1 <?xml version="1.0" encoding="utf-8"?>
2 <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3 "/usr/share/xml/docbook/schema/dtd/4.5/docbookx.dtd">
5 <title>The Altus Metrum System</title>
6 <subtitle>An Owner's Manual for Altus Metrum Rocketry Electronics</subtitle>
9 <firstname>Bdale</firstname>
10 <surname>Garbee</surname>
13 <firstname>Keith</firstname>
14 <surname>Packard</surname>
17 <firstname>Bob</firstname>
18 <surname>Finch</surname>
21 <firstname>Anthony</firstname>
22 <surname>Towns</surname>
26 <holder>Bdale Garbee and Keith Packard</holder>
30 <imagedata fileref="../themes/background.png" width="6.0in"/>
35 This document is released under the terms of the
36 <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
37 Creative Commons ShareAlike 3.0
44 <revnumber>1.4.2</revnumber>
45 <date>17 August 2014</date>
47 Minor release fixing some Windows Java installation bugs.
51 <revnumber>1.4.1</revnumber>
52 <date>24 June 2014</date>
54 Minor release fixing some installation bugs.
58 <revnumber>1.4</revnumber>
59 <date>15 June 2014</date>
61 Major release adding TeleGPS support.
65 <revnumber>1.3.2</revnumber>
66 <date>24 January 2014</date>
68 Bug fixes for TeleMega and AltosUI.
72 <revnumber>1.3.1</revnumber>
73 <date>21 January 2014</date>
75 Bug fixes for TeleMega and TeleMetrum v2.0 along with a few
76 small UI improvements.
80 <revnumber>1.3</revnumber>
81 <date>12 November 2013</date>
83 Updated for software version 1.3. Version 1.3 adds support
84 for TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini
85 and fixes bugs in AltosUI and the AltOS firmware.
89 <revnumber>1.2.1</revnumber>
90 <date>21 May 2013</date>
92 Updated for software version 1.2. Version 1.2 adds support
93 for TeleBT and AltosDroid. It also adds a few minor features
94 and fixes bugs in AltosUI and the AltOS firmware.
98 <revnumber>1.2</revnumber>
99 <date>18 April 2013</date>
101 Updated for software version 1.2. Version 1.2 adds support
102 for MicroPeak and the MicroPeak USB interface.
106 <revnumber>1.1.1</revnumber>
107 <date>16 September 2012</date>
109 Updated for software version 1.1.1 Version 1.1.1 fixes a few
110 bugs found in version 1.1.
114 <revnumber>1.1</revnumber>
115 <date>13 September 2012</date>
117 Updated for software version 1.1. Version 1.1 has new
118 features but is otherwise compatible with version 1.0.
122 <revnumber>1.0</revnumber>
123 <date>24 August 2011</date>
125 Updated for software version 1.0. Note that 1.0 represents a
126 telemetry format change, meaning both ends of a link
127 (TeleMetrum/TeleMini and TeleDongle) must be updated or
128 communications will fail.
132 <revnumber>0.9</revnumber>
133 <date>18 January 2011</date>
135 Updated for software version 0.9. Note that 0.9 represents a
136 telemetry format change, meaning both ends of a link (TeleMetrum and
137 TeleDongle) must be updated or communications will fail.
141 <revnumber>0.8</revnumber>
142 <date>24 November 2010</date>
143 <revremark>Updated for software version 0.8 </revremark>
148 <title>Acknowledgments</title>
150 Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing “The
151 Mere-Mortals Quick Start/Usage Guide to the Altus Metrum Starter
152 Kit” which formed the basis of the original Getting Started chapter
153 in this manual. Bob was one of our first customers for a production
154 TeleMetrum, and his continued enthusiasm and contributions
155 are immensely gratifying and highly appreciated!
158 And thanks to Anthony (AJ) Towns for major contributions including
159 the AltosUI graphing and site map code and associated documentation.
160 Free software means that our customers and friends can become our
161 collaborators, and we certainly appreciate this level of
165 Have fun using these products, and we hope to meet all of you
166 out on the rocket flight line somewhere.
169 NAR #87103, TRA #12201
171 Keith Packard, KD7SQG
172 NAR #88757, TRA #12200
177 <title>Introduction and Overview</title>
179 Welcome to the Altus Metrum community! Our circuits and software reflect
180 our passion for both hobby rocketry and Free Software. We hope their
181 capabilities and performance will delight you in every way, but by
182 releasing all of our hardware and software designs under open licenses,
183 we also hope to empower you to take as active a role in our collective
187 The first device created for our community was TeleMetrum, a dual
188 deploy altimeter with fully integrated GPS and radio telemetry
189 as standard features, and a “companion interface” that will
190 support optional capabilities in the future. The latest version
191 of TeleMetrum, v2.0, has all of the same features but with
192 improved sensors and radio to offer increased performance.
195 Our second device was TeleMini, a dual deploy altimeter with
196 radio telemetry and radio direction finding. The first version
197 of this device was only 13mm by 38mm (½ inch by 1½ inches) and
198 could fit easily in an 18mm air-frame. The latest version, v2.0,
199 includes a beeper, USB data download and extended on-board
200 flight logging, along with an improved barometric sensor.
203 TeleMega is our most sophisticated device, including six pyro
204 channels (four of which are fully programmable), integrated GPS,
205 integrated gyroscopes for staging/air-start inhibit and high
206 performance telemetry.
209 EasyMini is a dual-deploy altimeter with logging and built-in
213 TeleDongle was our first ground station, providing a USB to RF
214 interfaces for communicating with the altimeters. Combined with
215 your choice of antenna and notebook computer, TeleDongle and our
216 associated user interface software form a complete ground
217 station capable of logging and displaying in-flight telemetry,
218 aiding rocket recovery, then processing and archiving flight
219 data for analysis and review.
222 For a slightly more portable ground station experience that also
223 provides direct rocket recovery support, TeleBT offers flight
224 monitoring and data logging using a Bluetooth™ connection between
225 the receiver and an Android device that has the AltosDroid
226 application installed from the Google Play store.
229 More products will be added to the Altus Metrum family over time, and
230 we currently envision that this will be a single, comprehensive manual
231 for the entire product family.
235 <title>Getting Started</title>
237 The first thing to do after you check the inventory of parts in your
238 “starter kit” is to charge the battery.
241 For TeleMetrum and TeleMega, the battery can be charged by plugging it into the
242 corresponding socket of the device and then using the USB
243 cable to plug the flight computer into your computer's USB socket. The
244 on-board circuitry will charge the battery whenever it is plugged
245 in, because the on-off switch does NOT control the
249 On TeleMetrum v1 boards, when the GPS chip is initially
250 searching for satellites, TeleMetrum will consume more current
251 than it pulls from the USB port, so the battery must be
252 attached in order to get satellite lock. Once GPS is locked,
253 the current consumption goes back down enough to enable charging
254 while running. So it's a good idea to fully charge the battery
255 as your first item of business so there is no issue getting and
256 maintaining satellite lock. The yellow charge indicator led
257 will go out when the battery is nearly full and the charger goes
258 to trickle charge. It can take several hours to fully recharge a
259 deeply discharged battery.
262 TeleMetrum v2.0 and TeleMega use a higher power battery charger,
263 allowing them to charge the battery while running the board at
264 maximum power. When the battery is charging, or when the board
265 is consuming a lot of power, the red LED will be lit. When the
266 battery is fully charged, the green LED will be lit. When the
267 battery is damaged or missing, both LEDs will be lit, which
271 The Lithium Polymer TeleMini and EasyMini battery can be charged by
272 disconnecting it from the board and plugging it into a
273 standalone battery charger such as the LipoCharger product
274 included in TeleMini Starter Kits, and connecting that via a USB
275 cable to a laptop or other USB power source.
278 You can also choose to use another battery with TeleMini v2.0
279 and EasyMini, anything supplying between 4 and 12 volts should
280 work fine (like a standard 9V battery), but if you are planning
281 to fire pyro charges, ground testing is required to verify that
282 the battery supplies enough current to fire your chosen e-matches.
285 The other active device in the starter kit is the TeleDongle USB to
286 RF interface. If you plug it in to your Mac or Linux computer it should
287 “just work”, showing up as a serial port device. Windows systems need
288 driver information that is part of the AltOS download to know that the
289 existing USB modem driver will work. We therefore recommend installing
290 our software before plugging in TeleDongle if you are using a Windows
291 computer. If you are using an older version of Linux and are having
292 problems, try moving to a fresher kernel (2.6.33 or newer).
295 Next you should obtain and install the AltOS software. The AltOS
296 distribution includes the AltosUI ground station program, current
298 images for all of the hardware, and a number of standalone
299 utilities that are rarely needed. Pre-built binary packages are
300 available for Linux, Microsoft Windows, and recent MacOSX
301 versions. Full source code and build instructions are also
302 available. The latest version may always be downloaded from
303 <ulink url="http://altusmetrum.org/AltOS"/>.
306 If you're using a TeleBT instead of the TeleDongle, you'll want to
307 install the AltosDroid application from the Google Play store on an
308 Android device. You don't need a data plan to use AltosDroid, but
309 without network access, the Map view will be less useful as it
310 won't contain any map data. You can also use TeleBT connected
311 over USB with your laptop computer; it acts exactly like a
312 TeleDongle. Anywhere this manual talks about TeleDongle, you can
313 also read that as 'and TeleBT when connected via USB'.
317 <title>Handling Precautions</title>
319 All Altus Metrum products are sophisticated electronic devices.
320 When handled gently and properly installed in an air-frame, they
321 will deliver impressive results. However, as with all electronic
322 devices, there are some precautions you must take.
325 The Lithium Polymer rechargeable batteries have an
326 extraordinary power density. This is great because we can fly with
327 much less battery mass than if we used alkaline batteries or previous
328 generation rechargeable batteries... but if they are punctured
329 or their leads are allowed to short, they can and will release their
331 Thus we recommend that you take some care when handling our batteries
332 and consider giving them some extra protection in your air-frame. We
333 often wrap them in suitable scraps of closed-cell packing foam before
334 strapping them down, for example.
337 The barometric sensors used on all of our flight computers are
338 sensitive to sunlight. In normal mounting situations, the baro sensor
339 and all of the other surface mount components
340 are “down” towards whatever the underlying mounting surface is, so
341 this is not normally a problem. Please consider this when designing an
342 installation in an air-frame with a see-through plastic payload bay. It
343 is particularly important to
344 consider this with TeleMini v1.0, both because the baro sensor is on the
345 “top” of the board, and because many model rockets with payload bays
346 use clear plastic for the payload bay! Replacing these with an opaque
347 cardboard tube, painting them, or wrapping them with a layer of masking
348 tape are all reasonable approaches to keep the sensor out of direct
352 The barometric sensor sampling port must be able to “breathe”,
353 both by not being covered by foam or tape or other materials that might
354 directly block the hole on the top of the sensor, and also by having a
355 suitable static vent to outside air.
358 As with all other rocketry electronics, Altus Metrum altimeters must
359 be protected from exposure to corrosive motor exhaust and ejection
364 <title>Altus Metrum Hardware</title>
366 <title>General Usage Instructions</title>
368 Here are general instructions for hooking up an Altus Metrum
369 flight computer. Instructions specific to each model will be
370 found in the section devoted to that model below.
373 To prevent electrical interference from affecting the
374 operation of the flight computer, it's important to always
375 twist pairs of wires connected to the board. Twist the switch
376 leads, the pyro leads and the battery leads. This reduces
377 interference through a mechanism called common mode rejection.
380 <title>Hooking Up Lithium Polymer Batteries</title>
382 All Altus Metrum flight computers have a two pin JST PH
383 series connector to connect up a single-cell Lithium Polymer
384 cell (3.7V nominal). You can purchase matching batteries
385 from the Altus Metrum store, or other vendors, or you can
386 make your own. Pin 1 of the connector is positive, pin 2 is
387 negative. Spark Fun sells a cable with the connector
388 attached, which they call a <ulink
389 url="https://www.sparkfun.com/products/9914">JST Jumper 2
390 Wire Assembly</ulink>.
393 Many RC vendors also sell lithium polymer batteries with
394 this same connector. All that we have found use the opposite
395 polarity, and if you use them that way, you will damage or
396 destroy the flight computer.
400 <title>Hooking Up Pyro Charges</title>
402 Altus Metrum flight computers always have two screws for
403 each pyro charge. This means you shouldn't need to put two
404 wires into a screw terminal or connect leads from pyro
405 charges together externally.
408 On the flight computer, one lead from each charge is hooked
409 to the positive battery terminal through the power switch.
410 The other lead is connected through the pyro circuit, which
411 is connected to the negative battery terminal when the pyro
416 <title>Hooking Up a Power Switch</title>
418 Altus Metrum flight computers need an external power switch
419 to turn them on. This disconnects both the computer and the
420 pyro charges from the battery, preventing the charges from
421 firing when in the Off position. The switch is in-line with
422 the positive battery terminal.
425 <title>Using an External Active Switch Circuit</title>
427 You can use an active switch circuit, such as the
428 Featherweight Magnetic Switch, with any Altus Metrum
429 flight computer. These require three connections, one to
430 the battery, one to the positive power input on the flight
431 computer and one to ground. Find instructions on how to
432 hook these up for each flight computer below. The follow
433 the instructions that come with your active switch to
439 <title>Using a Separate Pyro Battery</title>
441 As mentioned above in the section on hooking up pyro
442 charges, one lead for each of the pyro charges is connected
443 through the power switch directly to the positive battery
444 terminal. The other lead is connected to the pyro circuit,
445 which connects it to the negative battery terminal when the
446 pyro circuit is fired. The pyro circuit on all of the flight
447 computers is designed to handle up to 16V.
450 To use a separate pyro battery, connect the negative pyro
451 battery terminal to the flight computer ground terminal,
452 the positive battery terminal to the igniter and the other
453 igniter lead to the negative pyro terminal on the flight
454 computer. When the pyro channel fires, it will complete the
455 circuit between the negative pyro terminal and the ground
456 terminal, firing the igniter. Specific instructions on how
457 to hook this up will be found in each section below.
461 <title>Using a Different Kind of Battery</title>
463 EasyMini and TeleMini v2 are designed to use either a
464 lithium polymer battery or any other battery producing
465 between 4 and 12 volts, such as a rectangular 9V
466 battery. TeleMega and TeleMetrum are not designed for this,
467 and must only be powered by a lithium polymer battery. Find
468 instructions on how to use other batteries in the EasyMini
469 and TeleMini sections below.
474 <title>Specifications</title>
476 Here's the full set of Altus Metrum products, both in
477 production and retired.
480 <title>Altus Metrum Electronics</title>
481 <?dbfo keep-together="always"?>
482 <tgroup cols='8' align='center' colsep='1' rowsep='1'>
483 <colspec align='center' colwidth='*' colname='Device'/>
484 <colspec align='center' colwidth='*' colname='Barometer'/>
485 <colspec align='center' colwidth='*' colname='Z-axis accelerometer'/>
486 <colspec align='center' colwidth='*' colname='GPS'/>
487 <colspec align='center' colwidth='*' colname='3D sensors'/>
488 <colspec align='center' colwidth='*' colname='Storage'/>
489 <colspec align='center' colwidth='*' colname='RF'/>
490 <colspec align='center' colwidth='*' colname='Battery'/>
493 <entry align='center'>Device</entry>
494 <entry align='center'>Barometer</entry>
495 <entry align='center'>Z-axis accelerometer</entry>
496 <entry align='center'>GPS</entry>
497 <entry align='center'>3D sensors</entry>
498 <entry align='center'>Storage</entry>
499 <entry align='center'>RF Output</entry>
500 <entry align='center'>Battery</entry>
505 <entry>TeleMetrum v1.0</entry>
506 <entry><para>MP3H6115 10km (33k')</para></entry>
507 <entry><para>MMA2202 50g</para></entry>
508 <entry>SkyTraq</entry>
515 <entry>TeleMetrum v1.1</entry>
516 <entry><para>MP3H6115 10km (33k')</para></entry>
517 <entry><para>MMA2202 50g</para></entry>
518 <entry>SkyTraq</entry>
525 <entry>TeleMetrum v1.2</entry>
526 <entry><para>MP3H6115 10km (33k')</para></entry>
527 <entry><para>ADXL78 70g</para></entry>
528 <entry>SkyTraq</entry>
535 <entry>TeleMetrum v2.0</entry>
536 <entry><para>MS5607 30km (100k')</para></entry>
537 <entry><para>MMA6555 102g</para></entry>
538 <entry>uBlox Max-7Q</entry>
545 <entry><para>TeleMini <?linebreak?>v1.0</para></entry>
546 <entry><para>MP3H6115 10km (33k')</para></entry>
555 <entry>TeleMini <?linebreak?>v2.0</entry>
556 <entry><para>MS5607 30km (100k')</para></entry>
562 <entry>3.7-12V</entry>
565 <entry>EasyMini <?linebreak?>v1.0</entry>
566 <entry><para>MS5607 30km (100k')</para></entry>
572 <entry>3.7-12V</entry>
575 <entry>TeleMega <?linebreak?>v1.0</entry>
576 <entry><para>MS5607 30km (100k')</para></entry>
577 <entry><para>MMA6555 102g</para></entry>
578 <entry>uBlox Max-7Q</entry>
579 <entry><para>MPU6000 HMC5883</para></entry>
588 <title>Altus Metrum Boards</title>
589 <?dbfo keep-together="always"?>
590 <tgroup cols='6' align='center' colsep='1' rowsep='1'>
591 <colspec align='center' colwidth='*' colname='Device'/>
592 <colspec align='center' colwidth='*' colname='Connectors'/>
593 <colspec align='center' colwidth='*' colname='Screw Terminals'/>
594 <colspec align='center' colwidth='*' colname='Width'/>
595 <colspec align='center' colwidth='*' colname='Length'/>
596 <colspec align='center' colwidth='*' colname='Tube Size'/>
599 <entry align='center'>Device</entry>
600 <entry align='center'>Connectors</entry>
601 <entry align='center'>Screw Terminals</entry>
602 <entry align='center'>Width</entry>
603 <entry align='center'>Length</entry>
604 <entry align='center'>Tube Size</entry>
609 <entry>TeleMetrum</entry>
613 Companion<?linebreak?>
617 <entry><para>Apogee pyro <?linebreak?>Main pyro <?linebreak?>Switch</para></entry>
618 <entry>1 inch (2.54cm)</entry>
619 <entry>2 ¾ inch (6.99cm)</entry>
620 <entry>29mm coupler</entry>
623 <entry><para>TeleMini <?linebreak?>v1.0</para></entry>
630 Apogee pyro <?linebreak?>
633 <entry>½ inch (1.27cm)</entry>
634 <entry>1½ inch (3.81cm)</entry>
635 <entry>18mm coupler</entry>
638 <entry>TeleMini <?linebreak?>v2.0</entry>
646 Apogee pyro <?linebreak?>
647 Main pyro <?linebreak?>
648 Battery <?linebreak?>
651 <entry>0.8 inch (2.03cm)</entry>
652 <entry>1½ inch (3.81cm)</entry>
653 <entry>24mm coupler</entry>
656 <entry>EasyMini</entry>
663 Apogee pyro <?linebreak?>
664 Main pyro <?linebreak?>
665 Battery <?linebreak?>
668 <entry>0.8 inch (2.03cm)</entry>
669 <entry>1½ inch (3.81cm)</entry>
670 <entry>24mm coupler</entry>
673 <entry>TeleMega</entry>
677 Companion<?linebreak?>
682 Apogee pyro <?linebreak?>
683 Main pyro<?linebreak?>
684 Pyro A-D<?linebreak?>
688 <entry>1¼ inch (3.18cm)</entry>
689 <entry>3¼ inch (8.26cm)</entry>
690 <entry>38mm coupler</entry>
697 <title>TeleMetrum</title>
701 <imagedata fileref="telemetrum-v1.1-thside.jpg" width="5.5in" scalefit="1"/>
706 TeleMetrum is a 1 inch by 2¾ inch circuit board. It was designed to
707 fit inside coupler for 29mm air-frame tubing, but using it in a tube that
708 small in diameter may require some creativity in mounting and wiring
709 to succeed! The presence of an accelerometer means TeleMetrum should
710 be aligned along the flight axis of the airframe, and by default the ¼
711 wave UHF wire antenna should be on the nose-cone end of the board. The
712 antenna wire is about 7 inches long, and wiring for a power switch and
713 the e-matches for apogee and main ejection charges depart from the
714 fin can end of the board, meaning an ideal “simple” avionics
715 bay for TeleMetrum should have at least 10 inches of interior length.
