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>TeleGPS Owner's Manual</title>
6 <subtitle>A recording GPS tracker</subtitle>
9 <firstname>Keith</firstname>
10 <surname>Packard</surname>
14 <holder>Bdale Garbee and Keith Packard</holder>
18 <imagedata fileref="telegps-v1.0-top.jpg" width="4in"/>
23 This document is released under the terms of the
24 <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
25 Creative Commons ShareAlike 3.0
32 <revnumber>1.4.1</revnumber>
33 <date>20 June 2014</date>
35 Minor release fixing some installation bugs.
39 <revnumber>1.4</revnumber>
40 <date>13 June 2014</date>
48 <title>Acknowledgements</title>
50 Have fun using these products, and we hope to meet all of you
51 out on the rocket flight line somewhere.
54 NAR #87103, TRA #12201
57 NAR #88757, TRA #12200
62 <title>Quick Start Guide</title>
64 TeleGPS is designed to be easy to use. Requiring no external
65 components, flying takes just a few steps.
68 First, download and install the software from <ulink
69 url="http://altusmetrum.org/AltOS"/>. This will make sure that
70 you have the right device drivers installed.
73 Next, plug in the battery and USB cable and connect TeleGPS to
74 your computer. This will charge the battery and allow you to
78 Start the TeleGPS application and set the callsign and frequency
79 on your TeleGPS device; refer to the Configure TeleGPS section
80 in the TeleGPS Application chapter for instructions.
83 Unplug TeleGPS when the battery charger light goes green. This
84 will enable the radio and logging portions of the TeleGPS
88 Connect TeleDongle to your computer and start TeleGPS or start
89 AltosDroid on your android device and connect to TeleBT. Set the
90 frequency to match the TeleGPS and you should be receiving telemetry.
94 <title>Handling Precautions</title>
96 All Altus Metrum products are sophisticated electronic devices.
97 When handled gently and properly installed in an air-frame, they
98 will deliver impressive results. However, as with all electronic
99 devices, there are some precautions you must take.
102 The Lithium polymer batteries have an
103 extraordinary power density. This is great because we can fly with
104 much less battery mass... but if they are punctured
105 or their contacts are allowed to short, they can and will release their
107 Thus we recommend that you take some care when handling TeleGPS
108 to keep conductive material from coming in contact with the exposed metal elements.
111 As with all other rocketry electronics, Altus Metrum devices must
112 be protected from exposure to corrosive motor exhaust and ejection
117 <title>TeleGPS Hardware</title>
119 <title>Hooking Up Lithium Polymer Batteries</title>
121 TeleGPS has a two pin JST PH series connector to connect up
122 a single-cell Lithium Polymer cell (3.7V nominal). You can
123 purchase matching batteries from the Altus Metrum store, or
124 other vendors, or you can make your own. Pin 1 of the
125 connector is positive, pin 2 is negative. Spark Fun sells a
126 cable with the connector attached, which they call a <ulink
127 url="https://www.sparkfun.com/products/9914">JST Jumper 2
128 Wire Assembly</ulink>.
131 Many RC vendors also sell lithium polymer batteries with
132 this same connector. All that we have found use the opposite
133 polarity, and if you use them that way, you will damage or
138 <title>On-board Data Recording</title>
140 TeleGPS logs GPS data at a user-configurable rate. Data are
141 logged to a 2MB on-board flash memory part, which can be
142 partitioned into several equal-sized blocks, one for each
143 flight. 64kB of this storage are reserved to hold
144 configuration data, leaving 1984kB for flight data.
147 The on-board flash is partitioned into separate flight logs,
148 each of a fixed maximum size. Increase the maximum size of
149 each log and you reduce the number of flights that can be
150 stored. Decrease the size and you can store more flights.
153 To compute the amount of space needed for a single log, you
154 can divide the expected time (in seconds) by the sample period
155 (by default, 1 second per sample) and then multiply the result
156 by 32 bytes per sample. For instance, a sample period of 1
157 second and a flight lasting one hour will take 32 * 3600 =
158 115200 bytes. TeleGPS does try to reduce log space used by not
159 recording position information when it isn't moving, so actual
160 space consumed may be less than this.
163 The default size allows for four flights of 496kB each, which
164 provides over four hours of logging at 1 sample per second.
