribute Mac OS X packages in disk image ('.dmg') format to
2734 greatly simplify installation.
2735 </p></li><li class="listitem"><p>
2736 Provide version numbers for the shared Java libraries to
2737 ensure that upgrades work properly, and to allow for multiple
2738 Altus Metrum software packages to be installed in the same
2739 directory at the same time.
2740 </p></li></ul></div><p>
2741 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54574112"></a>Version 1.1.1</h2></div></div></div><p>
2742 Version 1.1.1 is a bug-fix release. It fixes a couple of bugs in
2743 AltosUI and one firmware bug that affects TeleMetrum version 1.0
2744 boards. Thanks to Bob Brown for help diagnosing the Google Earth
2745 file export issue, and for suggesting the addition of the Ground
2746 Distance value in the Descent tab.
2748 AltOS Firmware Changes
2749 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2750 TeleMetrum v1.0 boards use the AT45DB081D flash memory part to
2751 store flight data, which is different from later TeleMetrum
2752 boards. The AltOS v1.1 driver for this chip couldn't erase
2753 memory, leaving it impossible to delete flight data or update
2754 configuration values. This bug doesn't affect newer TeleMetrum
2755 boards, and it doesn't affect the safety of rockets flying
2756 version 1.1 firmware.
2757 </p></li></ul></div><p>
2760 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2761 Creating a Google Earth file (KML) from on-board flight data
2762 (EEPROM) would generate an empty file. The code responsible
2763 for reading the EEPROM file wasn't ever setting the GPS valid
2764 bits, and so the KML export code thought there was no GPS data
2766 </p></li><li class="listitem"><p>
2767 The “Landed” tab was displaying all values in metric units,
2768 even when AltosUI was configured to display imperial
2769 units. Somehow I just missed this tab when doing the units stuff.
2770 </p></li><li class="listitem"><p>
2771 The “Descent” tab displays the range to the rocket, which is a
2772 combination of the over-the-ground distance to the rockets
2773 current latitude/longitude and the height of the rocket. As
2774 such, it's useful for knowing how far away the rocket is, but
2775 difficult to use when estimating where the rocket might
2776 eventually land. A new “Ground Distance” field has been added
2777 which displays the distance to a spot right underneath the
2779 </p></li><li class="listitem"><p>
2780 Sensor data wasn't being displayed for TeleMini flight
2781 computers in Monitor Idle mode, including things like battery
2782 voltage. The code that picked which kinds of data to fetch
2783 from the flight computer was missing a check for TeleMini when
2784 deciding whether to fetch the analog sensor data.
2785 </p></li></ul></div><p>
2786 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54575616"></a>Version 1.1</h2></div></div></div><p>
2787 Version 1.1 is a minor release. It provides a few new features in AltosUI
2788 and the AltOS firmware and fixes bugs.
2790 AltOS Firmware Changes
2791 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2792 Add apogee-lockout value. Overrides the apogee detection logic to
2793 prevent incorrect apogee charge firing.
2794 </p></li><li class="listitem"><p>
2795 Fix a bug where the data reported in telemetry packets was
2797 </p></li><li class="listitem"><p>
2798 Force the radio frequency to 434.550MHz when the debug clock
2799 pin is connected to ground at boot time. This provides a way
2800 to talk to a TeleMini which is configured to some unknown frequency.
2801 </p></li><li class="listitem"><p>
2802 Provide RSSI values for Monitor Idle mode. This makes it easy to check radio
2803 range without needing to go to flight mode.
2804 </p></li><li class="listitem"><p>
2805 Fix a bug which caused the old received telemetry packets to
2806 be retransmitted over the USB link when the radio was turned
2808 </p></li></ul></div><p>
2811 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2812 Fix a bug that caused GPS ready to happen too quickly. The
2813 software was using every telemetry packet to signal new GPS
2814 data, which caused GPS ready to be signalled after 10 packets
2815 instead of 10 GPS updates.
2816 </p></li><li class="listitem"><p>
2817 Fix Google Earth data export to work with recent versions. The
2818 google earth file loading code got a lot pickier, requiring
2819 some minor white space changes in the export code.
2820 </p></li><li class="listitem"><p>
2821 Make the look-n-feel configurable, providing a choice from
2822 the available options.
2823 </p></li><li class="listitem"><p>
2824 Add an 'Age' element to mark how long since a telemetry packet
2825 has been received. Useful to quickly gauge whether
2826 communications with the rocket are still active.
2827 </p></li><li class="listitem"><p>
2828 Add 'Configure Ground Station' dialog to set the radio
2829 frequency used by a particular TeleDongle without having to go
2830 through the flight monitor UI.
2831 </p></li><li class="listitem"><p>
2832 Add configuration for the new apogee-lockout value. A menu provides a list of
2833 reasonable values, or the value can be set by hand.
2834 </p></li><li class="listitem"><p>
2835 Changed how flight data are downloaded. Now there's an initial
2836 dialog asking which flights to download, and after that
2837 finishes, a second dialog comes up asking which flights to delete.