718 <title>TeleMetrum Screw Terminals</title>
720 TeleMetrum has six screw terminals on the end of the board
721 opposite the telemetry antenna. Two are for the power
722 switch, and two each for the apogee and main igniter
723 circuits. Using the picture above and starting from the top,
724 the terminals are as follows:
727 <title>TeleMetrum Screw Terminals</title>
728 <?dbfo keep-together="always"?>
729 <tgroup cols='3' align='center' colsep='1' rowsep='1'>
730 <colspec align='center' colwidth='*' colname='Pin #'/>
731 <colspec align='center' colwidth='2*' colname='Pin Name'/>
732 <colspec align='left' colwidth='5*' colname='Description'/>
735 <entry align='center'>Terminal #</entry>
736 <entry align='center'>Terminal Name</entry>
737 <entry align='center'>Description</entry>
743 <entry>Switch Output</entry>
744 <entry>Switch connection to flight computer</entry>
748 <entry>Switch Input</entry>
749 <entry>Switch connection to positive battery terminal</entry>
753 <entry>Main +</entry>
754 <entry>Main pyro channel common connection to battery +</entry>
758 <entry>Main -</entry>
759 <entry>Main pyro channel connection to pyro circuit</entry>
763 <entry>Apogee +</entry>
764 <entry>Apogee pyro channel common connection to battery +</entry>
768 <entry>Apogee -</entry>
769 <entry>Apogee pyro channel connection to pyro circuit</entry>
776 <title>Using a Separate Pyro Battery with TeleMetrum</title>
778 As described above, using an external pyro battery involves
779 connecting the negative battery terminal to the flight
780 computer ground, connecting the positive battery terminal to
781 one of the igniter leads and connecting the other igniter
782 lead to the per-channel pyro circuit connection.
785 To connect the negative battery terminal to the TeleMetrum
786 ground, insert a small piece of wire, 24 to 28 gauge
787 stranded, into the GND hole just above the screw terminal
788 strip and solder it in place.
791 Connecting the positive battery terminal to the pyro
792 charges must be done separate from TeleMetrum, by soldering
793 them together or using some other connector.
796 The other lead from each pyro charge is then inserted into
797 the appropriate per-pyro channel screw terminal (terminal 4 for the
798 Main charge, terminal 6 for the Apogee charge).
802 <title>Using an Active Switch with TeleMetrum</title>
804 As explained above, an external active switch requires three
805 connections, one to the positive battery terminal, one to
806 the flight computer positive input and one to ground.
809 The positive battery terminal is available on screw terminal
810 2, the positive flight computer input is on terminal 1. To
811 hook a lead to ground, solder a piece of wire, 24 to 28
812 gauge stranded, to the GND hole just above terminal 1.
817 <title>TeleMini v1.0</title>
821 <imagedata fileref="telemini-v1-top.jpg" width="5.5in" scalefit="1"/>
826 TeleMini v1.0 is ½ inches by 1½ inches. It was
827 designed to fit inside an 18mm air-frame tube, but using it in
828 a tube that small in diameter may require some creativity in
829 mounting and wiring to succeed! Since there is no
830 accelerometer, TeleMini can be mounted in any convenient
831 orientation. The default ¼ wave UHF wire antenna attached to
832 the center of one end of the board is about 7 inches long. Two
833 wires for the power switch are connected to holes in the
834 middle of the board. Screw terminals for the e-matches for
835 apogee and main ejection charges depart from the other end of
836 the board, meaning an ideal “simple” avionics bay for TeleMini
837 should have at least 9 inches of interior length.
840 <title>TeleMini v1.0 Screw Terminals</title>
842 TeleMini v1.0 has four screw terminals on the end of the
843 board opposite the telemetry antenna. Two are for the apogee
844 and two are for main igniter circuits. There are also wires
845 soldered to the board for the power switch. Using the
846 picture above and starting from the top for the terminals
847 and from the left for the power switch wires, the
848 connections are as follows:
851 <title>TeleMini v1.0 Connections</title>
852 <?dbfo keep-together="always"?>
853 <tgroup cols='3' align='center' colsep='1' rowsep='1'>
854 <colspec align='center' colwidth='*' colname='Pin #'/>
855 <colspec align='center' colwidth='2*' colname='Pin Name'/>
856 <colspec align='left' colwidth='5*' colname='Description'/>
859 <entry align='center'>Terminal #</entry>
860 <entry align='center'>Terminal Name</entry>
861 <entry align='center'>Description</entry>
867 <entry>Apogee -</entry>
868 <entry>Apogee pyro channel connection to pyro circuit</entry>
872 <entry>Apogee +</entry>
873 <entry>Apogee pyro channel common connection to battery +</entry>
877 <entry>Main -</entry>
878 <entry>Main pyro channel connection to pyro circuit</entry>
882 <entry>Main +</entry>
883 <entry>Main pyro channel common connection to battery +</entry>
887 <entry>Switch Output</entry>
888 <entry>Switch connection to flight computer</entry>
892 <entry>Switch Input</entry>
893 <entry>Switch connection to positive battery terminal</entry>
900 <title>Using a Separate Pyro Battery with TeleMini v1.0</title>
902 As described above, using an external pyro battery involves
903 connecting the negative battery terminal to the flight
904 computer ground, connecting the positive battery terminal to
905 one of the igniter leads and connecting the other igniter
906 lead to the per-channel pyro circuit connection. Because
907 there is no solid ground connection to use on TeleMini, this
911 The only available ground connection on TeleMini v1.0 are
912 the two mounting holes next to the telemetry
913 antenna. Somehow connect a small piece of wire to one of
914 those holes and hook it to the negative pyro battery terminal.
917 Connecting the positive battery terminal to the pyro
918 charges must be done separate from TeleMini v1.0, by soldering
919 them together or using some other connector.
922 The other lead from each pyro charge is then inserted into
923 the appropriate per-pyro channel screw terminal (terminal 3 for the
924 Main charge, terminal 1 for the Apogee charge).
928 <title>Using an Active Switch with TeleMini v1.0</title>
930 As explained above, an external active switch requires three
931 connections, one to the positive battery terminal, one to
932 the flight computer positive input and one to ground. Again,
933 because TeleMini doesn't have any good ground connection,
934 this is not recommended.
937 The positive battery terminal is available on the Right
938 power switch wire, the positive flight computer input is on
939 the left power switch wire. Hook a lead to either of the
940 mounting holes for a ground connection.
945 <title>TeleMini v2.0</title>
949 <imagedata fileref="telemini-v2-top.jpg" width="5.5in" scalefit="1"/>
954 TeleMini v2.0 is 0.8 inches by 1½ inches. It adds more
955 on-board data logging memory, a built-in USB connector and
956 screw terminals for the battery and power switch. The larger
957 board fits in a 24mm coupler. There's also a battery connector
958 for a LiPo battery if you want to use one of those.
961 <title>TeleMini v2.0 Screw Terminals</title>
963 TeleMini v2.0 has two sets of four screw terminals on the end of the
964 board opposite the telemetry antenna. Using the picture
965 above, the top four have connections for the main pyro
966 circuit and an external battery and the bottom four have
967 connections for the apogee pyro circuit and the power
968 switch. Counting from the left, the connections are as follows:
971 <title>TeleMini v2.0 Connections</title>
972 <?dbfo keep-together="always"?>
973 <tgroup cols='3' align='center' colsep='1' rowsep='1'>
974 <colspec align='center' colwidth='*' colname='Pin #'/>
975 <colspec align='center' colwidth='2*' colname='Pin Name'/>
976 <colspec align='left' colwidth='5*' colname='Description'/>
979 <entry align='center'>Terminal #</entry>
980 <entry align='center'>Terminal Name</entry>
981 <entry align='center'>Description</entry>
987 <entry>Main -</entry>
988 <entry>Main pyro channel connection to pyro circuit</entry>
992 <entry>Main +</entry>
993 <entry>Main pyro channel common connection to battery +</entry>
997 <entry>Battery +</entry>
998 <entry>Positive external battery terminal</entry>
1001 <entry>Top 4</entry>
1002 <entry>Battery -</entry>
1003 <entry>Negative external battery terminal</entry>
1006 <entry>Bottom 1</entry>
1007 <entry>Apogee -</entry>
1008 <entry>Apogee pyro channel connection to pyro circuit</entry>
1011 <entry>Bottom 2</entry>
1012 <entry>Apogee +</entry>
1013 <entry>Apogee pyro channel common connection to
1017 <entry>Bottom 3</entry>
1018 <entry>Switch Output</entry>
1019 <entry>Switch connection to flight computer</entry>
1022 <entry>Bottom 4</entry>
1023 <entry>Switch Input</entry>
1024 <entry>Switch connection to positive battery terminal</entry>
1031 <title>Using a Separate Pyro Battery with TeleMini v2.0</title>
1033 As described above, using an external pyro battery involves
1034 connecting the negative battery terminal to the flight
1035 computer ground, connecting the positive battery terminal to
1036 one of the igniter leads and connecting the other igniter
1037 lead to the per-channel pyro circuit connection.
1040 To connect the negative pyro battery terminal to TeleMini
1041 ground, connect it to the negative external battery
1042 connection, top terminal 4.
1045 Connecting the positive battery terminal to the pyro
1046 charges must be done separate from TeleMini v2.0, by soldering
1047 them together or using some other connector.
1050 The other lead from each pyro charge is then inserted into
1051 the appropriate per-pyro channel screw terminal (top
1052 terminal 1 for the Main charge, bottom terminal 1 for the
1057 <title>Using an Active Switch with TeleMini v2.0</title>
1059 As explained above, an external active switch requires three
1060 connections, one to the positive battery terminal, one to
1061 the flight computer positive input and one to ground. Use
1062 the negative external battery connection, top terminal 4 for
1066 The positive battery terminal is available on bottom
1067 terminal 4, the positive flight computer input is on the
1073 <title>EasyMini</title>
1077 <imagedata fileref="easymini-top.jpg" width="5.5in" scalefit="1"/>
1082 EasyMini is built on a 0.8 inch by 1½ inch circuit board. It's
1083 designed to fit in a 24mm coupler tube. The connectors and
1084 screw terminals match TeleMini v2.0, so you can easily swap between
1085 EasyMini and TeleMini.
1088 <title>EasyMini Screw Terminals</title>
1090 EasyMini has two sets of four screw terminals on the end of the
1091 board opposite the telemetry antenna. Using the picture
1092 above, the top four have connections for the main pyro
1093 circuit and an external battery and the bottom four have
1094 connections for the apogee pyro circuit and the power
1095 switch. Counting from the left, the connections are as follows:
1098 <title>EasyMini Connections</title>
1099 <?dbfo keep-together="always"?>
1100 <tgroup cols='3' align='center' colsep='1' rowsep='1'>
1101 <colspec align='center' colwidth='*' colname='Pin #'/>
1102 <colspec align='center' colwidth='2*' colname='Pin Name'/>
1103 <colspec align='left' colwidth='5*' colname='Description'/>
1106 <entry align='center'>Terminal #</entry>
1107 <entry align='center'>Terminal Name</entry>
1108 <entry align='center'>Description</entry>
1113 <entry>Top 1</entry>
1114 <entry>Main -</entry>
1115 <entry>Main pyro channel connection to pyro circuit</entry>
1118 <entry>Top 2</entry>
1119 <entry>Main +</entry>
1120 <entry>Main pyro channel common connection to battery +</entry>
1123 <entry>Top 3</entry>
1124 <entry>Battery +</entry>
1125 <entry>Positive external battery terminal</entry>
1128 <entry>Top 4</entry>
1129 <entry>Battery -</entry>
1130 <entry>Negative external battery terminal</entry>
1133 <entry>Bottom 1</entry>
1134 <entry>Apogee -</entry>
1135 <entry>Apogee pyro channel connection to pyro circuit</entry>
1138 <entry>Bottom 2</entry>
1139 <entry>Apogee +</entry>
1140 <entry>Apogee pyro channel common connection to
1144 <entry>Bottom 3</entry>
1145 <entry>Switch Output</entry>
1146 <entry>Switch connection to flight computer</entry>
1149 <entry>Bottom 4</entry>
1150 <entry>Switch Input</entry>
1151 <entry>Switch connection to positive battery terminal</entry>
1158 <title>Using a Separate Pyro Battery with EasyMini</title>
1160 As described above, using an external pyro battery involves
1161 connecting the negative battery terminal to the flight
1162 computer ground, connecting the positive battery terminal to
1163 one of the igniter leads and connecting the other igniter
1164 lead to the per-channel pyro circuit connection.
1167 To connect the negative pyro battery terminal to TeleMini
1168 ground, connect it to the negative external battery
1169 connection, top terminal 4.
1172 Connecting the positive battery terminal to the pyro
1173 charges must be done separate from EasyMini, by soldering
1174 them together or using some other connector.
1177 The other lead from each pyro charge is then inserted into
1178 the appropriate per-pyro channel screw terminal (top
1179 terminal 1 for the Main charge, bottom terminal 1 for the
1184 <title>Using an Active Switch with EasyMini</title>
1186 As explained above, an external active switch requires three
1187 connections, one to the positive battery terminal, one to
1188 the flight computer positive input and one to ground. Use
1189 the negative external battery connection, top terminal 4 for
1193 The positive battery terminal is available on bottom
1194 terminal 4, the positive flight computer input is on the
1200 <title>TeleMega</title>
1204 <imagedata fileref="telemega-v1.0-top.jpg" width="5.5in" scalefit="1"/>
1209 TeleMega is a 1¼ inch by 3¼ inch circuit board. It was
1210 designed to easily fit in a 38mm coupler. Like TeleMetrum,
1211 TeleMega has an accelerometer and so it must be mounted so that
1212 the board is aligned with the flight axis. It can be mounted
1213 either antenna up or down.
1216 <title>TeleMega Screw Terminals</title>
1218 TeleMega has two sets of nine screw terminals on the end of
1219 the board opposite the telemetry antenna. They are as follows:
1222 <title>TeleMega Screw Terminals</title>
1223 <?dbfo keep-together="always"?>
1224 <tgroup cols='3' align='center' colsep='1' rowsep='1'>
1225 <colspec align='center' colwidth='*' colname='Pin #'/>
1226 <colspec align='center' colwidth='2*' colname='Pin Name'/>
1227 <colspec align='left' colwidth='5*' colname='Description'/>
1230 <entry align='center'>Terminal #</entry>
1231 <entry align='center'>Terminal Name</entry>
1232 <entry align='center'>Description</entry>
1237 <entry>Top 1</entry>
1238 <entry>Switch Input</entry>
1239 <entry>Switch connection to positive battery terminal</entry>
1242 <entry>Top 2</entry>
1243 <entry>Switch Output</entry>
1244 <entry>Switch connection to flight computer</entry>
1247 <entry>Top 3</entry>
1249 <entry>Ground connection for use with external active switch</entry>
1252 <entry>Top 4</entry>
1253 <entry>Main -</entry>
1254 <entry>Main pyro channel connection to pyro circuit</entry>
1257 <entry>Top 5</entry>
1258 <entry>Main +</entry>
1259 <entry>Main pyro channel common connection to battery +</entry>
1262 <entry>Top 6</entry>
1263 <entry>Apogee -</entry>
1264 <entry>Apogee pyro channel connection to pyro circuit</entry>
1267 <entry>Top 7</entry>
1268 <entry>Apogee +</entry>
1269 <entry>Apogee pyro channel common connection to battery +</entry>
1272 <entry>Top 8</entry>
1274 <entry>D pyro channel connection to pyro circuit</entry>
1277 <entry>Top 9</entry>
1279 <entry>D pyro channel common connection to battery +</entry>
1282 <entry>Bottom 1</entry>
1284 <entry>Ground connection for negative pyro battery terminal</entry>
1287 <entry>Bottom 2</entry>
1289 <entry>Positive pyro battery terminal</entry>
1292 <entry>Bottom 3</entry>
1295 Power switch output. Use to connect main battery to
1300 <entry>Bottom 4</entry>
1302 <entry>A pyro channel connection to pyro circuit</entry>
1305 <entry>Bottom 5</entry>
1307 <entry>A pyro channel common connection to battery +</entry>
1310 <entry>Bottom 6</entry>
1312 <entry>B pyro channel connection to pyro circuit</entry>
1315 <entry>Bottom 7</entry>
1317 <entry>B pyro channel common connection to battery +</entry>
1320 <entry>Bottom 8</entry>
1322 <entry>C pyro channel connection to pyro circuit</entry>
1325 <entry>Bottom 9</entry>
1327 <entry>C pyro channel common connection to battery +</entry>
1334 <title>Using a Separate Pyro Battery with TeleMega</title>
1336 TeleMega provides explicit support for an external pyro
1337 battery. All that is required is to remove the jumper
1338 between the lipo terminal (Bottom 3) and the pyro terminal
1339 (Bottom 2). Then hook the negative pyro battery terminal to ground
1340 (Bottom 1) and the positive pyro battery to the pyro battery
1341 input (Bottom 2). You can then use the existing pyro screw
1342 terminals to hook up all of the pyro charges.