167 TeleGPS will not overwrite existing flight data, so be sure to
168 download flight data and erase it from the onboard flash
169 before it fills up. TeleGPS will still report telemetry even
170 if memory is full, so the only thing you will lose is the
175 <title>Installation</title>
177 The battery connectors are a standard 2-pin JST connector and
178 match batteries sold by Spark Fun. These batteries are
179 single-cell Lithium Polymer batteries that nominally provide 3.7
180 volts. Other vendors sell similar batteries for RC aircraft
181 using mating connectors, however the polarity for those is
182 generally reversed from the batteries used by Altus Metrum
183 products. In particular, the Tenergy batteries supplied for use
184 in Featherweight flight computers are not compatible with Altus
185 Metrum flight computers or battery chargers. <emphasis>Check
186 polarity and voltage before connecting any battery not purchased
187 from Altus Metrum or Spark Fun.</emphasis>
190 TeleGPS uses an integrate GPS patch antenna and won't
191 receive GPS signals if installed inside a metal or carbon
192 fiber compartment. Test GPS reception and telemetry
193 transmission with the system installed and all other
194 electronics powered up to verify signal reception and make
195 sure there isn't any interference from other systems.
200 <title>System Operation</title>
202 <title>GFSK Telemetry</title>
204 TeleGPS's native telemetry system doesn't use a 'normal packet
205 radio' mode like APRS because it's not very efficient. The
206 GFSK modulation we use is FSK with the base-band pulses passed
207 through a Gaussian filter before they go into the modulator to
208 limit the transmitted bandwidth. When combined with forward
209 error correction and interleaving, this allows us to have a
210 very robust 19.2 kilobit data link with only 10-40 milliwatts
211 of transmit power, a whip antenna in the rocket, and a
212 hand-held Yagi on the ground. We've had flights to above 21k
213 feet AGL with great reception, and calculations suggest we
214 should be good to well over 40k feet AGL with a 5-element yagi
215 on the ground with our 10mW units and over 100k feet AGL with
222 TeleGPS can send APRS if desired, and the
223 interval between APRS packets can be configured. As each APRS
224 packet takes a full second to transmit, we recommend an
225 interval of at least 5 seconds to avoid consuming too much
226 battery power or radio channel bandwidth. You can configure
227 the APRS interval using AltosUI; that process is described in
228 the Configure Altimeter section of the AltosUI chapter.
231 AltOS uses the APRS compressed position report data format,
232 which provides for higher position precision and shorter
233 packets than the original APRS format. It also includes
234 altitude data, which is invaluable when tracking rockets. We
235 haven't found a receiver which doesn't handle compressed
236 positions, but it's just possible that you have one, so if you
237 have an older device that can receive the raw packets but
238 isn't displaying position information, it's possible that this
242 The APRS packet format includes a comment field that can have
243 arbitrary text in it. AltOS uses this to send status
244 information about the flight computer. It sends four fields as
245 shown in the following table.
248 <title>Altus Metrum APRS Comments</title>
249 <?dbfo keep-together="always"?>
250 <tgroup cols='3' align='center' colsep='1' rowsep='1'>
251 <colspec align='center' colwidth='*' colname='Field'/>
252 <colspec align='center' colwidth='*' colname='Example'/>
253 <colspec align='center' colwidth='4*' colname='Description'/>
256 <entry align='center'>Field</entry>
257 <entry align='center'>Example</entry>
258 <entry align='center'>Description</entry>
265 <entry>GPS Status U for unlocked, L for locked</entry>
270 <entry>Number of Satellites in View</entry>
275 <entry>Battery Voltage</entry>
281 Here's an example of an APRS comment showing GPS lock with 6
282 satellites in view and a battery at 4.0V.
288 Make sure your primary battery is above 3.8V and GPS is locked
289 with at least 5 or 6 satellites in view before starting. If GPS
290 is switching between L and U regularly, then it doesn't have a
291 good lock and you should wait until it becomes stable.
294 If the GPS receiver loses lock, the APRS data transmitted will
295 contain the last position for which GPS lock was
296 available. You can tell that this has happened by noticing
297 that the GPS status character switches from 'L' to 'U'. Before
298 GPS has locked, APRS will transmit zero for latitude,
299 longitude and altitude.
303 <title>Configurable Parameters</title>
305 Configuring TeleGPS is very
306 simple; the few configurable parameters can all be set
307 using the TeleGPS application over USB. Read
308 the Configure TeleGPS section in the TeleGPS Software chapter below
309 for more information.
312 <title>Radio Frequency</title>
314 Altus Metrum boards support radio frequencies in the 70cm
315 band. By default, the configuration interface provides a
316 list of 10 “standard” frequencies in 100kHz channels starting at
317 434.550MHz. However, the firmware supports use of
318 any 50kHz multiple within the 70cm band. At any given
319 launch, we highly recommend coordinating when and by whom each
320 frequency will be used to avoid interference. And of course, both
321 TeleGPS and the receiver must be configured to the same
322 frequency to successfully communicate with each other.