2838 </p></li><li class="listitem"><p>
2839 Re-compute time spent in each state for the flight graph; this
2840 figures out the actual boost and landing times instead of
2841 using the conservative values provide by the flight
2842 electronics. This improves the accuracy of the boost
2843 acceleration and main descent rate computations.
2844 </p></li><li class="listitem"><p>
2845 Make AltosUI run on Mac OS Lion. The default Java heap space
2846 was dramatically reduced for this release causing much of the
2847 UI to fail randomly. This most often affected the satellite
2848 mapping download and displays.
2849 </p></li><li class="listitem"><p>
2850 Change how data are displayed in the 'table' tab of the flight
2851 monitoring window. This eliminates entries duplicated from the
2852 header and adds both current altitude and pad altitude, which
2853 are useful in 'Monitor Idle' mode.
2854 </p></li><li class="listitem"><p>
2855 Add Imperial units mode to present data in feet instead of
2857 </p></li></ul></div><p>
2858 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54577120"></a>Version 1.0.1</h2></div></div></div><p>
2859 Version 1.0.1 is a major release, adding support for the TeleMini
2860 device and lots of new AltosUI features
2862 AltOS Firmware Changes
2863 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2864 Add TeleMini v1.0 support. Firmware images for TeleMini are
2865 included in AltOS releases.
2866 </p></li><li class="listitem"><p>
2867 Change telemetry to be encoded in multiple 32-byte packets. This
2868 enables support for TeleMini and other devices without requiring
2869 further updates to the TeleDongle firmware.
2870 </p></li><li class="listitem"><p>
2871 Support operation of TeleMetrum with the antenna pointing
2872 aft. Previous firmware versions required the antenna to be
2873 pointing upwards, now there is a configuration option allowing
2874 the antenna to point aft, to aid installation in some airframes.
2875 </p></li><li class="listitem"><p>
2876 Ability to disable telemetry. For airframes where an antenna
2877 just isn't possible, or where radio transmissions might cause
2878 trouble with other electronics, there's a configuration option
2879 to disable all telemetry. Note that the board will still
2880 enable the radio link in idle mode.
2881 </p></li><li class="listitem"><p>
2882 Arbitrary frequency selection. The radios in Altus Metrum
2883 devices can be programmed to a wide range of frequencies, so
2884 instead of limiting devices to 10 pre-selected 'channels', the
2885 new firmware allows the user to choose any frequency in the
2886 70cm band. Note that the RF matching circuit on the boards is
2887 tuned for around 435MHz, so frequencies far from that may
2888 reduce the available range.
2889 </p></li><li class="listitem"><p>
2890 Kalman-filter based flight-tracking. The model based sensor
2891 fusion approach of a Kalman filter means that AltOS now
2892 computes apogee much more accurately than before, generally
2893 within a fraction of a second. In addition, this approach
2894 allows the baro-only TeleMini device to correctly identify
2895 Mach transitions, avoiding the error-prone selection of a Mach
2897 </p></li></ul></div><p>
2900 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2901 Wait for altimeter when using packet mode. Instead of quicly
2902 timing out when trying to initialize a packet mode
2903 configuration connection, AltosUI now waits indefinitely for
2904 the remote device to appear, providing a cancel button should
2905 the user get bored. This is necessary as the TeleMini can only
2906 be placed in "Idle" mode if AltosUI is polling it.
2907 </p></li><li class="listitem"><p>
2908 Add main/apogee voltage graphs to the data plot. This provides
2909 a visual indication if the igniters fail before being fired.
2910 </p></li><li class="listitem"><p>
2911 Scan for altimeter devices by watching the defined telemetry
2912 frequencies. This avoids the problem of remembering what
2913 frequency a device was configured to use, which is especially
2914 important with TeleMini which does not include a USB connection.
2915 </p></li><li class="listitem"><p>
2916 Monitor altimeter state in "Idle" mode. This provides much of
2917 the information presented in the "Pad" dialog from the Monitor
2918 Flight command, monitoring the igniters, battery and GPS
2919 status withing requiring the flight computer to be armed and
2921 </p></li><li class="listitem"><p>
2922 Pre-load map images from home. For those launch sites which
2923 don't provide free Wi-Fi, this allows you to download the
2924 necessary satellite images given the location of the launch
2925 site. A list of known launch sites is maintained at
2926 altusmetrum.org which AltosUI downloads to populate a menu; if
2927 you've got a launch site not on that list, please send the
2928 name of it, latitude and longitude along with a link to the
2929 web site of the controlling club to the altusmetrum mailing list.
2930 </p></li><li class="listitem"><p>
2931 Flight statistics are now displayed in the Graph data
2932 window. These include max height/speed/accel, average descent
2933 rates and a few other bits of information. The Graph Data
2934 window can now be reached from the 'Landed' tab in the Monitor
2935 Flight window so you can immediately see the results of a
2937 </p></li></ul></div><p>
2938 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54578624"></a>Version 0.9.2</h2></div></div></div><p>
2939 Version 0.9.2 is an AltosUI bug-fix release, with no firmware changes.
2940 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2941 Fix plotting problems due to missing file in the Mac OS install image.