1346 <title>Using Only One Battery With TeleMega</title>
1348 Because TeleMega has built-in support for a separate pyro
1349 battery, if you want to fly with just one battery running
1350 both the computer and firing the charges, you need to
1351 connect the flight computer battery to the pyro
1352 circuit. TeleMega has two screw terminals for this—hook a
1353 wire from the Lipo terminal (Bottom 3) to the Pyro terminal
1358 <title>Using an Active Switch with TeleMega</title>
1360 As explained above, an external active switch requires three
1361 connections, one to the positive battery terminal, one to
1362 the flight computer positive input and one to ground.
1365 The positive battery terminal is available on Top terminal
1366 1, the positive flight computer input is on Top terminal
1367 2. Ground is on Top terminal 3.
1372 <title>Flight Data Recording</title>
1374 Each flight computer logs data at 100 samples per second
1375 during ascent and 10 samples per second during descent, except
1376 for TeleMini v1.0, which records ascent at 10 samples per
1377 second and descent at 1 sample per second. Data are logged to
1378 an on-board flash memory part, which can be partitioned into
1379 several equal-sized blocks, one for each flight.
1382 <title>Data Storage on Altus Metrum altimeters</title>
1383 <?dbfo keep-together="always"?>
1384 <tgroup cols='4' align='center' colsep='1' rowsep='1'>
1385 <colspec align='center' colwidth='*' colname='Device'/>
1386 <colspec align='center' colwidth='*' colname='Bytes per sample'/>
1387 <colspec align='center' colwidth='*' colname='Total storage'/>
1388 <colspec align='center' colwidth='*' colname='Minutes of
1392 <entry align='center'>Device</entry>
1393 <entry align='center'>Bytes per Sample</entry>
1394 <entry align='center'>Total Storage</entry>
1395 <entry align='center'>Minutes at Full Rate</entry>
1400 <entry>TeleMetrum v1.0</entry>
1406 <entry>TeleMetrum v1.1 v1.2</entry>
1412 <entry>TeleMetrum v2.0</entry>
1418 <entry>TeleMini v1.0</entry>
1424 <entry>TeleMini v2.0</entry>
1430 <entry>EasyMini</entry>
1436 <entry>TeleMega</entry>
1445 The on-board flash is partitioned into separate flight logs,
1446 each of a fixed maximum size. Increase the maximum size of
1447 each log and you reduce the number of flights that can be
1448 stored. Decrease the size and you can store more flights.
1451 Configuration data is also stored in the flash memory on
1452 TeleMetrum v1.x, TeleMini and EasyMini. This consumes 64kB
1453 of flash space. This configuration space is not available
1454 for storing flight log data. TeleMetrum v2.0 and TeleMega
1455 store configuration data in a bit of eeprom available within
1456 the processor chip, leaving that space available in flash for
1460 To compute the amount of space needed for a single flight, you
1461 can multiply the expected ascent time (in seconds) by 100
1462 times bytes-per-sample, multiply the expected descent time (in
1463 seconds) by 10 times the bytes per sample and add the two
1464 together. That will slightly under-estimate the storage (in
1465 bytes) needed for the flight. For instance, a TeleMetrum v2.0 flight spending
1466 20 seconds in ascent and 150 seconds in descent will take
1467 about (20 * 1600) + (150 * 160) = 56000 bytes of storage. You
1468 could store dozens of these flights in the on-board flash.
1471 The default size allows for several flights on each flight
1472 computer, except for TeleMini v1.0, which only holds data for a
1473 single flight. You can adjust the size.
1476 Altus Metrum flight computers will not overwrite existing
1477 flight data, so be sure to download flight data and erase it
1478 from the flight computer before it fills up. The flight
1479 computer will still successfully control the flight even if it
1480 cannot log data, so the only thing you will lose is the data.
1484 <title>Installation</title>
1486 A typical installation involves attaching
1487 only a suitable battery, a single pole switch for
1488 power on/off, and two pairs of wires connecting e-matches for the
1489 apogee and main ejection charges. All Altus Metrum products are
1490 designed for use with single-cell batteries with 3.7 volts
1491 nominal. TeleMini v2.0 and EasyMini may also be used with other
1492 batteries as long as they supply between 4 and 12 volts.
1495 The battery connectors are a standard 2-pin JST connector and
1496 match batteries sold by Spark Fun. These batteries are
1497 single-cell Lithium Polymer batteries that nominally provide 3.7
1498 volts. Other vendors sell similar batteries for RC aircraft
1499 using mating connectors, however the polarity for those is
1500 generally reversed from the batteries used by Altus Metrum
1501 products. In particular, the Tenergy batteries supplied for use
1502 in Featherweight flight computers are not compatible with Altus
1503 Metrum flight computers or battery chargers. <emphasis>Check
1504 polarity and voltage before connecting any battery not purchased
1505 from Altus Metrum or Spark Fun.</emphasis>
1508 By default, we use the unregulated output of the battery directly
1509 to fire ejection charges. This works marvelously with standard
1510 low-current e-matches like the J-Tek from MJG Technologies, and with
1511 Quest Q2G2 igniters. However, if you want or need to use a separate
1512 pyro battery, check out the “External Pyro Battery” section in this
1513 manual for instructions on how to wire that up. The altimeters are
1514 designed to work with an external pyro battery of no more than 15 volts.
1517 Ejection charges are wired directly to the screw terminal block
1518 at the aft end of the altimeter. You'll need a very small straight
1519 blade screwdriver for these screws, such as you might find in a
1520 jeweler's screwdriver set.
1523 Except for TeleMini v1.0, the flight computers also use the
1524 screw terminal block for the power switch leads. On TeleMini v1.0,
1525 the power switch leads are soldered directly to the board and
1526 can be connected directly to a switch.
1529 For most air-frames, the integrated antennas are more than
1530 adequate. However, if you are installing in a carbon-fiber or
1531 metal electronics bay which is opaque to RF signals, you may need to
1532 use off-board external antennas instead. In this case, you can
1533 replace the stock UHF antenna wire with an edge-launched SMA connector,
1534 and, on TeleMetrum v1, you can unplug the integrated GPS
1535 antenna and select an appropriate off-board GPS antenna with
1536 cable terminating in a U.FL connector.
1541 <title>System Operation</title>
1543 <title>Firmware Modes </title>
1545 The AltOS firmware build for the altimeters has two
1546 fundamental modes, “idle” and “flight”. Which of these modes
1547 the firmware operates in is determined at start up time. For
1548 TeleMetrum and TeleMega, which have accelerometers, the mode is
1549 controlled by the orientation of the
1550 rocket (well, actually the board, of course...) at the time
1551 power is switched on. If the rocket is “nose up”, then
1552 the flight computer assumes it's on a rail or rod being prepared for
1553 launch, so the firmware chooses flight mode. However, if the
1554 rocket is more or less horizontal, the firmware instead enters
1555 idle mode. Since TeleMini v2.0 and EasyMini don't have an
1556 accelerometer we can use to determine orientation, “idle” mode
1557 is selected if the board is connected via USB to a computer,
1558 otherwise the board enters “flight” mode. TeleMini v1.0
1559 selects “idle” mode if it receives a command packet within the
1560 first five seconds of operation.
1563 At power on, the altimeter will beep out the battery voltage
1564 to the nearest tenth of a volt. Each digit is represented by
1565 a sequence of short “dit” beeps, with a pause between
1566 digits. A zero digit is represented with one long “dah”
1567 beep. Then there will be a short pause while the altimeter
1568 completes initialization and self test, and decides which mode
1572 Here's a short summary of all of the modes and the beeping (or
1573 flashing, in the case of TeleMini v1) that accompanies each
1574 mode. In the description of the beeping pattern, “dit” means a
1575 short beep while "dah" means a long beep (three times as
1576 long). “Brap” means a long dissonant tone.
1578 <title>AltOS Modes</title>
1579 <?dbfo keep-together="always"?>
1580 <tgroup cols='4' align='center' colsep='1' rowsep='1'>
1581 <colspec align='center' colwidth='*' colname='Mode Name'/>
1582 <colspec align='center' colwidth='*' colname='Letter'/>
1583 <colspec align='center' colwidth='*' colname='Beeps'/>
1584 <colspec align='center' colwidth='*' colname='Description'/>
1587 <entry>Mode Name</entry>
1588 <entry>Abbreviation</entry>
1589 <entry>Beeps</entry>
1590 <entry>Description</entry>
1595 <entry>Startup</entry>
1597 <entry>battery voltage in decivolts</entry>
1600 Calibrating sensors, detecting orientation.
1607 <entry>dit dit</entry>
1610 Ready to accept commands over USB or radio link.
1617 <entry>dit dah dah dit</entry>
1620 Waiting for launch. Not listening for commands.
1625 <entry>Boost</entry>
1627 <entry>dah dit dit dit</entry>
1630 Accelerating upwards.
1637 <entry>dit dit dah dit</entry>
1640 Decelerating, but moving faster than 200m/s.
1645 <entry>Coast</entry>
1647 <entry>dah dit dah dit</entry>
1650 Decelerating, moving slower than 200m/s
1655 <entry>Drogue</entry>
1657 <entry>dah dit dit</entry>
1660 Descending after apogee. Above main height.
1667 <entry>dah dah</entry>
1670 Descending. Below main height.
1675 <entry>Landed</entry>
1677 <entry>dit dah dit dit</entry>
1680 Stable altitude for at least ten seconds.
1685 <entry>Sensor error</entry>
1687 <entry>dah dit dit dah</entry>
1690 Error detected during sensor calibration.
1699 In flight or “pad” mode, the altimeter engages the flight
1700 state machine, goes into transmit-only mode to send telemetry,
1701 and waits for launch to be detected. Flight mode is indicated
1702 by an “di-dah-dah-dit” (“P” for pad) on the beeper or lights,
1703 followed by beeps or flashes indicating the state of the
1704 pyrotechnic igniter continuity. One beep/flash indicates
1705 apogee continuity, two beeps/flashes indicate main continuity,
1706 three beeps/flashes indicate both apogee and main continuity,
1707 and one longer “brap” sound which is made by rapidly
1708 alternating between two tones indicates no continuity. For a
1709 dual deploy flight, make sure you're getting three beeps or
1710 flashes before launching! For apogee-only or motor eject
1711 flights, do what makes sense.
1714 If idle mode is entered, you will hear an audible “di-dit” or
1715 see two short flashes (“I” for idle), and the flight state
1716 machine is disengaged, thus no ejection charges will fire.
1717 The altimeters also listen for the radio link when in idle
1718 mode for requests sent via TeleDongle. Commands can be issued
1719 in idle mode over either USB or the radio link
1720 equivalently. TeleMini v1.0 only has the radio link. Idle
1721 mode is useful for configuring the altimeter, for extracting
1722 data from the on-board storage chip after flight, and for
1723 ground testing pyro charges.
1726 In “Idle” and “Pad” modes, once the mode indication
1727 beeps/flashes and continuity indication has been sent, if
1728 there is no space available to log the flight in on-board
1729 memory, the flight computer will emit a warbling tone (much
1730 slower than the “no continuity tone”)
1733 Here's a summary of all of the “pad” and “idle” mode indications.
1735 <title>Pad/Idle Indications</title>
1736 <?dbfo keep-together="always"?>
1737 <tgroup cols='3' align='center' colsep='1' rowsep='1'>
1738 <colspec align='center' colwidth='*' colname='Name'/>
1739 <colspec align='center' colwidth='*' colname='Beeps'/>
1740 <colspec align='center' colwidth='*' colname='Description'/>
1744 <entry>Beeps</entry>
1745 <entry>Description</entry>
1750 <entry>Neither</entry>
1754 No continuity detected on either apogee or main
1760 <entry>Apogee</entry>
1764 Continuity detected only on apogee igniter.
1770 <entry>dit dit</entry>
1773 Continuity detected only on main igniter.
1779 <entry>dit dit dit</entry>
1782 Continuity detected on both igniters.
1787 <entry>Storage Full</entry>
1788 <entry>warble</entry>
1791 On-board data logging storage is full. This will
1792 not prevent the flight computer from safely
1793 controlling the flight or transmitting telemetry
1794 signals, but no record of the flight will be
1795 stored in on-board flash.
1804 Once landed, the flight computer will signal that by emitting
1805 the “Landed” sound described above, after which it will beep
1806 out the apogee height (in meters). Each digit is represented
1807 by a sequence of short “dit” beeps, with a pause between
1808 digits. A zero digit is represented with one long “dah”
1809 beep. The flight computer will continue to report landed mode
1810 and beep out the maximum height until turned off.
1813 One “neat trick” of particular value when TeleMetrum or TeleMega are used with
1814 very large air-frames, is that you can power the board up while the
1815 rocket is horizontal, such that it comes up in idle mode. Then you can
1816 raise the air-frame to launch position, and issue a 'reset' command
1817 via TeleDongle over the radio link to cause the altimeter to reboot and
1818 come up in flight mode. This is much safer than standing on the top
1819 step of a rickety step-ladder or hanging off the side of a launch
1820 tower with a screw-driver trying to turn on your avionics before
1821 installing igniters!
1824 TeleMini v1.0 is configured solely via the radio link. Of course, that
1825 means you need to know the TeleMini radio configuration values
1826 or you won't be able to communicate with it. For situations
1827 when you don't have the radio configuration values, TeleMini v1.0
1828 offers an 'emergency recovery' mode. In this mode, TeleMini is
1829 configured as follows:
1833 Sets the radio frequency to 434.550MHz
1838 Sets the radio calibration back to the factory value.
1843 Sets the callsign to N0CALL
1848 Does not go to 'pad' mode after five seconds.
1854 To get into 'emergency recovery' mode, first find the row of
1855 four small holes opposite the switch wiring. Using a short
1856 piece of small gauge wire, connect the outer two holes
1857 together, then power TeleMini up. Once the red LED is lit,
1858 disconnect the wire and the board should signal that it's in
1859 'idle' mode after the initial five second startup period.
1865 TeleMetrum and TeleMega include a complete GPS receiver. A
1866 complete explanation of how GPS works is beyond the scope of
1867 this manual, but the bottom line is that the GPS receiver
1868 needs to lock onto at least four satellites to obtain a solid
1869 3 dimensional position fix and know what time it is.
1872 The flight computers provide backup power to the GPS chip any time a
1873 battery is connected. This allows the receiver to “warm start” on
1874 the launch rail much faster than if every power-on were a GPS
1875 “cold start”. In typical operations, powering up
1876 on the flight line in idle mode while performing final air-frame
1877 preparation will be sufficient to allow the GPS receiver to cold
1878 start and acquire lock. Then the board can be powered down during
1879 RSO review and installation on a launch rod or rail. When the board
1880 is turned back on, the GPS system should lock very quickly, typically
1881 long before igniter installation and return to the flight line are
1886 <title>Controlling An Altimeter Over The Radio Link</title>
1888 One of the unique features of the Altus Metrum system is the
1889 ability to create a two way command link between TeleDongle
1890 and an altimeter using the digital radio transceivers
1891 built into each device. This allows you to interact with the
1892 altimeter from afar, as if it were directly connected to the
1896 Any operation which can be performed with a flight computer can
1897 either be done with the device directly connected to the
1898 computer via the USB cable, or through the radio
1899 link. TeleMini v1.0 doesn't provide a USB connector and so it is
1900 always communicated with over radio. Select the appropriate
1901 TeleDongle device when the list of devices is presented and
1902 AltosUI will interact with an altimeter over the radio link.
1905 One oddity in the current interface is how AltosUI selects the
1906 frequency for radio communications. Instead of providing
1907 an interface to specifically configure the frequency, it uses
1908 whatever frequency was most recently selected for the target
1909 TeleDongle device in Monitor Flight mode. If you haven't ever
1910 used that mode with the TeleDongle in question, select the
1911 Monitor Flight button from the top level UI, and pick the
1912 appropriate TeleDongle device. Once the flight monitoring
1913 window is open, select the desired frequency and then close it
1914 down again. All radio communications will now use that frequency.
1919 Save Flight Data—Recover flight data from the rocket without
1925 Configure altimeter apogee delays, main deploy heights
1926 and additional pyro event conditions
1927 to respond to changing launch conditions. You can also
1928 'reboot' the altimeter. Use this to remotely enable the
1929 flight computer by turning TeleMetrum or TeleMega on in “idle” mode,
1930 then once the air-frame is oriented for launch, you can
1931 reboot the altimeter and have it restart in pad mode
1932 without having to climb the scary ladder.
1937 Fire Igniters—Test your deployment charges without snaking
1938 wires out through holes in the air-frame. Simply assemble the
1939 rocket as if for flight with the apogee and main charges
1940 loaded, then remotely command the altimeter to fire the
1946 Operation over the radio link for configuring an altimeter, ground
1947 testing igniters, and so forth uses the same RF frequencies as flight
1948 telemetry. To configure the desired TeleDongle frequency, select
1949 the monitor flight tab, then use the frequency selector and
1950 close the window before performing other desired radio operations.
1953 The flight computers only enable radio commanding in 'idle' mode.
1954 TeleMetrum and TeleMega use the accelerometer to detect which orientation they
1955 start up in, so make sure you have the flight computer lying horizontally when you turn
1956 it on. Otherwise, it will start in 'pad' mode ready for
1957 flight, and will not be listening for command packets from TeleDongle.
1960 TeleMini listens for a command packet for five seconds after
1961 first being turned on, if it doesn't hear anything, it enters
1962 'pad' mode, ready for flight and will no longer listen for
1963 command packets. The easiest way to connect to TeleMini is to
1964 initiate the command and select the TeleDongle device. At this
1965 point, the TeleDongle will be attempting to communicate with
1966 the TeleMini. Now turn TeleMini on, and it should immediately
1967 start communicating with the TeleDongle and the desired
1968 operation can be performed.
1971 You can monitor the operation of the radio link by watching the
1972 lights on the devices. The red LED will flash each time a packet
1973 is transmitted, while the green LED will light up on TeleDongle when
1974 it is waiting to receive a packet from the altimeter.