326 <title>Callsign</title>
328 This sets the callsign used for telemetry and APRS to
333 <title>Telemetry/RDF/APRS Enable</title>
335 You can completely disable the radio, if necessary, leaving
336 TeleGPS only logging data to internal memory.
340 <title>APRS Interval</title>
342 This selects how often APRS packets are transmitted. Set
343 this to zero to disable APRS without also disabling the
344 regular telemetry and RDF transmissions. As APRS takes a
345 full second to transmit a single position report, we
346 recommend sending packets no more than once every 5 seconds.
350 <title>Maximum Flight Log</title>
352 Changing this value will set the maximum amount of flight
353 log storage that an individual flight will use. The
354 available storage is divided into as many flights of the
355 specified size as can fit in the available space. You can
356 download and erase individual flight logs. If you fill up
357 the available storage, future flights will not get logged
358 until you erase some of the stored ones.
362 <title>Logging Trigger Motion</title>
364 If TeleGPS moves less than this distance over a long period
365 of time, it will not log that location, saving storage space.
369 <title>Position Reporting Interval</title>
371 This sets how often TeleGPS reports position information via
372 telemetry and to the on-board log. Reducing this value will
373 save power and logging memory consumption.
379 <title>TeleGPS Application</title>
381 The TeleGPS application provides a graphical user interface for
382 interacting with the Altus Metrum product family. TeleGPS can
383 monitor telemetry data, configure devices and many other
384 tasks. The primary interface window is for displaying data
385 received over the telemetry link. There are additional
386 tasks available from the main window menu bar. This chapter
387 is split into sections, each of which documents one of the tasks
388 provided from the top-level toolbar.
391 <title>Telemetry Monitoring</title>
393 This is the window brought up when you start the
394 application. If you have a TeleDongle device connected to the
395 computer, it will automatically be selected for telemetry monitoring
398 All telemetry data received are automatically recorded in
399 suitable log files. The name of the files includes the current
400 date and TeleGPS serial and flight numbers.
403 The radio frequency being monitored by the TeleDongle device
404 is displayed at the top of the window. You can configure the
405 frequency by clicking on the frequency box and selecting the
406 desired frequency. The TeleGPS application remembers the last
407 frequency selected for each TeleDongle and selects that
408 automatically the next time you use that device.
411 Below the TeleDongle frequency selector, the window contains a few
412 significant pieces of information about the altimeter providing
413 the telemetry data stream:
417 <para>The configured call-sign</para>
420 <para>The device serial number</para>
423 <para>The flight number. TeleGPS remembers how many
429 The Received Signal Strength Indicator value. This lets
430 you know how strong a signal TeleDongle is receiving. The
431 radio inside TeleDongle operates down to about -100dBm;
432 weaker signals may not be receivable. The packet link uses
433 error detection and correction techniques which prevent
434 incorrect data from being reported.
439 The age of the displayed data, in seconds since the last
440 successfully received telemetry packet. In normal operation
441 this will stay in the low single digits. If the number starts
442 counting up, then you are no longer receiving data over the radio
443 link from the flight computer.
448 Finally, the largest portion of the window contains a set of
449 tabs, each of which contain some information about the TeleGPS
450 board. The final 'table' tab displays many of the raw telemetry
451 values in one place in a spreadsheet-like format.
456 The Map tab shows the TeleGPS track over time on top of map
457 data making it easy to locate the device.
462 <imagedata fileref="telegps-map.png" width="5.5in"/>
467 The map's default scale is approximately 3m (10ft) per pixel. The map
468 can be dragged using the left mouse button. The map will attempt
469 to keep the rocket roughly centered while data is being received.
472 You can adjust the style of map and the zoom level with
473 buttons on the right side of the map window. You can draw a
474 line on the map by moving the mouse over the map with a
475 button other than the left one pressed, or by pressing the
476 left button while also holding down the shift key. The
477 length of the line in real-world units will be shown at the
481 Images are fetched automatically via the Google Maps Static API,
482 and cached on disk for reuse. If map images cannot be downloaded,
483 the rocket's path will be traced on a dark gray background
487 You can pre-load images for your favorite launch sites
488 before you leave home; check out the 'Preload Maps' section below.