2942 </p></li><li class="listitem"><p>
2943 Always read whole eeprom blocks, mark empty records invalid, display parsing errors to user.
2944 </p></li><li class="listitem"><p>
2945 Add software version to Configure AltosUI dialog
2946 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54580128"></a>Version 0.9</h2></div></div></div><p>
2947 Version 0.9 adds a few new firmware features and accompanying
2948 AltosUI changes, along with new hardware support.
2949 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2950 Support for TeleMetrum v1.1 hardware. Sources for the flash
2951 memory part used in v1.0 dried up, so v1.1 uses a different part
2952 which required a new driver and support for explicit flight log
2954 </p></li><li class="listitem"><p>
2955 Multiple flight log support. This stores more than one flight
2956 log in the on-board flash memory. It also requires the user to
2957 explicitly erase flights so that you won't lose flight logs just
2958 because you fly the same board twice in one day.
2959 </p></li><li class="listitem"><p>
2960 Telemetry support for devices with serial number >=
2961 256. Previous versions used a telemetry packet format that
2962 provided only 8 bits for the device serial number. This change
2963 requires that both ends of the telemetry link be running the 0.9
2964 firmware or they will not communicate.
2965 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54581632"></a>Version 0.8</h2></div></div></div><p>
2966 Version 0.8 offers a major upgrade in the AltosUI
2967 interface. Significant new features include:
2968 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2969 Post-flight graphing tool. This lets you explore the behaviour
2970 of your rocket after flight with a scroll-able and zoom-able
2971 chart showing the altitude, speed and acceleration of the
2972 airframe along with events recorded by the flight computer. You
2973 can export graphs to PNG files, or print them directly.
2974 </p></li><li class="listitem"><p>
2975 Real-time moving map which overlays the in-progress flight on
2976 satellite imagery fetched from Google Maps. This lets you see in
2977 pictures where your rocket has landed, allowing you to plan
2978 recovery activities more accurately.
2979 </p></li><li class="listitem"><p>
2980 Wireless recovery system testing. Prep your rocket for flight
2981 and test fire the deployment charges to make sure things work as
2982 expected. All without threading wires through holes in your
2984 </p></li><li class="listitem"><p>
2985 Optimized flight status displays. Each flight state now has it's
2986 own custom 'tab' in the flight monitoring window so you can
2987 focus on the most important details. Pre-flight, the system
2988 shows a set of red/green status indicators for battery voltage,
2989 apogee/main igniter continutity and GPS reception. Wait until
2990 they're all green and your rocket is ready for flight. There are
2991 also tabs for ascent, descent and landing along with the
2992 original tabular view of the data.
2993 </p></li><li class="listitem"><p>
2994 Monitor multiple flights simultaneously. If you have more than
2995 one TeleDongle, you can monitor a flight with each one on the
2997 </p></li><li class="listitem"><p>
2998 Automatic flight monitoring at startup. Plug TeleDongle into the
2999 machine before starting AltosUI and it will automatically
3000 connect to it and prepare to monitor a flight.
3001 </p></li><li class="listitem"><p>
3002 Exports Google Earth flight tracks. Using the Keyhole Markup
3003 Language (.kml) file format, this provides a 3D view of your
3004 rocket flight through the Google Earth program.
3005 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp54583136"></a>Version 0.7.1</h2></div></div></div><p>
3006 Version 0.7.1 is the first release containing our new cross-platform Java-based user interface. AltosUI can:
3007 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
3008 Receive and log telemetry from a connected TeleDongle
3009 device. All data received is saved to log files named with the
3010 current date and the connected rocket serial and flight
3011 numbers. There is no mode in which telemetry data will not be
3013 </p></li><li class="listitem"><p>
3014 Download logged data from TeleMetrum devices, either through a
3015 direct USB connection or over the air through a TeleDongle
3017 </p></li><li class="listitem"><p>
3018 Configure a TeleMetrum device, setting the radio channel,
3019 callsign, apogee delay and main deploy height. This can be done
3020 through either a USB connection or over a radio link via a
3022 </p></li><li class="listitem"><p>
3023 Replay a flight in real-time. This takes a saved telemetry log
3024 or eeprom download and replays it through the user interface so
3025 you can relive your favorite rocket flights.
3026 </p></li><li class="listitem"><p>
3027 Reprogram Altus Metrum devices. Using an Altus Metrum device
3028 connected via USB, another Altus Metrum device can be
3029 reprogrammed using the supplied programming cable between the
3031 </p></li><li class="listitem"><p>
3032 Export Flight data to a comma-separated-values file. This takes
3033 either telemetry or on-board flight data and generates data
3034 suitable for use in external applications. All data is exported
3035 using standard units so that no device-specific knowledge is
3036 needed to handle the data.
3037 </p></li><li class="listitem"><p>
3038 Speak to you during the flight. Instead of spending the flight
3039 hunched over your laptop looking at the screen, enjoy the view
3040 while the computer tells you what’s going on up there. During
3041 ascent, you hear the current flight state and altitude
3042 information. During descent, you get azimuth, elevation and
3043 range information to try and help you find your rocket in the
3044 air. Once on the ground, the direction and distance are
3046 </p></li></ul></div></div></div></div></body></html>
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