1978 <title>Ground Testing </title>
1980 An important aspect of preparing a rocket using electronic deployment
1981 for flight is ground testing the recovery system. Thanks
1982 to the bi-directional radio link central to the Altus Metrum system,
1983 this can be accomplished in a TeleMega, TeleMetrum or TeleMini equipped rocket
1984 with less work than you may be accustomed to with other systems. It
1988 Just prep the rocket for flight, then power up the altimeter
1989 in “idle” mode (placing air-frame horizontal for TeleMetrum or TeleMega, or
1990 selecting the Configure Altimeter tab for TeleMini). This will cause
1991 the firmware to go into “idle” mode, in which the normal flight
1992 state machine is disabled and charges will not fire without
1993 manual command. You can now command the altimeter to fire the apogee
1994 or main charges from a safe distance using your computer and
1995 TeleDongle and the Fire Igniter tab to complete ejection testing.
1999 <title>Radio Link </title>
2001 Our flight computers all incorporate an RF transceiver, but
2002 it's not a full duplex system... each end can only be transmitting or
2003 receiving at any given moment. So we had to decide how to manage the
2007 By design, the altimeter firmware listens for the radio link when
2008 it's in “idle mode”, which
2009 allows us to use the radio link to configure the rocket, do things like
2010 ejection tests, and extract data after a flight without having to
2011 crack open the air-frame. However, when the board is in “flight
2012 mode”, the altimeter only
2013 transmits and doesn't listen at all. That's because we want to put
2014 ultimate priority on event detection and getting telemetry out of
2016 the radio in case the rocket crashes and we aren't able to extract
2020 We don't generally use a 'normal packet radio' mode like APRS
2021 because they're just too inefficient. The GFSK modulation we
2022 use is FSK with the base-band pulses passed through a Gaussian
2023 filter before they go into the modulator to limit the
2024 transmitted bandwidth. When combined with forward error
2025 correction and interleaving, this allows us to have a very
2026 robust 19.2 kilobit data link with only 10-40 milliwatts of
2027 transmit power, a whip antenna in the rocket, and a hand-held
2028 Yagi on the ground. We've had flights to above 21k feet AGL
2029 with great reception, and calculations suggest we should be
2030 good to well over 40k feet AGL with a 5-element yagi on the
2031 ground with our 10mW units and over 100k feet AGL with the
2032 40mW devices. We hope to fly boards to higher altitudes over
2033 time, and would of course appreciate customer feedback on
2034 performance in higher altitude flights!
2040 TeleMetrum v2.0 and TeleMega can send APRS if desired, and the
2041 interval between APRS packets can be configured. As each APRS
2042 packet takes a full second to transmit, we recommend an
2043 interval of at least 5 seconds to avoid consuming too much
2044 battery power or radio channel bandwidth. You can configure
2045 the APRS interval using AltosUI; that process is described in
2046 the Configure Altimeter section of the AltosUI chapter.
2049 AltOS uses the APRS compressed position report data format,
2050 which provides for higher position precision and shorter
2051 packets than the original APRS format. It also includes
2052 altitude data, which is invaluable when tracking rockets. We
2053 haven't found a receiver which doesn't handle compressed
2054 positions, but it's just possible that you have one, so if you
2055 have an older device that can receive the raw packets but
2056 isn't displaying position information, it's possible that this
2060 The APRS packet format includes a comment field that can have
2061 arbitrary text in it. AltOS uses this to send status
2062 information about the flight computer. It sends four fields as
2063 shown in the following table.
2066 <title>Altus Metrum APRS Comments</title>
2067 <?dbfo keep-together="always"?>
2068 <tgroup cols='3' align='center' colsep='1' rowsep='1'>
2069 <colspec align='center' colwidth='*' colname='Field'/>
2070 <colspec align='center' colwidth='*' colname='Example'/>
2071 <colspec align='center' colwidth='4*' colname='Description'/>
2074 <entry align='center'>Field</entry>
2075 <entry align='center'>Example</entry>
2076 <entry align='center'>Description</entry>
2083 <entry>GPS Status U for unlocked, L for locked</entry>
2088 <entry>Number of Satellites in View</entry>
2093 <entry>Altimeter Battery Voltage</entry>
2098 <entry>Apogee Igniter Voltage</entry>
2103 <entry>Main Igniter Voltage</entry>
2109 Here's an example of an APRS comment showing GPS lock with 6
2110 satellites in view, a primary battery at 4.0V, and
2111 apogee and main igniters both at 3.7V.
2117 Make sure your primary battery is above 3.8V, any connected
2118 igniters are above 3.5V and GPS is locked with at least 5 or 6
2119 satellites in view before flying. If GPS is switching between
2120 L and U regularly, then it doesn't have a good lock and you
2121 should wait until it becomes stable.
2124 If the GPS receiver loses lock, the APRS data transmitted will
2125 contain the last position for which GPS lock was
2126 available. You can tell that this has happened by noticing
2127 that the GPS status character switches from 'L' to 'U'. Before
2128 GPS has locked, APRS will transmit zero for latitude,
2129 longitude and altitude.
2133 <title>Configurable Parameters</title>
2135 Configuring an Altus Metrum altimeter for flight is very
2136 simple. Even on our baro-only TeleMini and EasyMini boards,
2137 the use of a Kalman filter means there is no need to set a
2138 “mach delay”. The few configurable parameters can all be set
2139 using AltosUI over USB or or radio link via TeleDongle. Read
2140 the Configure Altimeter section in the AltosUI chapter below
2141 for more information.
2144 <title>Radio Frequency</title>
2146 Altus Metrum boards support radio frequencies in the 70cm
2147 band. By default, the configuration interface provides a
2148 list of 10 “standard” frequencies in 100kHz channels starting at
2149 434.550MHz. However, the firmware supports use of
2150 any 50kHz multiple within the 70cm band. At any given
2151 launch, we highly recommend coordinating when and by whom each
2152 frequency will be used to avoid interference. And of course, both
2153 altimeter and TeleDongle must be configured to the same
2154 frequency to successfully communicate with each other.
2158 <title>Callsign</title>
2160 This sets the callsign used for telemetry, APRS and the
2161 packet link. For telemetry and APRS, this is used to
2162 identify the device. For the packet link, the callsign must
2163 match that configured in AltosUI or the link will not
2164 work. This is to prevent accidental configuration of another
2165 Altus Metrum flight computer operating on the same frequency nearby.
2169 <title>Telemetry/RDF/APRS Enable</title>
2171 You can completely disable the radio while in flight, if
2172 necessary. This doesn't disable the packet link in idle
2177 <title>APRS Interval</title>
2179 This selects how often APRS packets are transmitted. Set
2180 this to zero to disable APRS without also disabling the
2181 regular telemetry and RDF transmissions. As APRS takes a
2182 full second to transmit a single position report, we
2183 recommend sending packets no more than once every 5 seconds.
2187 <title>Apogee Delay</title>
2189 Apogee delay is the number of seconds after the altimeter detects flight
2190 apogee that the drogue charge should be fired. In most cases, this
2191 should be left at the default of 0. However, if you are flying
2192 redundant electronics such as for an L3 certification, you may wish
2193 to set one of your altimeters to a positive delay so that both
2194 primary and backup pyrotechnic charges do not fire simultaneously.
2197 The Altus Metrum apogee detection algorithm fires exactly at
2198 apogee. If you are also flying an altimeter like the
2199 PerfectFlite MAWD, which only supports selecting 0 or 1
2200 seconds of apogee delay, you may wish to set the MAWD to 0
2201 seconds delay and set the TeleMetrum to fire your backup 2
2202 or 3 seconds later to avoid any chance of both charges
2203 firing simultaneously. We've flown several air-frames this
2204 way quite happily, including Keith's successful L3 cert.
2208 <title>Apogee Lockout</title>
2210 Apogee lockout is the number of seconds after boost where
2211 the flight computer will not fire the apogee charge, even if
2212 the rocket appears to be at apogee. This is often called
2213 'Mach Delay', as it is intended to prevent a flight computer
2214 from unintentionally firing apogee charges due to the pressure
2215 spike that occurrs across a mach transition. Altus Metrum
2216 flight computers include a Kalman filter which is not fooled
2217 by this sharp pressure increase, and so this setting should
2218 be left at the default value of zero to disable it.
2222 <title>Main Deployment Altitude</title>
2224 By default, the altimeter will fire the main deployment charge at an
2225 elevation of 250 meters (about 820 feet) above ground. We think this
2226 is a good elevation for most air-frames, but feel free to change this
2227 to suit. In particular, if you are flying two altimeters, you may
2229 deployment elevation for the backup altimeter to be something lower
2230 than the primary so that both pyrotechnic charges don't fire
2235 <title>Maximum Flight Log</title>
2237 Changing this value will set the maximum amount of flight
2238 log storage that an individual flight will use. The
2239 available storage is divided into as many flights of the
2240 specified size as can fit in the available space. You can
2241 download and erase individual flight logs. If you fill up
2242 the available storage, future flights will not get logged
2243 until you erase some of the stored ones.
2246 Even though our flight computers (except TeleMini v1.0) can store
2247 multiple flights, we strongly recommend downloading and saving
2248 flight data after each flight.
2252 <title>Ignite Mode</title>
2254 Instead of firing one charge at apogee and another charge at
2255 a fixed height above the ground, you can configure the
2256 altimeter to fire both at apogee or both during
2257 descent. This was added to support an airframe Bdale designed that
2258 had two altimeters, one in the fin can and one in the nose.
2261 Providing the ability to use both igniters for apogee or
2262 main allows some level of redundancy without needing two
2263 flight computers. In Redundant Apogee or Redundant Main
2264 mode, the two charges will be fired two seconds apart.
2268 <title>Pad Orientation</title>
2270 TeleMetrum and TeleMega measure acceleration along the axis
2271 of the board. Which way the board is oriented affects the
2272 sign of the acceleration value. Instead of trying to guess
2273 which way the board is mounted in the air frame, the
2274 altimeter must be explicitly configured for either Antenna
2275 Up or Antenna Down. The default, Antenna Up, expects the end
2276 of the board connected to the 70cm antenna to be nearest the
2277 nose of the rocket, with the end containing the screw
2278 terminals nearest the tail.
2282 <title>Configurable Pyro Channels</title>
2284 In addition to the usual Apogee and Main pyro channels,
2285 TeleMega has four additional channels that can be configured
2286 to activate when various flight conditions are
2287 satisfied. You can select as many conditions as necessary;
2288 all of them must be met in order to activate the
2289 channel. The conditions available are:
2294 Acceleration away from the ground. Select a value, and
2295 then choose whether acceleration should be above or
2296 below that value. Acceleration is positive upwards, so
2297 accelerating towards the ground would produce negative
2298 numbers. Acceleration during descent is noisy and
2299 inaccurate, so be careful when using it during these
2300 phases of the flight.
2305 Vertical speed. Select a value, and then choose whether
2306 vertical speed should be above or below that
2307 value. Speed is positive upwards, so moving towards the
2308 ground would produce negative numbers. Speed during
2309 descent is a bit noisy and so be careful when using it
2310 during these phases of the flight.
2315 Height. Select a value, and then choose whether the
2316 height above the launch pad should be above or below
2322 Orientation. TeleMega contains a 3-axis gyroscope and
2323 accelerometer which is used to measure the current
2324 angle. Note that this angle is not the change in angle
2325 from the launch pad, but rather absolute relative to
2326 gravity; the 3-axis accelerometer is used to compute the
2327 angle of the rocket on the launch pad and initialize the
2328 system. Because this value is computed by integrating
2329 rate gyros, it gets progressively less accurate as the
2330 flight goes on. It should have an accumulated error of
2331 less than 0.2°/second (after 10 seconds of flight, the
2332 error should be less than 2°).
2335 The usual use of the orientation configuration is to
2336 ensure that the rocket is traveling mostly upwards when
2337 deciding whether to ignite air starts or additional
2338 stages. For that, choose a reasonable maximum angle
2339 (like 20°) and set the motor igniter to require an angle
2340 of less than that value.
2345 Flight Time. Time since boost was detected. Select a
2346 value and choose whether to activate the pyro channel
2347 before or after that amount of time.
2352 Ascending. A simple test saying whether the rocket is
2353 going up or not. This is exactly equivalent to testing
2354 whether the speed is > 0.
2359 Descending. A simple test saying whether the rocket is
2360 going down or not. This is exactly equivalent to testing
2361 whether the speed is < 0.
2366 After Motor. The flight software counts each time the
2367 rocket starts accelerating (presumably due to a motor or
2368 motors igniting). Use this value to count ignitions for
2369 multi-staged or multi-airstart launches.
2374 Delay. This value doesn't perform any checks, instead it
2375 inserts a delay between the time when the other
2376 parameters become true and when the pyro channel is
2382 Flight State. The flight software tracks the flight
2383 through a sequence of states:
2387 Boost. The motor has lit and the rocket is
2388 accelerating upwards.
2393 Fast. The motor has burned out and the rocket is
2394 decelerating, but it is going faster than 200m/s.
2399 Coast. The rocket is still moving upwards and
2400 decelerating, but the speed is less than 200m/s.
2405 Drogue. The rocket has reached apogee and is heading
2406 back down, but is above the configured Main
2412 Main. The rocket is still descending, and is below
2418 Landed. The rocket is no longer moving.
2424 You can select a state to limit when the pyro channel
2425 may activate; note that the check is based on when the
2426 rocket transitions <emphasis>into</emphasis> the state, and so checking for
2427 “greater than Boost” means that the rocket is currently
2428 in boost or some later state.
2431 When a motor burns out, the rocket enters either Fast or
2432 Coast state (depending on how fast it is moving). If the
2433 computer detects upwards acceleration again, it will
2434 move back to Boost state.
2443 <title>AltosUI</title>
2447 <imagedata fileref="altosui.png" width="4.6in"/>
2452 The AltosUI program provides a graphical user interface for
2453 interacting with the Altus Metrum product family. AltosUI can
2454 monitor telemetry data, configure devices and many other
2455 tasks. The primary interface window provides a selection of
2456 buttons, one for each major activity in the system. This chapter
2457 is split into sections, each of which documents one of the tasks
2458 provided from the top-level toolbar.
2461 <title>Monitor Flight</title>
2462 <subtitle>Receive, Record and Display Telemetry Data</subtitle>
2464 Selecting this item brings up a dialog box listing all of the
2465 connected TeleDongle devices. When you choose one of these,
2466 AltosUI will create a window to display telemetry data as
2467 received by the selected TeleDongle device.
2472 <imagedata fileref="device-selection.png" width="3.1in"/>
2477 All telemetry data received are automatically recorded in
2478 suitable log files. The name of the files includes the current
2479 date and rocket serial and flight numbers.
2482 The radio frequency being monitored by the TeleDongle device is
2483 displayed at the top of the window. You can configure the
2484 frequency by clicking on the frequency box and selecting the desired
2485 frequency. AltosUI remembers the last frequency selected for each
2486 TeleDongle and selects that automatically the next time you use
2490 Below the TeleDongle frequency selector, the window contains a few
2491 significant pieces of information about the altimeter providing
2492 the telemetry data stream:
2496 <para>The configured call-sign</para>
2499 <para>The device serial number</para>
2502 <para>The flight number. Each altimeter remembers how many
2508 The rocket flight state. Each flight passes through several
2509 states including Pad, Boost, Fast, Coast, Drogue, Main and
2515 The Received Signal Strength Indicator value. This lets
2516 you know how strong a signal TeleDongle is receiving. The
2517 radio inside TeleDongle operates down to about -99dBm;
2518 weaker signals may not be receivable. The packet link uses
2519 error detection and correction techniques which prevent
2520 incorrect data from being reported.
2525 The age of the displayed data, in seconds since the last
2526 successfully received telemetry packet. In normal operation
2527 this will stay in the low single digits. If the number starts
2528 counting up, then you are no longer receiving data over the radio
2529 link from the flight computer.
2534 Finally, the largest portion of the window contains a set of
2535 tabs, each of which contain some information about the rocket.
2536 They're arranged in 'flight order' so that as the flight
2537 progresses, the selected tab automatically switches to display
2538 data relevant to the current state of the flight. You can select
2539 other tabs at any time. The final 'table' tab displays all of
2540 the raw telemetry values in one place in a spreadsheet-like format.
2543 <title>Launch Pad</title>
2547 <imagedata fileref="launch-pad.png" width="5.5in"/>
2552 The 'Launch Pad' tab shows information used to decide when the
2553 rocket is ready for flight. The first elements include red/green
2554 indicators, if any of these is red, you'll want to evaluate
2555 whether the rocket is ready to launch:
2558 <term>Battery Voltage</term>
2561 This indicates whether the Li-Po battery powering the
2562 flight computer has sufficient charge to last for
2563 the duration of the flight. A value of more than
2564 3.8V is required for a 'GO' status.
2569 <term>Apogee Igniter Voltage</term>
2572 This indicates whether the apogee
2573 igniter has continuity. If the igniter has a low
2574 resistance, then the voltage measured here will be close
2575 to the Li-Po battery voltage. A value greater than 3.2V is
2576 required for a 'GO' status.
2581 <term>Main Igniter Voltage</term>
2584 This indicates whether the main
2585 igniter has continuity. If the igniter has a low
2586 resistance, then the voltage measured here will be close
2587 to the Li-Po battery voltage. A value greater than 3.2V is
2588 required for a 'GO' status.
2593 <term>On-board Data Logging</term>
2596 This indicates whether there is
2597 space remaining on-board to store flight data for the
2598 upcoming flight. If you've downloaded data, but failed
2599 to erase flights, there may not be any space
2600 left. Most of our flight computers can store multiple
2601 flights, depending on the configured maximum flight log
2602 size. TeleMini v1.0 stores only a single flight, so it
2604 downloaded and erased after each flight to capture
2605 data. This only affects on-board flight logging; the
2606 altimeter will still transmit telemetry and fire
2607 ejection charges at the proper times even if the flight
2608 data storage is full.
2613 <term>GPS Locked</term>
2616 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
2617 currently able to compute position information. GPS requires
2618 at least 4 satellites to compute an accurate position.
2623 <term>GPS Ready</term>
2626 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
2627 10 consecutive positions without losing lock. This ensures
2628 that the GPS receiver has reliable reception from the
2636 The Launchpad tab also shows the computed launch pad position
2637 and altitude, averaging many reported positions to improve the
2638 accuracy of the fix.
2642 <title>Ascent</title>
2646 <imagedata fileref="ascent.png" width="5.5in"/>
2651 This tab is shown during Boost, Fast and Coast
2652 phases. The information displayed here helps monitor the
2653 rocket as it heads towards apogee.
2656 The height, speed, acceleration and tilt are shown along
2657 with the maximum values for each of them. This allows you to
2658 quickly answer the most commonly asked questions you'll hear
2662 The current latitude and longitude reported by the GPS are
2663 also shown. Note that under high acceleration, these values
2664 may not get updated as the GPS receiver loses position
2665 fix. Once the rocket starts coasting, the receiver should
2666 start reporting position again.
2669 Finally, the current igniter voltages are reported as in the
2670 Launch Pad tab. This can help diagnose deployment failures
2671 caused by wiring which comes loose under high acceleration.
2675 <title>Descent</title>
2679 <imagedata fileref="descent.png" width="5.5in"/>
2684 Once the rocket has reached apogee and (we hope) activated the
2685 apogee charge, attention switches to tracking the rocket on
2686 the way back to the ground, and for dual-deploy flights,
2687 waiting for the main charge to fire.
2690 To monitor whether the apogee charge operated correctly, the
2691 current descent rate is reported along with the current
2692 height. Good descent rates vary based on the choice of recovery
2693 components, but generally range from 15-30m/s on drogue and should
2694 be below 10m/s when under the main parachute in a dual-deploy flight.
2697 With GPS-equipped flight computers, you can locate the rocket in the
2698 sky using the elevation and bearing information to figure
2699 out where to look. Elevation is in degrees above the
2700 horizon. Bearing is reported in degrees relative to true
2701 north. Range can help figure out how big the rocket will
2702 appear. Ground Distance shows how far it is to a point
2703 directly under the rocket and can help figure out where the
2704 rocket is likely to land. Note that all of these values are
2705 relative to the pad location. If the elevation is near 90°,
2706 the rocket is over the pad, not over you.
2709 Finally, the igniter voltages are reported in this tab as
2710 well, both to monitor the main charge as well as to see what
2711 the status of the apogee charge is. Note that some commercial
2712 e-matches are designed to retain continuity even after being
2713 fired, and will continue to show as green or return from red to
2718 <title>Landed</title>
2722 <imagedata fileref="landed.png" width="5.5in"/>
2727 Once the rocket is on the ground, attention switches to
2728 recovery. While the radio signal is often lost once the
2729 rocket is on the ground, the last reported GPS position is
2730 generally within a short distance of the actual landing location.
2733 The last reported GPS position is reported both by
2734 latitude and longitude as well as a bearing and distance from
2735 the launch pad. The distance should give you a good idea of
2736 whether to walk or hitch a ride. Take the reported
2737 latitude and longitude and enter them into your hand-held GPS
2738 unit and have that compute a track to the landing location.
2741 Our flight computers will continue to transmit RDF
2742 tones after landing, allowing you to locate the rocket by
2743 following the radio signal if necessary. You may need to get
2744 away from the clutter of the flight line, or even get up on
2745 a hill (or your neighbor's RV roof) to receive the RDF signal.
2748 The maximum height, speed and acceleration reported
2749 during the flight are displayed for your admiring observers.
2750 The accuracy of these immediate values depends on the quality
2751 of your radio link and how many packets were received.
2752 Recovering the on-board data after flight may yield
2753 more precise results.
2756 To get more detailed information about the flight, you can
2757 click on the 'Graph Flight' button which will bring up a
2758 graph window for the current flight.
2762 <title>Table</title>
2766 <imagedata fileref="table.png" width="5.5in"/>
2771 The table view shows all of the data available from the
2772 flight computer. Probably the most useful data on
2773 this tab is the detailed GPS information, which includes
2774 horizontal dilution of precision information, and
2775 information about the signal being received from the satellites.
2779 <title>Site Map</title>
2783 <imagedata fileref="site-map.png" width="5.5in"/>
2788 When the TeleMetrum has a GPS fix, the Site Map tab will map
2789 the rocket's position to make it easier for you to locate the
2790 rocket, both while it is in the air, and when it has landed. The
2791 rocket's state is indicated by color: white for pad, red for
2792 boost, pink for fast, yellow for coast, light blue for drogue,
2793 dark blue for main, and black for landed.
2796 The map's default scale is approximately 3m (10ft) per pixel. The map
2797 can be dragged using the left mouse button. The map will attempt
2798 to keep the rocket roughly centered while data is being received.
2801 You can adjust the style of map and the zoom level with
2802 buttons on the right side of the map window. You can draw a
2803 line on the map by moving the mouse over the map with a
2804 button other than the left one pressed, or by pressing the
2805 left button while also holding down the shift key. The
2806 length of the line in real-world units will be shown at the
2810 Images are fetched automatically via the Google Maps Static API,
2811 and cached on disk for reuse. If map images cannot be downloaded,
2812 the rocket's path will be traced on a dark gray background
2816 You can pre-load images for your favorite launch sites
2817 before you leave home; check out the 'Preload Maps' section below.
2821 <title>Ignitor</title>
2825 <imagedata fileref="ignitor.png" width="5.5in"/>
2830 TeleMega includes four additional programmable pyro
2831 channels. The Ignitor tab shows whether each of them has
2832 continuity. If an ignitor has a low resistance, then the
2833 voltage measured here will be close to the pyro battery
2834 voltage. A value greater than 3.2V is required for a 'GO'
2840 <title>Save Flight Data</title>
2842 The altimeter records flight data to its internal flash memory.
2843 TeleMetrum data is recorded at a much higher rate than the telemetry
2844 system can handle, and is not subject to radio drop-outs. As
2845 such, it provides a more complete and precise record of the
2846 flight. The 'Save Flight Data' button allows you to read the
2847 flash memory and write it to disk.
2850 Clicking on the 'Save Flight Data' button brings up a list of
2851 connected flight computers and TeleDongle devices. If you select a
2852 flight computer, the flight data will be downloaded from that
2853 device directly. If you select a TeleDongle device, flight data
2854 will be downloaded from a flight computer over radio link via the
2855 specified TeleDongle. See the chapter on Controlling An Altimeter
2856 Over The Radio Link for more information.
2859 After the device has been selected, a dialog showing the
2860 flight data saved in the device will be shown allowing you to
2861 select which flights to download and which to delete. With
2862 version 0.9 or newer firmware, you must erase flights in order
2863 for the space they consume to be reused by another
2864 flight. This prevents accidentally losing flight data
2865 if you neglect to download data before flying again. Note that
2866 if there is no more space available in the device, then no
2867 data will be recorded during the next flight.
2870 The file name for each flight log is computed automatically
2871 from the recorded flight date, altimeter serial number and
2872 flight number information.
2876 <title>Replay Flight</title>
2878 Select this button and you are prompted to select a flight
2879 record file, either a .telem file recording telemetry data or a
2880 .eeprom file containing flight data saved from the altimeter
2884 Once a flight record is selected, the flight monitor interface
2885 is displayed and the flight is re-enacted in real time. Check
2886 the Monitor Flight chapter above to learn how this window operates.
2890 <title>Graph Data</title>
2892 Select this button and you are prompted to select a flight
2893 record file, either a .telem file recording telemetry data or a
2894 .eeprom file containing flight data saved from
2898 Note that telemetry files will generally produce poor graphs
2899 due to the lower sampling rate and missed telemetry packets.
2900 Use saved flight data in .eeprom files for graphing where possible.
2903 Once a flight record is selected, a window with multiple tabs is
2907 <title>Flight Graph</title>
2911 <imagedata fileref="graph.png" width="6in" scalefit="1"/>
2916 By default, the graph contains acceleration (blue),
2917 velocity (green) and altitude (red).
2920 The graph can be zoomed into a particular area by clicking and
2921 dragging down and to the right. Once zoomed, the graph can be
2922 reset by clicking and dragging up and to the left. Holding down
2923 control and clicking and dragging allows the graph to be panned.
2924 The right mouse button causes a pop-up menu to be displayed, giving
2925 you the option save or print the plot.
2929 <title>Configure Graph</title>
2933 <imagedata fileref="graph-configure.png" width="6in" scalefit="1"/>
2938 This selects which graph elements to show, and, at the
2939 very bottom, lets you switch between metric and
2944 <title>Flight Statistics</title>
2948 <imagedata fileref="graph-stats.png" width="6in" scalefit="1"/>
2953 Shows overall data computed from the flight.
2961 <imagedata fileref="graph-map.png" width="6in" scalefit="1"/>
2966 Shows a satellite image of the flight area overlaid
2967 with the path of the flight. The red concentric
2968 circles mark the launch pad, the black concentric
2969 circles mark the landing location.
2974 <title>Export Data</title>
2976 This tool takes the raw data files and makes them available for
2977 external analysis. When you select this button, you are prompted to
2978 select a flight data file, which can be either a .eeprom or .telem.
2979 The .eeprom files contain higher resolution and more continuous data,
2980 while .telem files contain receiver signal strength information.
2981 Next, a second dialog appears which is used to select
2982 where to write the resulting file. It has a selector to choose
2983 between CSV and KML file formats.
2986 <title>Comma Separated Value Format</title>
2988 This is a text file containing the data in a form suitable for
2989 import into a spreadsheet or other external data analysis
2990 tool. The first few lines of the file contain the version and
2991 configuration information from the altimeter, then
2992 there is a single header line which labels all of the
2993 fields. All of these lines start with a '#' character which
2994 many tools can be configured to skip over.
2997 The remaining lines of the file contain the data, with each
2998 field separated by a comma and at least one space. All of
2999 the sensor values are converted to standard units, with the
3000 barometric data reported in both pressure, altitude and
3001 height above pad units.
3005 <title>Keyhole Markup Language (for Google Earth)</title>
3007 This is the format used by Google Earth to provide an overlay
3008 within that application. With this, you can use Google Earth to
3009 see the whole flight path in 3D.
3014 <title>Configure Altimeter</title>
3018 <imagedata fileref="configure-altimeter.png" width="3.6in" scalefit="1"/>
3023 Select this button and then select either an altimeter or
3024 TeleDongle Device from the list provided. Selecting a TeleDongle
3025 device will use the radio link to configure a remote altimeter.
3028 The first few lines of the dialog provide information about the
3029 connected device, including the product name,
3030 software version and hardware serial number. Below that are the
3031 individual configuration entries.
3034 At the bottom of the dialog, there are four buttons:
3041 This writes any changes to the
3042 configuration parameter block in flash memory. If you don't
3043 press this button, any changes you make will be lost.
3051 This resets the dialog to the most recently saved values,
3052 erasing any changes you have made.
3060 This reboots the device. Use this to
3061 switch from idle to pad mode by rebooting once the rocket is
3062 oriented for flight, or to confirm changes you think you saved
3071 This closes the dialog. Any unsaved changes will be
3078 The rest of the dialog contains the parameters to be configured.
3081 <title>Main Deploy Altitude</title>
3083 This sets the altitude (above the recorded pad altitude) at
3084 which the 'main' igniter will fire. The drop-down menu shows
3085 some common values, but you can edit the text directly and
3086 choose whatever you like. If the apogee charge fires below
3087 this altitude, then the main charge will fire two seconds
3088 after the apogee charge fires.
3092 <title>Apogee Delay</title>
3094 When flying redundant electronics, it's often important to
3095 ensure that multiple apogee charges don't fire at precisely
3096 the same time, as that can over pressurize the apogee deployment
3097 bay and cause a structural failure of the air-frame. The Apogee
3098 Delay parameter tells the flight computer to fire the apogee
3099 charge a certain number of seconds after apogee has been
3104 <title>Apogee Lockoug</title>
3106 Apogee lockout is the number of seconds after boost where
3107 the flight computer will not fire the apogee charge, even if
3108 the rocket appears to be at apogee. This is often called
3109 'Mach Delay', as it is intended to prevent a flight computer
3110 from unintentionally firing apogee charges due to the pressure
3111 spike that occurrs across a mach transition. Altus Metrum
3112 flight computers include a Kalman filter which is not fooled
3113 by this sharp pressure increase, and so this setting should
3114 be left at the default value of zero to disable it.
3118 <title>Frequency</title>
3120 This configures which of the frequencies to use for both
3121 telemetry and packet command mode. Note that if you set this
3122 value via packet command mode, the TeleDongle frequency will
3123 also be automatically reconfigured to match so that
3124 communication will continue afterwards.
3128 <title>RF Calibration</title>
3130 The radios in every Altus Metrum device are calibrated at the
3131 factory to ensure that they transmit and receive on the
3132 specified frequency. If you need to you can adjust the calibration
3133 by changing this value. Do not do this without understanding what
3134 the value means, read the appendix on calibration and/or the source
3135 code for more information. To change a TeleDongle's calibration,
3136 you must reprogram the unit completely.
3140 <title>Telemetry/RDF/APRS Enable</title>
3142 Enables the radio for transmission during flight. When
3143 disabled, the radio will not transmit anything during flight
3148 <title>APRS Interval</title>
3150 How often to transmit GPS information via APRS (in
3151 seconds). When set to zero, APRS transmission is
3152 disabled. This option is available on TeleMetrum v2 and
3153 TeleMega boards. TeleMetrum v1 boards cannot transmit APRS
3154 packets. Note that a single APRS packet takes nearly a full
3155 second to transmit, so enabling this option will prevent
3156 sending any other telemetry during that time.
3160 <title>Callsign</title>
3162 This sets the call sign included in each telemetry packet. Set this
3163 as needed to conform to your local radio regulations.
3167 <title>Maximum Flight Log Size</title>
3169 This sets the space (in kilobytes) allocated for each flight
3170 log. The available space will be divided into chunks of this
3171 size. A smaller value will allow more flights to be stored,
3172 a larger value will record data from longer flights.
3176 <title>Ignitor Firing Mode</title>
3178 This configuration parameter allows the two standard ignitor
3179 channels (Apogee and Main) to be used in different
3184 <term>Dual Deploy</term>
3187 This is the usual mode of operation; the
3188 'apogee' channel is fired at apogee and the 'main'
3189 channel at the height above ground specified by the
3190 'Main Deploy Altitude' during descent.
3195 <term>Redundant Apogee</term>
3198 This fires both channels at
3199 apogee, the 'apogee' channel first followed after a two second
3200 delay by the 'main' channel.
3205 <term>Redundant Main</term>
3208 This fires both channels at the
3209 height above ground specified by the Main Deploy
3210 Altitude setting during descent. The 'apogee'
3211 channel is fired first, followed after a two second
3212 delay by the 'main' channel.
3219 <title>Pad Orientation</title>
3221 Because they include accelerometers, TeleMetrum and
3222 TeleMega are sensitive to the orientation of the board. By
3223 default, they expect the antenna end to point forward. This
3224 parameter allows that default to be changed, permitting the
3225 board to be mounted with the antenna pointing aft instead.
3229 <term>Antenna Up</term>
3232 In this mode, the antenna end of the
3233 flight computer must point forward, in line with the
3234 expected flight path.
3239 <term>Antenna Down</term>
3242 In this mode, the antenna end of the
3243 flight computer must point aft, in line with the
3244 expected flight path.
3251 <title>Beeper Frequency</title>
3253 The beeper on all Altus Metrum flight computers works best
3254 at 4000Hz, however if you have more than one flight computer
3255 in a single airframe, having all of them sound at the same
3256 frequency can be confusing. This parameter lets you adjust
3257 the base beeper frequency value.
3261 <title>Configure Pyro Channels</title>
3265 <imagedata fileref="configure-pyro.png" width="6in" scalefit="1"/>
3270 This opens a separate window to configure the additional
3271 pyro channels available on TeleMega. One column is
3272 presented for each channel. Each row represents a single
3273 parameter, if enabled the parameter must meet the specified
3274 test for the pyro channel to be fired. See the Pyro Channels
3275 section in the System Operation chapter above for a
3276 description of these parameters.
3279 Select conditions and set the related value; the pyro
3280 channel will be activated when <emphasis>all</emphasis> of the
3281 conditions are met. Each pyro channel has a separate set of
3282 configuration values, so you can use different values for
3283 the same condition with different channels.
3286 At the bottom of the window, the 'Pyro Firing Time'
3287 configuration sets the length of time (in seconds) which
3288 each of these pyro channels will fire for.
3291 Once you have selected the appropriate configuration for all
3292 of the necessary pyro channels, you can save the pyro
3293 configuration along with the rest of the flight computer
3294 configuration by pressing the 'Save' button in the main
3295 Configure Flight Computer window.
3300 <title>Configure AltosUI</title>
3304 <imagedata fileref="configure-altosui.png" width="2.4in" scalefit="1"/>
3309 This button presents a dialog so that you can configure the AltosUI global settings.
3312 <title>Voice Settings</title>
3314 AltosUI provides voice announcements during flight so that you
3315 can keep your eyes on the sky and still get information about
3316 the current flight status. However, sometimes you don't want
3323 <para>Turns all voice announcements on and off</para>
3327 <term>Test Voice</term>
3330 Plays a short message allowing you to verify
3331 that the audio system is working and the volume settings
3339 <title>Log Directory</title>
3341 AltosUI logs all telemetry data and saves all TeleMetrum flash
3342 data to this directory. This directory is also used as the
3343 staring point when selecting data files for display or export.
3346 Click on the directory name to bring up a directory choosing
3347 dialog, select a new directory and click 'Select Directory' to
3348 change where AltosUI reads and writes data files.
3352 <title>Callsign</title>
3354 This value is transmitted in each command packet sent from
3355 TeleDongle and received from an altimeter. It is not used in
3356 telemetry mode, as the callsign configured in the altimeter board
3357 is included in all telemetry packets. Configure this
3358 with the AltosUI operators call sign as needed to comply with
3359 your local radio regulations.
3362 Note that to successfully command a flight computer over the radio
3363 (to configure the altimeter, monitor idle, or fire pyro charges),
3364 the callsign configured here must exactly match the callsign
3365 configured in the flight computer. This matching is case
3370 <title>Imperial Units</title>
3372 This switches between metric units (meters) and imperial
3373 units (feet and miles). This affects the display of values
3374 use during flight monitoring, configuration, data graphing
3375 and all of the voice announcements. It does not change the
3376 units used when exporting to CSV files, those are always
3377 produced in metric units.
3381 <title>Font Size</title>
3383 Selects the set of fonts used in the flight monitor
3384 window. Choose between the small, medium and large sets.
3388 <title>Serial Debug</title>
3390 This causes all communication with a connected device to be
3391 dumped to the console from which AltosUI was started. If
3392 you've started it from an icon or menu entry, the output
3393 will simply be discarded. This mode can be useful to debug
3394 various serial communication issues.
3398 <title>Manage Frequencies</title>
3400 This brings up a dialog where you can configure the set of
3401 frequencies shown in the various frequency menus. You can
3402 add as many as you like, or even reconfigure the default
3403 set. Changing this list does not affect the frequency
3404 settings of any devices, it only changes the set of
3405 frequencies shown in the menus.
3410 <title>Configure Groundstation</title>
3414 <imagedata fileref="configure-groundstation.png" width="3.1in" scalefit="1"/>
3419 Select this button and then select a TeleDongle Device from the list provided.
3422 The first few lines of the dialog provide information about the
3423 connected device, including the product name,
3424 software version and hardware serial number. Below that are the
3425 individual configuration entries.
3428 Note that the TeleDongle itself doesn't save any configuration
3429 data, the settings here are recorded on the local machine in
3430 the Java preferences database. Moving the TeleDongle to
3431 another machine, or using a different user account on the same
3432 machine will cause settings made here to have no effect.
3435 At the bottom of the dialog, there are three buttons:
3442 This writes any changes to the
3443 local Java preferences file. If you don't
3444 press this button, any changes you make will be lost.
3452 This resets the dialog to the most recently saved values,
3453 erasing any changes you have made.
3461 This closes the dialog. Any unsaved changes will be
3468 The rest of the dialog contains the parameters to be configured.
3471 <title>Frequency</title>
3473 This configures the frequency to use for both telemetry and
3474 packet command mode. Set this before starting any operation
3475 involving packet command mode so that it will use the right
3476 frequency. Telemetry monitoring mode also provides a menu to
3477 change the frequency, and that menu also sets the same Java
3478 preference value used here.
3482 <title>Radio Calibration</title>
3484 The radios in every Altus Metrum device are calibrated at the
3485 factory to ensure that they transmit and receive on the
3486 specified frequency. To change a TeleDongle's calibration,
3487 you must reprogram the unit completely, so this entry simply
3488 shows the current value and doesn't allow any changes.
3493 <title>Flash Image</title>
3495 This reprograms Altus Metrum devices with new
3496 firmware. TeleMetrum v1.x, TeleDongle, TeleMini and TeleBT are
3497 all reprogrammed by using another similar unit as a
3498 programming dongle (pair programming). TeleMega, TeleMetrum v2
3499 and EasyMini are all programmed directly over their USB ports
3500 (self programming). Please read the directions for flashing
3501 devices in the Updating Device Firmware chapter below.
3505 <title>Fire Igniter</title>
3509 <imagedata fileref="fire-igniter.png" width="1.2in" scalefit="1"/>
3514 This activates the igniter circuits in the flight computer to help
3515 test recovery systems deployment. Because this command can operate
3516 over the Packet Command Link, you can prepare the rocket as
3517 for flight and then test the recovery system without needing
3518 to snake wires inside the air-frame.
3521 Selecting the 'Fire Igniter' button brings up the usual device
3522 selection dialog. Pick the desired device. This brings up another
3523 window which shows the current continuity test status for all
3524 of the pyro channels.
3527 Next, select the desired igniter to fire. This will enable the
3531 Select the 'Arm' button. This enables the 'Fire' button. The
3532 word 'Arm' is replaced by a countdown timer indicating that
3533 you have 10 seconds to press the 'Fire' button or the system
3534 will deactivate, at which point you start over again at
3535 selecting the desired igniter.
3539 <title>Scan Channels</title>
3543 <imagedata fileref="scan-channels.png" width="3.2in" scalefit="1"/>
3548 This listens for telemetry packets on all of the configured
3549 frequencies, displaying information about each device it
3550 receives a packet from. You can select which of the three
3551 telemetry formats should be tried; by default, it only listens
3552 for the standard telemetry packets used in v1.0 and later
3557 <title>Load Maps</title>
3561 <imagedata fileref="load-maps.png" width="5.2in" scalefit="1"/>
3566 Before heading out to a new launch site, you can use this to
3567 load satellite images in case you don't have internet
3568 connectivity at the site. This loads a fairly large area
3569 around the launch site, which should cover any flight you're likely to make.
3572 There's a drop-down menu of launch sites we know about; if
3573 your favorites aren't there, please let us know the lat/lon
3574 and name of the site. The contents of this list are actually
3575 downloaded from our server at run-time, so as new sites are sent
3576 in, they'll get automatically added to this list.
3577 If the launch site isn't in the list, you can manually enter the lat/lon values
3580 There are four different kinds of maps you can view; you can
3581 select which to download by selecting as many as you like from
3582 the available types:
3588 A combination of satellite imagery and road data. This
3589 is the default view.
3594 <term>Satellite</term>
3597 Just the satellite imagery without any annotation.
3602 <term>Roadmap</term>
3605 Roads, political boundaries and a few geographic features.
3610 <term>Terrain</term>
3613 Contour intervals and shading that show hills and
3621 You can specify the range of zoom levels to download; smaller
3622 numbers show more area with less resolution. The default
3623 level, 0, shows about 3m/pixel. One zoom level change
3624 doubles or halves that number.
3627 The Tile Radius value sets how large an area around the center
3628 point to download. Each tile is 512x512 pixels, and the
3629 'radius' value specifies how many tiles away from the center
3630 will be downloaded. Specify a radius of 0 and you get only the
3631 center tile. A radius of 1 loads a 3x3 grid, centered on the
3635 Clicking the 'Load Map' button will fetch images from Google
3636 Maps; note that Google limits how many images you can fetch at
3637 once, so if you load more than one launch site, you may get
3638 some gray areas in the map which indicate that Google is tired
3639 of sending data to you. Try again later.
3643 <title>Monitor Idle</title>
3645 This brings up a dialog similar to the Monitor Flight UI,
3646 except it works with the altimeter in “idle” mode by sending
3647 query commands to discover the current state rather than
3648 listening for telemetry packets. Because this uses command
3649 mode, it needs to have the TeleDongle and flight computer
3650 callsigns match exactly. If you can receive telemetry, but
3651 cannot manage to run Monitor Idle, then it's very likely that
3652 your callsigns are different in some way.
3657 <title>AltosDroid</title>
3659 AltosDroid provides the same flight monitoring capabilities as
3660 AltosUI, but runs on Android devices and is designed to connect
3661 to a TeleBT receiver over Bluetooth™. AltosDroid monitors
3662 telemetry data, logging it to internal storage in the Android
3663 device, and presents that data in a UI the same way the 'Monitor
3664 Flight' window does in AltosUI.
3667 This manual will explain how to configure AltosDroid, connect
3668 to TeleBT, operate the flight monitoring interface and describe
3669 what the displayed data means.
3672 <title>Installing AltosDroid</title>
3674 AltosDroid is available from the Google Play store. To install
3675 it on your Android device, open the Google Play Store
3676 application and search for “altosdroid”. Make sure you don't
3677 have a space between “altos” and “droid” or you probably won't
3678 find what you want. That should bring you to the right page
3679 from which you can download and install the application.
3683 <title>Connecting to TeleBT</title>
3685 Press the Android 'Menu' button or soft-key to see the
3686 configuration options available. Select the 'Connect a device'
3687 option and then the 'Scan for devices' entry at the bottom to
3688 look for your TeleBT device. Select your device, and when it
3689 asks for the code, enter '1234'.
3692 Subsequent connections will not require you to enter that
3693 code, and your 'paired' device will appear in the list without
3698 <title>Configuring AltosDroid</title>
3700 The only configuration option available for AltosDroid is
3701 which frequency to listen on. Press the Android 'Menu' button
3702 or soft-key and pick the 'Select radio frequency' entry. That
3703 brings up a menu of pre-set radio frequencies; pick the one
3704 which matches your altimeter.
3708 <title>AltosDroid Flight Monitoring</title>
3710 AltosDroid is designed to mimic the AltosUI flight monitoring
3711 display, providing separate tabs for each stage of your rocket
3712 flight along with a tab containing a map of the local area
3713 with icons marking the current location of the altimeter and
3719 The 'Launch Pad' tab shows information used to decide when the
3720 rocket is ready for flight. The first elements include red/green
3721 indicators, if any of these is red, you'll want to evaluate
3722 whether the rocket is ready to launch:
3725 <term>Battery Voltage</term>
3728 This indicates whether the Li-Po battery
3729 powering the TeleMetrum has sufficient charge to last for
3730 the duration of the flight. A value of more than
3731 3.8V is required for a 'GO' status.
3736 <term>Apogee Igniter Voltage</term>
3739 This indicates whether the apogee
3740 igniter has continuity. If the igniter has a low
3741 resistance, then the voltage measured here will be close
3742 to the Li-Po battery voltage. A value greater than 3.2V is
3743 required for a 'GO' status.
3748 <term>Main Igniter Voltage</term>
3751 This indicates whether the main
3752 igniter has continuity. If the igniter has a low
3753 resistance, then the voltage measured here will be close
3754 to the Li-Po battery voltage. A value greater than 3.2V is
3755 required for a 'GO' status.
3760 <term>On-board Data Logging</term>
3763 This indicates whether there is
3764 space remaining on-board to store flight data for the
3765 upcoming flight. If you've downloaded data, but failed
3766 to erase flights, there may not be any space
3767 left. TeleMetrum can store multiple flights, depending
3768 on the configured maximum flight log size. TeleMini
3769 stores only a single flight, so it will need to be
3770 downloaded and erased after each flight to capture
3771 data. This only affects on-board flight logging; the
3772 altimeter will still transmit telemetry and fire
3773 ejection charges at the proper times.
3778 <term>GPS Locked</term>
3781 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
3782 currently able to compute position information. GPS requires
3783 at least 4 satellites to compute an accurate position.
3788 <term>GPS Ready</term>
3791 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
3792 10 consecutive positions without losing lock. This ensures
3793 that the GPS receiver has reliable reception from the
3801 The Launchpad tab also shows the computed launch pad position
3802 and altitude, averaging many reported positions to improve the
3803 accuracy of the fix.
3808 <title>Downloading Flight Logs</title>
3810 AltosDroid always saves every bit of telemetry data it
3811 receives. To download that to a computer for use with AltosUI,
3812 simply remove the SD card from your Android device, or connect
3813 your device to your computer's USB port and browse the files
3814 on that device. You will find '.telem' files in the TeleMetrum
3815 directory that will work with AltosUI directly.
3820 <title>Using Altus Metrum Products</title>
3822 <title>Being Legal</title>
3824 First off, in the US, you need an <ulink url="http://www.altusmetrum.org/Radio/">amateur radio license</ulink> or
3825 other authorization to legally operate the radio transmitters that are part
3830 <title>In the Rocket</title>
3832 In the rocket itself, you just need a flight computer and
3833 a single-cell, 3.7 volt nominal Li-Po rechargeable battery. An
3834 850mAh battery weighs less than a 9V alkaline battery, and will
3835 run a TeleMetrum or TeleMega for hours.
3836 A 110mAh battery weighs less than a triple A battery and is a good
3837 choice for use with TeleMini.
3840 By default, we ship flight computers with a simple wire antenna.
3841 If your electronics bay or the air-frame it resides within is made
3842 of carbon fiber, which is opaque to RF signals, you may prefer to
3843 install an SMA connector so that you can run a coaxial cable to an
3844 antenna mounted elsewhere in the rocket. However, note that the
3845 GPS antenna is fixed on all current products, so you really want
3846 to install the flight computer in a bay made of RF-transparent
3847 materials if at all possible.
3851 <title>On the Ground</title>
3853 To receive the data stream from the rocket, you need an antenna and short
3854 feed-line connected to one of our <ulink url="http://www.altusmetrum.org/TeleDongle/">TeleDongle</ulink> units. If possible, use an SMA to BNC
3855 adapter instead of feedline between the antenna feedpoint and
3856 TeleDongle, as this will give you the best performance. The
3857 TeleDongle in turn plugs directly into the USB port on a notebook
3858 computer. Because TeleDongle looks like a simple serial port, your computer
3859 does not require special device drivers... just plug it in.
3862 The GUI tool, AltosUI, is written in Java and runs across
3863 Linux, Mac OS and Windows. There's also a suite of C tools
3864 for Linux which can perform most of the same tasks.
3867 Alternatively, a TeleBT attached with an SMA to BNC adapter at the
3868 feed point of a hand-held yagi used in conjunction with an Android
3869 device running AltosDroid makes an outstanding ground station.
3872 After the flight, you can use the radio link to extract the more detailed data
3873 logged in either TeleMetrum or TeleMini devices, or you can use a mini USB cable to plug into the
3874 TeleMetrum board directly. Pulling out the data without having to open up
3875 the rocket is pretty cool! A USB cable is also how you charge the Li-Po
3876 battery, so you'll want one of those anyway... the same cable used by lots
3877 of digital cameras and other modern electronic stuff will work fine.
3880 If your rocket lands out of sight, you may enjoy having a hand-held
3881 GPS receiver, so that you can put in a way-point for the last
3882 reported rocket position before touch-down. This makes looking for
3883 your rocket a lot like Geo-Caching... just go to the way-point and
3884 look around starting from there. AltosDroid on an Android device
3885 with GPS receiver works great for this, too!
3888 You may also enjoy having a ham radio “HT” that covers the 70cm band... you
3889 can use that with your antenna to direction-find the rocket on the ground
3890 the same way you can use a Walston or Beeline tracker. This can be handy
3891 if the rocket is hiding in sage brush or a tree, or if the last GPS position
3892 doesn't get you close enough because the rocket dropped into a canyon, or
3893 the wind is blowing it across a dry lake bed, or something like that... Keith
3894 currently uses a Yaesu VX-7R, Bdale has a Baofung UV-5R
3895 which isn't as nice, but was a whole lot cheaper.
3898 So, to recap, on the ground the hardware you'll need includes:
3899 <orderedlist inheritnum='inherit' numeration='arabic'>
3902 an antenna and feed-line or adapter
3917 optionally, a hand-held GPS receiver
3922 optionally, an HT or receiver covering 435 MHz
3928 The best hand-held commercial directional antennas we've found for radio
3929 direction finding rockets are from
3930 <ulink url="http://www.arrowantennas.com/" >
3933 The 440-3 and 440-5 are both good choices for finding a
3934 TeleMetrum- or TeleMini- equipped rocket when used with a suitable
3935 70cm HT. TeleDongle and an SMA to BNC adapter fit perfectly
3936 between the driven element and reflector of Arrow antennas.
3940 <title>Data Analysis</title>
3942 Our software makes it easy to log the data from each flight, both the
3943 telemetry received during the flight itself, and the more
3944 complete data log recorded in the flash memory on the altimeter
3945 board. Once this data is on your computer, our post-flight tools make it
3946 easy to quickly get to the numbers everyone wants, like apogee altitude,
3947 max acceleration, and max velocity. You can also generate and view a
3948 standard set of plots showing the altitude, acceleration, and
3949 velocity of the rocket during flight. And you can even export a TeleMetrum data file
3950 usable with Google Maps and Google Earth for visualizing the flight path
3951 in two or three dimensions!
3954 Our ultimate goal is to emit a set of files for each flight that can be
3955 published as a web page per flight, or just viewed on your local disk with
3960 <title>Future Plans</title>
3962 We've designed a simple GPS based radio tracker called TeleGPS.
3963 If all goes well, we hope to introduce this in the first
3967 We have designed and prototyped several “companion boards” that
3968 can attach to the companion connector on TeleMetrum and TeleMega
3969 flight computers to collect more data, provide more pyro channels,
3970 and so forth. We do not yet know if or when any of these boards
3971 will be produced in enough quantity to sell. If you have specific
3972 interests for data collection or control of events in your rockets
3973 beyond the capabilities of our existing productions, please let
3977 Because all of our work is open, both the hardware designs and the
3978 software, if you have some great idea for an addition to the current
3979 Altus Metrum family, feel free to dive in and help! Or let us know
3980 what you'd like to see that we aren't already working on, and maybe
3981 we'll get excited about it too...
3985 <ulink url="http://altusmetrum.org/">web site</ulink> for more news
3986 and information as our family of products evolves!
3991 <title>Altimeter Installation Recommendations</title>
3993 Building high-power rockets that fly safely is hard enough. Mix
3994 in some sophisticated electronics and a bunch of radio energy
3995 and some creativity and/or compromise may be required. This chapter
3996 contains some suggestions about how to install Altus Metrum
3997 products into a rocket air-frame, including how to safely and
3998 reliably mix a variety of electronics into the same air-frame.
4001 <title>Mounting the Altimeter</title>
4003 The first consideration is to ensure that the altimeter is
4004 securely fastened to the air-frame. For most of our products, we
4005 prefer nylon standoffs and nylon screws; they're good to at least 50G
4006 and cannot cause any electrical issues on the board. Metal screws
4007 and standoffs are fine, too, just be careful to avoid electrical
4008 shorts! For TeleMini v1.0, we usually cut small pieces of 1/16 inch
4010 under the screw holes, and then take 2x56 nylon screws and
4011 screw them through the TeleMini mounting holes, through the
4012 balsa and into the underlying material.
4014 <orderedlist inheritnum='inherit' numeration='arabic'>
4017 Make sure accelerometer-equipped products like TeleMetrum and
4018 TeleMega are aligned precisely along the axis of
4019 acceleration so that the accelerometer can accurately
4020 capture data during the flight.
4025 Watch for any metal touching components on the
4026 board. Shorting out connections on the bottom of the board
4027 can cause the altimeter to fail during flight.
4033 <title>Dealing with the Antenna</title>
4035 The antenna supplied is just a piece of solid, insulated,
4036 wire. If it gets damaged or broken, it can be easily
4037 replaced. It should be kept straight and not cut; bending or
4038 cutting it will change the resonant frequency and/or
4039 impedance, making it a less efficient radiator and thus
4040 reducing the range of the telemetry signal.
4043 Keeping metal away from the antenna will provide better range
4044 and a more even radiation pattern. In most rockets, it's not
4045 entirely possible to isolate the antenna from metal
4046 components; there are often bolts, all-thread and wires from other
4047 electronics to contend with. Just be aware that the more stuff
4048 like this around the antenna, the lower the range.
4051 Make sure the antenna is not inside a tube made or covered
4052 with conducting material. Carbon fiber is the most common
4053 culprit here -- CF is a good conductor and will effectively
4054 shield the antenna, dramatically reducing signal strength and
4055 range. Metallic flake paint is another effective shielding
4056 material which should be avoided around any antennas.
4059 If the ebay is large enough, it can be convenient to simply
4060 mount the altimeter at one end and stretch the antenna out
4061 inside. Taping the antenna to the sled can keep it straight
4062 under acceleration. If there are metal rods, keep the
4063 antenna as far away as possible.
4066 For a shorter ebay, it's quite practical to have the antenna
4067 run through a bulkhead and into an adjacent bay. Drill a small
4068 hole in the bulkhead, pass the antenna wire through it and
4069 then seal it up with glue or clay. We've also used acrylic
4070 tubing to create a cavity for the antenna wire. This works a
4071 bit better in that the antenna is known to stay straight and
4072 not get folded by recovery components in the bay. Angle the
4073 tubing towards the side wall of the rocket and it ends up
4074 consuming very little space.
4077 If you need to place the UHF antenna at a distance from the
4078 altimeter, you can replace the antenna with an edge-mounted
4079 SMA connector, and then run 50Ω coax from the board to the
4080 antenna. Building a remote antenna is beyond the scope of this
4085 <title>Preserving GPS Reception</title>
4087 The GPS antenna and receiver used in TeleMetrum and TeleMega is
4088 highly sensitive and normally have no trouble tracking enough
4089 satellites to provide accurate position information for
4090 recovering the rocket. However, there are many ways the GPS signal
4091 can end up attenuated, negatively affecting GPS performance.
4092 <orderedlist inheritnum='inherit' numeration='arabic'>
4095 Conductive tubing or coatings. Carbon fiber and metal
4096 tubing, or metallic paint will all dramatically attenuate the
4097 GPS signal. We've never heard of anyone successfully
4098 receiving GPS from inside these materials.
4103 Metal components near the GPS patch antenna. These will
4104 de-tune the patch antenna, changing the resonant frequency
4105 away from the L1 carrier and reduce the effectiveness of the
4106 antenna. You can place as much stuff as you like beneath the
4107 antenna as that's covered with a ground plane. But, keep
4108 wires and metal out from above the patch antenna.
4115 <title>Radio Frequency Interference</title>
4117 Any altimeter will generate RFI; the digital circuits use
4118 high-frequency clocks that spray radio interference across a
4119 wide band. Altus Metrum altimeters generate intentional radio
4120 signals as well, increasing the amount of RF energy around the board.
4123 Rocketry altimeters also use precise sensors measuring air
4124 pressure and acceleration. Tiny changes in voltage can cause
4125 these sensor readings to vary by a huge amount. When the
4126 sensors start mis-reporting data, the altimeter can either
4127 fire the igniters at the wrong time, or not fire them at all.
4130 Voltages are induced when radio frequency energy is
4131 transmitted from one circuit to another. Here are things that
4132 influence the induced voltage and current:
4137 Keep wires from different circuits apart. Moving circuits
4138 further apart will reduce RFI.
4143 Avoid parallel wires from different circuits. The longer two
4144 wires run parallel to one another, the larger the amount of
4145 transferred energy. Cross wires at right angles to reduce
4151 Twist wires from the same circuits. Two wires the same
4152 distance from the transmitter will get the same amount of
4153 induced energy which will then cancel out. Any time you have
4154 a wire pair running together, twist the pair together to
4155 even out distances and reduce RFI. For altimeters, this
4156 includes battery leads, switch hookups and igniter
4162 Avoid resonant lengths. Know what frequencies are present
4163 in the environment and avoid having wire lengths near a
4164 natural resonant length. Altus Metrum products transmit on the
4165 70cm amateur band, so you should avoid lengths that are a
4166 simple ratio of that length; essentially any multiple of ¼
4167 of the wavelength (17.5cm).
4173 <title>The Barometric Sensor</title>
4175 Altusmetrum altimeters measure altitude with a barometric
4176 sensor, essentially measuring the amount of air above the
4177 rocket to figure out how high it is. A large number of
4178 measurements are taken as the altimeter initializes itself to
4179 figure out the pad altitude. Subsequent measurements are then
4180 used to compute the height above the pad.
4183 To accurately measure atmospheric pressure, the ebay
4184 containing the altimeter must be vented outside the
4185 air-frame. The vent must be placed in a region of linear
4186 airflow, have smooth edges, and away from areas of increasing or
4187 decreasing pressure.
4190 All barometric sensors are quite sensitive to chemical damage from
4191 the products of APCP or BP combustion, so make sure the ebay is
4192 carefully sealed from any compartment which contains ejection
4197 <title>Ground Testing</title>
4199 The most important aspect of any installation is careful
4200 ground testing. Bringing an air-frame up to the LCO table which
4201 hasn't been ground tested can lead to delays or ejection
4202 charges firing on the pad, or, even worse, a recovery system
4206 Do a 'full systems' test that includes wiring up all igniters
4207 without any BP and turning on all of the electronics in flight
4208 mode. This will catch any mistakes in wiring and any residual
4209 RFI issues that might accidentally fire igniters at the wrong
4210 time. Let the air-frame sit for several minutes, checking for
4211 adequate telemetry signal strength and GPS lock. If any igniters
4212 fire unexpectedly, find and resolve the issue before loading any
4216 Ground test the ejection charges. Prepare the rocket for
4217 flight, loading ejection charges and igniters. Completely
4218 assemble the air-frame and then use the 'Fire Igniters'
4219 interface through a TeleDongle to command each charge to
4220 fire. Make sure the charge is sufficient to robustly separate
4221 the air-frame and deploy the recovery system.
4226 <title>Updating Device Firmware</title>
4228 TeleMega, TeleMetrum v2 and EasyMini are all programmed directly
4229 over their USB connectors (self programming). TeleMetrum v1, TeleMini and
4230 TeleDongle are all programmed by using another device as a
4231 programmer (pair programming). It's important to recognize which
4232 kind of devices you have before trying to reprogram them.
4235 You may wish to begin by ensuring you have current firmware images.
4236 These are distributed as part of the AltOS software bundle that
4237 also includes the AltosUI ground station program. Newer ground
4238 station versions typically work fine with older firmware versions,
4239 so you don't need to update your devices just to try out new
4240 software features. You can always download the most recent
4241 version from <ulink url="http://www.altusmetrum.org/AltOS/"/>.
4244 If you need to update the firmware on a TeleDongle, we recommend
4245 updating the altimeter first, before updating TeleDongle. However,
4246 note that TeleDongle rarely need to be updated. Any firmware version
4247 1.0.1 or later will work, version 1.2.1 may have improved receiver
4248 performance slightly.
4251 Self-programmable devices (TeleMega, TeleMetrum v2 and EasyMini)
4252 are reprogrammed by connecting them to your computer over USB
4256 Updating TeleMega, TeleMetrum v2 or EasyMini Firmware
4258 <orderedlist inheritnum='inherit' numeration='arabic'>
4261 Attach a battery and power switch to the target
4262 device. Power up the device.
4267 Using a Micro USB cable, connect the target device to your
4268 computer's USB socket.
4273 Run AltosUI, and select 'Flash Image' from the File menu.
4278 Select the target device in the Device Selection dialog.
4283 Select the image you want to flash to the device, which
4284 should have a name in the form
4285 <product>-v<product-version>-<software-version>.ihx, such
4286 as TeleMega-v1.0-1.3.0.ihx.
4291 Make sure the configuration parameters are reasonable
4292 looking. If the serial number and/or RF configuration
4293 values aren't right, you'll need to change them.
4298 Hit the 'OK' button and the software should proceed to flash
4299 the device with new firmware, showing a progress bar.
4304 Verify that the device is working by using the 'Configure
4305 Altimeter' item to check over the configuration.
4310 <title>Recovering From Self-Flashing Failure</title>
4312 If the firmware loading fails, it can leave the device
4313 unable to boot. Not to worry, you can force the device to
4314 start the boot loader instead, which will let you try to
4315 flash the device again.
4318 On each device, connecting two pins from one of the exposed
4319 connectors will force the boot loader to start, even if the
4320 regular operating system has been corrupted in some way.
4324 <term>TeleMega</term>
4327 Connect pin 6 and pin 1 of the companion connector. Pin 1
4328 can be identified by the square pad around it, and then
4329 the pins could sequentially across the board. Be very
4330 careful to <emphasis>not</emphasis> short pin 8 to
4331 anything as that is connected directly to the battery. Pin
4332 7 carries 3.3V and the board will crash if that is
4333 connected to pin 1, but shouldn't damage the board.
4338 <term>TeleMetrum v2</term>
4341 Connect pin 6 and pin 1 of the companion connector. Pin 1
4342 can be identified by the square pad around it, and then
4343 the pins could sequentially across the board. Be very
4344 careful to <emphasis>not</emphasis> short pin 8 to
4345 anything as that is connected directly to the battery. Pin
4346 7 carries 3.3V and the board will crash if that is
4347 connected to pin 1, but shouldn't damage the board.
4352 <term>EasyMini</term>
4355 Connect pin 6 and pin 1 of the debug connector, which is
4356 the six holes next to the beeper. Pin 1 can be identified
4357 by the square pad around it, and then the pins could
4358 sequentially across the board, making Pin 6 the one on the
4359 other end of the row.
4367 <title>Pair Programming</title>
4369 The big concept to understand is that you have to use a
4370 TeleMega, TeleMetrum or TeleDongle as a programmer to update a
4371 pair programmed device. Due to limited memory resources in the
4372 cc1111, we don't support programming directly over USB for these
4377 <title>Updating TeleMetrum v1.x Firmware</title>
4378 <orderedlist inheritnum='inherit' numeration='arabic'>
4381 Find the 'programming cable' that you got as part of the starter
4382 kit, that has a red 8-pin MicroMaTch connector on one end and a
4383 red 4-pin MicroMaTch connector on the other end.
4388 Take the 2 screws out of the TeleDongle case to get access
4389 to the circuit board.
4394 Plug the 8-pin end of the programming cable to the
4395 matching connector on the TeleDongle, and the 4-pin end to the
4396 matching connector on the TeleMetrum.
4397 Note that each MicroMaTch connector has an alignment pin that
4398 goes through a hole in the PC board when you have the cable
4404 Attach a battery to the TeleMetrum board.
4409 Plug the TeleDongle into your computer's USB port, and power
4415 Run AltosUI, and select 'Flash Image' from the File menu.
4420 Pick the TeleDongle device from the list, identifying it as the
4426 Select the image you want put on the TeleMetrum, which should have a
4427 name in the form telemetrum-v1.2-1.0.0.ihx. It should be visible
4428 in the default directory, if not you may have to poke around
4429 your system to find it.
4434 Make sure the configuration parameters are reasonable
4435 looking. If the serial number and/or RF configuration
4436 values aren't right, you'll need to change them.
4441 Hit the 'OK' button and the software should proceed to flash
4442 the TeleMetrum with new firmware, showing a progress bar.
4447 Confirm that the TeleMetrum board seems to have updated OK, which you
4448 can do by plugging in to it over USB and using a terminal program
4449 to connect to the board and issue the 'v' command to check
4455 If something goes wrong, give it another try.
4461 <title>Updating TeleMini Firmware</title>
4462 <orderedlist inheritnum='inherit' numeration='arabic'>
4465 You'll need a special 'programming cable' to reprogram the
4466 TeleMini. You can make your own using an 8-pin MicroMaTch
4467 connector on one end and a set of four pins on the other.
4472 Take the 2 screws out of the TeleDongle case to get access
4473 to the circuit board.
4478 Plug the 8-pin end of the programming cable to the matching
4479 connector on the TeleDongle, and the 4-pins into the holes
4480 in the TeleMini circuit board. Note that the MicroMaTch
4481 connector has an alignment pin that goes through a hole in
4482 the PC board when you have the cable oriented correctly, and
4483 that pin 1 on the TeleMini board is marked with a square pad
4484 while the other pins have round pads.
4489 Attach a battery to the TeleMini board.
4494 Plug the TeleDongle into your computer's USB port, and power
4500 Run AltosUI, and select 'Flash Image' from the File menu.
4505 Pick the TeleDongle device from the list, identifying it as the
4511 Select the image you want put on the TeleMini, which should have a
4512 name in the form telemini-v1.0-1.0.0.ihx. It should be visible
4513 in the default directory, if not you may have to poke around
4514 your system to find it.
4519 Make sure the configuration parameters are reasonable
4520 looking. If the serial number and/or RF configuration
4521 values aren't right, you'll need to change them.
4526 Hit the 'OK' button and the software should proceed to flash
4527 the TeleMini with new firmware, showing a progress bar.
4532 Confirm that the TeleMini board seems to have updated OK, which you
4533 can do by configuring it over the radio link through the TeleDongle, or
4534 letting it come up in “flight” mode and listening for telemetry.
4539 If something goes wrong, give it another try.
4545 <title>Updating TeleDongle Firmware</title>
4547 Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
4548 firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
4550 <orderedlist inheritnum='inherit' numeration='arabic'>
4553 Find the 'programming cable' that you got as part of the starter
4554 kit, that has a red 8-pin MicroMaTch connector on one end and a
4555 red 4-pin MicroMaTch connector on the other end.
4560 Find the USB cable that you got as part of the starter kit, and
4561 plug the “mini” end in to the mating connector on TeleMetrum or TeleDongle.
4566 Take the 2 screws out of the TeleDongle case to get access
4567 to the circuit board.
4572 Plug the 8-pin end of the programming cable to the
4573 matching connector on the programmer, and the 4-pin end to the
4574 matching connector on the TeleDongle.
4575 Note that each MicroMaTch connector has an alignment pin that
4576 goes through a hole in the PC board when you have the cable
4582 Attach a battery to the TeleMetrum board if you're using one.
4587 Plug both the programmer and the TeleDongle into your computer's USB
4588 ports, and power up the programmer.
4593 Run AltosUI, and select 'Flash Image' from the File menu.
4598 Pick the programmer device from the list, identifying it as the
4604 Select the image you want put on the TeleDongle, which should have a
4605 name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
4606 in the default directory, if not you may have to poke around
4607 your system to find it.
4612 Make sure the configuration parameters are reasonable
4613 looking. If the serial number and/or RF configuration
4614 values aren't right, you'll need to change them. The TeleDongle
4615 serial number is on the “bottom” of the circuit board, and can
4616 usually be read through the translucent blue plastic case without
4617 needing to remove the board from the case.
4622 Hit the 'OK' button and the software should proceed to flash
4623 the TeleDongle with new firmware, showing a progress bar.
4628 Confirm that the TeleDongle board seems to have updated OK, which you
4629 can do by plugging in to it over USB and using a terminal program
4630 to connect to the board and issue the 'v' command to check
4631 the version, etc. Once you're happy, remove the programming cable
4632 and put the cover back on the TeleDongle.
4637 If something goes wrong, give it another try.
4642 Be careful removing the programming cable from the locking 8-pin
4643 connector on TeleMetrum. You'll need a fingernail or perhaps a thin
4644 screwdriver or knife blade to gently pry the locking ears out
4645 slightly to extract the connector. We used a locking connector on
4646 TeleMetrum to help ensure that the cabling to companion boards
4647 used in a rocket don't ever come loose accidentally in flight.
4652 <title>Hardware Specifications</title>
4655 TeleMega Specifications
4660 Recording altimeter for model rocketry.
4665 Supports dual deployment and four auxiliary pyro channels
4666 (a total of 6 events).
4671 70cm 40mW ham-band transceiver for telemetry down-link.
4676 Barometric pressure sensor good to 100k feet MSL.
4681 1-axis high-g accelerometer for motor characterization, capable of
4687 9-axis IMU including integrated 3-axis accelerometer,
4688 3-axis gyroscope and 3-axis magnetometer.
4693 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
4698 On-board 8 Megabyte non-volatile memory for flight data storage.
4703 USB interface for battery charging, configuration, and data recovery.
4708 Fully integrated support for Li-Po rechargeable batteries.
4713 Can use either main system Li-Po or optional separate pyro battery
4719 3.25 x 1.25 inch board designed to fit inside 38mm air-frame coupler tube.
4726 TeleMetrum v2 Specifications
4731 Recording altimeter for model rocketry.
4736 Supports dual deployment (can fire 2 ejection charges).
4741 70cm, 40mW ham-band transceiver for telemetry down-link.
4746 Barometric pressure sensor good to 100k feet MSL.
4751 1-axis high-g accelerometer for motor characterization, capable of
4757 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
4762 On-board 8 Megabyte non-volatile memory for flight data storage.
4767 USB interface for battery charging, configuration, and data recovery.
4772 Fully integrated support for Li-Po rechargeable batteries.
4777 Uses Li-Po to fire e-matches, can be modified to support
4778 optional separate pyro battery if needed.
4783 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
4789 <title>TeleMetrum v1 Specifications</title>
4793 Recording altimeter for model rocketry.
4798 Supports dual deployment (can fire 2 ejection charges).
4803 70cm, 10mW ham-band transceiver for telemetry down-link.
4808 Barometric pressure sensor good to 45k feet MSL.
4813 1-axis high-g accelerometer for motor characterization, capable of
4814 +/- 50g using default part.
4819 On-board, integrated GPS receiver with 5Hz update rate capability.
4824 On-board 1 megabyte non-volatile memory for flight data storage.
4829 USB interface for battery charging, configuration, and data recovery.
4834 Fully integrated support for Li-Po rechargeable batteries.
4839 Uses Li-Po to fire e-matches, can be modified to support
4840 optional separate pyro battery if needed.
4845 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
4852 TeleMini v2.0 Specifications
4857 Recording altimeter for model rocketry.
4862 Supports dual deployment (can fire 2 ejection charges).
4867 70cm, 10mW ham-band transceiver for telemetry down-link.
4872 Barometric pressure sensor good to 100k feet MSL.
4877 On-board 1 megabyte non-volatile memory for flight data storage.
4882 USB interface for configuration, and data recovery.
4887 Support for Li-Po rechargeable batteries (using an
4888 external charger), or any 3.7-15V external battery.
4893 Uses Li-Po to fire e-matches, can be modified to support
4894 optional separate pyro battery if needed.
4899 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
4906 TeleMini v1.0 Specifications
4911 Recording altimeter for model rocketry.
4916 Supports dual deployment (can fire 2 ejection charges).
4921 70cm, 10mW ham-band transceiver for telemetry down-link.
4926 Barometric pressure sensor good to 45k feet MSL.
4931 On-board 5 kilobyte non-volatile memory for flight data storage.
4936 RF interface for configuration, and data recovery.
4941 Support for Li-Po rechargeable batteries, using an external charger.
4946 Uses Li-Po to fire e-matches, can be modified to support
4947 optional separate pyro battery if needed.
4952 1.5 x .5 inch board designed to fit inside 18mm air-frame coupler tube.
4959 EasyMini Specifications
4964 Recording altimeter for model rocketry.
4969 Supports dual deployment (can fire 2 ejection charges).
4974 Barometric pressure sensor good to 100k feet MSL.
4979 On-board 1 megabyte non-volatile memory for flight data storage.
4984 USB interface for configuration, and data recovery.
4989 Support for Li-Po rechargeable batteries (using an
4990 external charger), or any 3.7-15V external battery.
4995 Uses Li-Po to fire e-matches, can be modified to support
4996 optional separate pyro battery if needed.
5001 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
5010 <emphasis>TeleMetrum seems to shut off when disconnected from the
5011 computer.</emphasis> <?linebreak?>
5012 Make sure the battery is adequately charged. Remember the
5013 unit will pull more power than the USB port can deliver before the
5014 GPS enters “locked” mode. The battery charges best when TeleMetrum
5018 <emphasis>It's impossible to stop the TeleDongle when it's in “p” mode, I have
5019 to unplug the USB cable? </emphasis><?linebreak?>
5020 Make sure you have tried to “escape out” of
5021 this mode. If this doesn't work the reboot procedure for the
5022 TeleDongle *is* to simply unplug it. 'cu' however will retain it's
5023 outgoing buffer IF your “escape out” ('~~') does not work.
5024 At this point using either 'ao-view' (or possibly
5025 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
5029 <emphasis>The amber LED (on the TeleMetrum) lights up when both
5030 battery and USB are connected. Does this mean it's charging?
5031 </emphasis><?linebreak?>
5032 Yes, the yellow LED indicates the charging at the 'regular' rate.
5033 If the led is out but the unit is still plugged into a USB port,
5034 then the battery is being charged at a 'trickle' rate.
5037 <emphasis>There are no “dit-dah-dah-dit” sound or lights like the manual
5038 mentions?</emphasis><?linebreak?>
5039 That's the “pad” mode. Weak batteries might be the problem.
5040 It is also possible that the flight computer is horizontal and the
5042 is instead a “dit-dit” meaning 'idle'. For TeleMini, it's possible that
5043 it received a command packet which would have left it in “pad” mode.
5046 <emphasis>How do I save flight data?</emphasis><?linebreak?>
5047 Live telemetry is written to file(s) whenever AltosUI is connected
5048 to the TeleDongle. The file area defaults to ~/TeleMetrum
5049 but is easily changed using the menus in AltosUI. The files that
5050 are written end in '.telem'. The after-flight
5051 data-dumped files will end in .eeprom and represent continuous data
5052 unlike the .telem files that are subject to losses
5053 along the RF data path.
5054 See the above instructions on what and how to save the eeprom stored
5055 data after physically retrieving your altimeter. Make sure to save
5056 the on-board data after each flight; while the TeleMetrum can store
5057 multiple flights, you never know when you'll lose the altimeter...
5061 <title>Notes for Older Software</title>
5064 Before AltosUI was written, using Altus Metrum devices required
5065 some finesse with the Linux command line. There was a limited
5066 GUI tool, ao-view, which provided functionality similar to the
5067 Monitor Flight window in AltosUI, but everything else was a
5068 fairly 80's experience. This appendix includes documentation for
5069 using that software.
5073 Both TeleMetrum and TeleDongle can be directly communicated
5074 with using USB ports. The first thing you should try after getting
5075 both units plugged into to your computer's USB port(s) is to run
5076 'ao-list' from a terminal-window to see what port-device-name each
5077 device has been assigned by the operating system.
5078 You will need this information to access the devices via their
5079 respective on-board firmware and data using other command line
5080 programs in the AltOS software suite.
5083 TeleMini can be communicated with through a TeleDongle device
5084 over the radio link. When first booted, TeleMini listens for a
5085 TeleDongle device and if it receives a packet, it goes into
5086 'idle' mode. Otherwise, it goes into 'pad' mode and waits to be
5087 launched. The easiest way to get it talking is to start the
5088 communication link on the TeleDongle and the power up the
5092 To access the device's firmware for configuration you need a terminal
5093 program such as you would use to talk to a modem. The software
5094 authors prefer using the program 'cu' which comes from the UUCP package
5095 on most Unix-like systems such as Linux. An example command line for
5096 cu might be 'cu -l /dev/ttyACM0', substituting the correct number
5097 indicated from running the
5098 ao-list program. Another reasonable terminal program for Linux is
5099 'cutecom'. The default 'escape'
5100 character used by CU (i.e. the character you use to
5101 issue commands to cu itself instead of sending the command as input
5102 to the connected device) is a '~'. You will need this for use in
5103 only two different ways during normal operations. First is to exit
5104 the program by sending a '~.' which is called a 'escape-disconnect'
5105 and allows you to close-out from 'cu'. The
5106 second use will be outlined later.
5109 All of the Altus Metrum devices share the concept of a two level
5110 command set in their firmware.
5111 The first layer has several single letter commands. Once
5112 you are using 'cu' (or 'cutecom') sending (typing) a '?'
5113 returns a full list of these
5114 commands. The second level are configuration sub-commands accessed
5115 using the 'c' command, for
5116 instance typing 'c?' will give you this second level of commands
5117 (all of which require the
5118 letter 'c' to access). Please note that most configuration options
5119 are stored only in Flash memory; TeleDongle doesn't provide any storage
5120 for these options and so they'll all be lost when you unplug it.
5123 Try setting these configuration ('c' or second level menu) values. A good
5124 place to start is by setting your call sign. By default, the boards
5125 use 'N0CALL' which is cute, but not exactly legal!
5126 Spend a few minutes getting comfortable with the units, their
5127 firmware, and 'cu' (or possibly 'cutecom').
5128 For instance, try to send
5129 (type) a 'c r 2' and verify the channel change by sending a 'c s'.
5130 Verify you can connect and disconnect from the units while in your
5131 terminal program by sending the escape-disconnect mentioned above.
5134 To set the radio frequency, use the 'c R' command to specify the
5135 radio transceiver configuration parameter. This parameter is computed
5136 using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
5137 the standard calibration reference frequency, 'S', (normally 434.550MHz):
5141 Round the result to the nearest integer value.
5142 As with all 'c' sub-commands, follow this with a 'c w' to write the
5143 change to the parameter block in the on-board flash on
5144 your altimeter board if you want the change to stay in place across reboots.
5147 To set the apogee delay, use the 'c d' command.
5148 As with all 'c' sub-commands, follow this with a 'c w' to write the
5149 change to the parameter block in the on-board DataFlash chip.
5152 To set the main deployment altitude, use the 'c m' command.
5153 As with all 'c' sub-commands, follow this with a 'c w' to write the
5154 change to the parameter block in the on-board DataFlash chip.
5157 To calibrate the radio frequency, connect the UHF antenna port to a
5158 frequency counter, set the board to 434.550MHz, and use the 'C'
5159 command to generate a CW carrier. Wait for the transmitter temperature
5160 to stabilize and the frequency to settle down.
5161 Then, divide 434.550 MHz by the
5162 measured frequency and multiply by the current radio cal value show
5163 in the 'c s' command. For an unprogrammed board, the default value
5164 is 1186611 for cc1111 based products and 7119667 for cc1120
5165 based products. Take the resulting integer and program it using the 'c f'
5166 command. Testing with the 'C' command again should show a carrier
5167 within a few tens of Hertz of the intended frequency.
5168 As with all 'c' sub-commands, follow this with a 'c w' to write the
5169 change to the configuration memory.
5172 Note that the 'reboot' command, which is very useful on the altimeters,
5173 will likely just cause problems with the dongle. The *correct* way
5174 to reset the dongle is just to unplug and re-plug it.
5177 A fun thing to do at the launch site and something you can do while
5178 learning how to use these units is to play with the radio link access
5179 between an altimeter and the TeleDongle. Be aware that you *must* create
5180 some physical separation between the devices, otherwise the link will
5181 not function due to signal overload in the receivers in each device.
5184 Now might be a good time to take a break and read the rest of this
5185 manual, particularly about the two “modes” that the altimeters
5186 can be placed in. TeleMetrum uses the position of the device when booting
5187 up will determine whether the unit is in “pad” or “idle” mode. TeleMini
5188 enters “idle” mode when it receives a command packet within the first 5 seconds
5189 of being powered up, otherwise it enters “pad” mode.
5192 You can access an altimeter in idle mode from the TeleDongle's USB
5193 connection using the radio link
5194 by issuing a 'p' command to the TeleDongle. Practice connecting and
5195 disconnecting ('~~' while using 'cu') from the altimeter. If
5196 you cannot escape out of the “p” command, (by using a '~~' when in
5197 CU) then it is likely that your kernel has issues. Try a newer version.
5200 Using this radio link allows you to configure the altimeter, test
5201 fire e-matches and igniters from the flight line, check pyro-match
5202 continuity and so forth. You can leave the unit turned on while it
5203 is in 'idle mode' and then place the
5204 rocket vertically on the launch pad, walk away and then issue a
5205 reboot command. The altimeter will reboot and start sending data
5206 having changed to the “pad” mode. If the TeleDongle is not receiving
5207 this data, you can disconnect 'cu' from the TeleDongle using the
5208 procedures mentioned above and THEN connect to the TeleDongle from
5209 inside 'ao-view'. If this doesn't work, disconnect from the
5210 TeleDongle, unplug it, and try again after plugging it back in.
5213 In order to reduce the chance of accidental firing of pyrotechnic
5214 charges, the command to fire a charge is intentionally somewhat
5215 difficult to type, and the built-in help is slightly cryptic to
5216 prevent accidental echoing of characters from the help text back at
5217 the board from firing a charge. The command to fire the apogee
5218 drogue charge is 'i DoIt drogue' and the command to fire the main
5219 charge is 'i DoIt main'.
5222 On TeleMetrum, the GPS will eventually find enough satellites, lock in on them,
5223 and 'ao-view' will both auditorily announce and visually indicate
5225 Now you can launch knowing that you have a good data path and
5226 good satellite lock for flight data and recovery. Remember
5227 you MUST tell ao-view to connect to the TeleDongle explicitly in
5228 order for ao-view to be able to receive data.
5231 The altimeters provide RDF (radio direction finding) tones on
5232 the pad, during descent and after landing. These can be used to
5233 locate the rocket using a directional antenna; the signal
5234 strength providing an indication of the direction from receiver to rocket.
5237 TeleMetrum also provides GPS tracking data, which can further simplify
5238 locating the rocket once it has landed. (The last good GPS data
5239 received before touch-down will be on the data screen of 'ao-view'.)
5242 Once you have recovered the rocket you can download the eeprom
5243 contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
5244 either a USB cable or over the radio link using TeleDongle.
5245 And by following the man page for 'ao-postflight' you can create
5246 various data output reports, graphs, and even KML data to see the
5247 flight trajectory in Google-earth. (Moving the viewing angle making
5248 sure to connect the yellow lines while in Google-earth is the proper
5252 As for ao-view.... some things are in the menu but don't do anything
5253 very useful. The developers have stopped working on ao-view to focus
5254 on a new, cross-platform ground station program. So ao-view may or
5255 may not be updated in the future. Mostly you just use
5256 the Log and Device menus. It has a wonderful display of the incoming
5257 flight data and I am sure you will enjoy what it has to say to you
5258 once you enable the voice output!
5262 <title>Drill Templates</title>
5264 These images, when printed, provide precise templates for the
5265 mounting holes in Altus Metrum flight computers
5268 <title>TeleMega template</title>
5270 TeleMega has overall dimensions of 1.250 x 3.250 inches, and
5271 the mounting holes are sized for use with 4-40 or M3 screws.
5274 <mediaobject id="TeleMegaTemplate">
5276 <imagedata format="SVG" fileref="telemega.svg"
5277 scalefit="0" scale="100" align="center" />
5283 <title>TeleMetrum template</title>
5285 TeleMetrum has overall dimensions of 1.000 x 2.750 inches, and the
5286 mounting holes are sized for use with 4-40 or M3 screws.
5289 <mediaobject id="TeleMetrumTemplate">
5291 <imagedata format="SVG" fileref="telemetrum.svg"
5292 scalefit="0" scale="100" align="center" />
5298 <title>TeleMini v2/EasyMini template</title>
5300 TeleMini v2 and EasyMini have overall dimensions of 0.800 x 1.500 inches, and the
5301 mounting holes are sized for use with 4-40 or M3 screws.
5304 <mediaobject id="MiniTemplate">
5306 <imagedata format="SVG" fileref="easymini.svg"
5307 scalefit="0" scale="100" align="center" />
5313 <title>TeleMini v1 template</title>
5315 TeleMini has overall dimensions of 0.500 x 1.500 inches, and the
5316 mounting holes are sized for use with 2-56 or M2 screws.
5319 <mediaobject id="TeleMiniTemplate">
5321 <imagedata format="SVG" fileref="telemini.svg"
5322 scalefit="0" scale="100" align="center" />
5329 <title>Calibration</title>
5331 There are only two calibrations required for TeleMetrum and
5332 TeleMega, and only one for TeleDongle, TeleMini and EasyMini.
5333 All boards are shipped from the factory pre-calibrated, but
5334 the procedures are documented here in case they are ever
5335 needed. Re-calibration is not supported by AltosUI, you must
5336 connect to the board with a serial terminal program and
5337 interact directly with the on-board command interpreter to
5341 <title>Radio Frequency</title>
5343 The radio frequency is synthesized from a clock based on the
5344 crystal on the board. The actual frequency of this oscillator
5345 must be measured to generate a calibration constant. While our
5347 bandwidth is wide enough to allow boards to communicate even when
5348 their oscillators are not on exactly the same frequency, performance
5349 is best when they are closely matched.
5350 Radio frequency calibration requires a calibrated frequency counter.
5351 Fortunately, once set, the variation in frequency due to aging and
5352 temperature changes is small enough that re-calibration by customers
5353 should generally not be required.
5356 To calibrate the radio frequency, connect the UHF antenna
5357 port to a frequency counter, set the board to 434.550MHz,
5358 and use the 'C' command in the on-board command interpreter
5359 to generate a CW carrier. For USB-enabled boards, this is
5360 best done over USB. For TeleMini v1, note that the only way
5361 to escape the 'C' command is via power cycle since the board
5362 will no longer be listening for commands once it starts
5363 generating a CW carrier.
5366 Wait for the transmitter temperature to stabilize and the frequency
5367 to settle down. Then, divide 434.550 MHz by the
5368 measured frequency and multiply by the current radio cal value show
5369 in the 'c s' command. For an unprogrammed board, the default value
5370 is 1186611. Take the resulting integer and program it using the 'c f'
5371 command. Testing with the 'C' command again should show a carrier
5372 within a few tens of Hertz of the intended frequency.
5373 As with all 'c' sub-commands, follow this with a 'c w' to write the
5374 change to the parameter block in the on-board storage chip.
5377 Note that any time you re-do the radio frequency calibration, the
5378 radio frequency is reset to the default 434.550 Mhz. If you want
5379 to use another frequency, you will have to set that again after
5380 calibration is completed.
5384 <title>TeleMetrum and TeleMega Accelerometers</title>
5386 While barometric sensors are factory-calibrated,
5387 accelerometers are not, and so each must be calibrated once
5388 installed in a flight computer. Explicitly calibrating the
5389 accelerometers also allows us to load any compatible device.
5390 We perform a two-point calibration using gravity.
5393 To calibrate the acceleration sensor, use the 'c a 0' command. You
5394 will be prompted to orient the board vertically with the UHF antenna
5395 up and press a key, then to orient the board vertically with the
5396 UHF antenna down and press a key. Note that the accuracy of this
5397 calibration depends primarily on how perfectly vertical and still
5398 the board is held during the cal process. As with all 'c'
5399 sub-commands, follow this with a 'c w' to write the
5400 change to the parameter block in the on-board DataFlash chip.
5403 The +1g and -1g calibration points are included in each telemetry
5404 frame and are part of the header stored in onboard flash to be
5405 downloaded after flight. We always store and return raw ADC
5406 samples for each sensor... so nothing is permanently “lost” or
5407 “damaged” if the calibration is poor.
5410 In the unlikely event an accel cal goes badly, it is possible
5411 that TeleMetrum or TeleMega may always come up in 'pad mode'
5412 and as such not be listening to either the USB or radio link.
5413 If that happens, there is a special hook in the firmware to
5414 force the board back in to 'idle mode' so you can re-do the
5415 cal. To use this hook, you just need to ground the SPI clock
5416 pin at power-on. This pin is available as pin 2 on the 8-pin
5417 companion connector, and pin 1 is ground. So either
5418 carefully install a fine-gauge wire jumper between the two
5419 pins closest to the index hole end of the 8-pin connector, or
5420 plug in the programming cable to the 8-pin connector and use
5421 a small screwdriver or similar to short the two pins closest
5422 to the index post on the 4-pin end of the programming cable,
5423 and power up the board. It should come up in 'idle mode'
5424 (two beeps), allowing a re-cal.
5429 <title>Release Notes</title>
5431 <title>Version 1.4.2</title>
5433 xmlns:xi="http://www.w3.org/2001/XInclude"
5434 href="release-notes-1.4.2.xsl"
5435 xpointer="xpointer(/article/*)"/>
5438 <title>Version 1.4.1</title>
5440 xmlns:xi="http://www.w3.org/2001/XInclude"
5441 href="release-notes-1.4.1.xsl"
5442 xpointer="xpointer(/article/*)"/>
5445 <title>Version 1.4</title>
5447 xmlns:xi="http://www.w3.org/2001/XInclude"
5448 href="release-notes-1.4.xsl"
5449 xpointer="xpointer(/article/*)"/>
5452 <title>Version 1.3.2</title>
5454 xmlns:xi="http://www.w3.org/2001/XInclude"
5455 href="release-notes-1.3.2.xsl"
5456 xpointer="xpointer(/article/*)"/>
5459 <title>Version 1.3.1</title>
5461 xmlns:xi="http://www.w3.org/2001/XInclude"
5462 href="release-notes-1.3.1.xsl"
5463 xpointer="xpointer(/article/*)"/>
5466 <title>Version 1.3</title>
5468 xmlns:xi="http://www.w3.org/2001/XInclude"
5469 href="release-notes-1.3.xsl"
5470 xpointer="xpointer(/article/*)"/>
5473 <title>Version 1.2.1</title>
5475 xmlns:xi="http://www.w3.org/2001/XInclude"
5476 href="release-notes-1.2.1.xsl"
5477 xpointer="xpointer(/article/*)"/>
5480 <title>Version 1.2</title>
5482 xmlns:xi="http://www.w3.org/2001/XInclude"
5483 href="release-notes-1.2.xsl"
5484 xpointer="xpointer(/article/*)"/>
5487 <title>Version 1.1.1</title>
5489 xmlns:xi="http://www.w3.org/2001/XInclude"
5490 href="release-notes-1.1.1.xsl"
5491 xpointer="xpointer(/article/*)"/>
5494 <title>Version 1.1</title>
5496 xmlns:xi="http://www.w3.org/2001/XInclude"
5497 href="release-notes-1.1.xsl"
5498 xpointer="xpointer(/article/*)"/>
5501 <title>Version 1.0.1</title>
5503 xmlns:xi="http://www.w3.org/2001/XInclude"
5504 href="release-notes-1.0.1.xsl"
5505 xpointer="xpointer(/article/*)"/>
5508 <title>Version 0.9.2</title>
5510 xmlns:xi="http://www.w3.org/2001/XInclude"
5511 href="release-notes-0.9.2.xsl"
5512 xpointer="xpointer(/article/*)"/>
5515 <title>Version 0.9</title>
5517 xmlns:xi="http://www.w3.org/2001/XInclude"
5518 href="release-notes-0.9.xsl"
5519 xpointer="xpointer(/article/*)"/>
5522 <title>Version 0.8</title>
5524 xmlns:xi="http://www.w3.org/2001/XInclude"
5525 href="release-notes-0.8.xsl"
5526 xpointer="xpointer(/article/*)"/>
5529 <title>Version 0.7.1</title>
5531 xmlns:xi="http://www.w3.org/2001/XInclude"
5532 href="release-notes-0.7.1.xsl"
5533 xpointer="xpointer(/article/*)"/>
5538 <!-- LocalWords: Altusmetrum
projects / fw / altos / blob