492 <title>Location</title>
494 The Location tab shows the raw GPS data received from TeleGPS.
499 <imagedata fileref="telegps-location.png" width="5.5in"/>
505 <title>Status</title>
507 The Status tab shows data relative to the location of
508 TeleGPS when the application first received telemetry from
514 <imagedata fileref="telegps-status.png" width="5.5in"/>
522 The Table tab shows detailed information about the GPS
528 <imagedata fileref="telegps-table.png" width="5.5in"/>
546 <title>TeleGPS Menus</title>
548 TeleGPS has three or four menus at the top of the window:
554 New Window, Graph Data, Export Data, Load Maps, Preferences, Close and Exit
562 Connect Device, Disconnect and Scan Channels
570 Download Data, Configure Device and Flash Device
575 <term>Frequency</term>
578 This shows the current monitoring frequency with a
579 drop-down menu listing other configured
580 frequencies. You can change the set of frequencies
581 shown here from the Preferences dialog. This menu is
582 only shown when the TeleGPS application is connected
583 to a TeleDongle or TeleBT device.
590 <title>New Window</title>
592 This creates another telemetry monitoring window, in case
593 you have multiple TeleDongle devices connected to the
598 <title>Graph Data</title>
600 This brings up a file dialog to load a saved log, either
601 a .telem file of recorded telemetry or .eeprom of saved
602 data from on-board memory. It looks a bit like the flight
603 monitoring window, using a selection of tabs to show
604 different views of the saved data.
609 The Graph tab shows a plot of the the GPS data
610 collected. The X axis is time in seconds; there are a
611 variety of Y axes available for different kinds of data.
616 <imagedata fileref="telegps-graph-graph.png" width="6in" scalefit="1"/>
622 <title>Configure Graph</title>
626 <imagedata fileref="telegps-graph-configure.png" width="6in" scalefit="1"/>
631 This selects which graph elements to show, and, at the
632 bottom, lets you switch between metric and imperial units
636 <title>Statistics</title>
640 <imagedata fileref="telegps-graph-stats.png" width="6in" scalefit="1"/>
645 Shows overall data computed from the flight.
653 <imagedata fileref="telegps-graph-map.png" width="6in" scalefit="1"/>
658 Shows a map of the area overlaid with the GPS track. As with
659 the telemetry monitoring window, you can select the style
660 of map and zoom level using buttons along the side;
661 you can scroll the map by dragging within the map pressing
662 the left button and you can draw a line to measure
663 distances using either the left button with the shift key,
669 <title>Export Data</title>
671 This tool takes the raw data files and makes them available for
672 external analysis. When you select this button, you are prompted to
673 select a data file, which can be either a .eeprom or .telem.
674 The .eeprom files contain higher resolution and more continuous data,
675 while .telem files contain receiver signal strength information.
676 Next, a second dialog appears which is used to select
677 where to write the resulting file. It has a selector to choose
678 between CSV and KML file formats.
681 <title>Comma Separated Value Format</title>
683 This is a text file containing the data in a form suitable for
684 import into a spreadsheet or other external data analysis
685 tool. The first few lines of the file contain the version and
686 configuration information from TeleGPS, then
687 there is a single header line which labels all of the
688 fields. All of these lines start with a '#' character which
689 many tools can be configured to skip over.
692 The remaining lines of the file contain the data, with each
693 field separated by a comma and at least one space. All of
694 the sensor values are converted to standard units, with the
695 barometric data reported in both pressure, altitude and
696 height above pad units.
700 <title>Keyhole Markup Language (for Google Earth)</title>
702 This is the format used by Google Earth to provide an overlay
703 within that application. With this, you can use Google Earth to
704 see the whole flight path in 3D.
709 <title>Load Maps</title>
713 <imagedata fileref="load-maps.png" width="5.2in" scalefit="1"/>
718 Before using TeleGPS, you can use Load Maps to load map data
719 in case you don't have access to the internet while
723 There's a drop-down menu of rocket launch sites we know
724 about; if your favorites aren't there, please let us know
725 the lat/lon and name of the site. The contents of this list
726 are actually downloaded from our server at run-time, so as
727 new sites are sent in, they'll get automatically added to
728 this list. If the launch site isn't in the list, you can
729 manually enter the lat/lon values
732 There are four different kinds of maps you can view; you can
733 select which to download by selecting as many as you like from
740 A combination of satellite imagery and road data. This
746 <term>Satellite</term>
749 Just the satellite imagery without any annotation.
757 Roads, political boundaries and a few geographic features.
765 Contour intervals and shading that show hills and
773 You can specify the range of zoom levels to download; smaller
774 numbers show more area with less resolution. The default
775 level, 0, shows about 3m/pixel. One zoom level change
776 doubles or halves that number.
779 The Tile Radius value sets how large an area around the center
780 point to download. Each tile is 512x512 pixels, and the
781 'radius' value specifies how many tiles away from the center
782 will be downloaded. Specify a radius of 0 and you get only the
783 center tile. A radius of 1 loads a 3x3 grid, centered on the
787 Clicking the 'Load Map' button will fetch images from Google
788 Maps; note that Google limits how many images you can fetch at
789 once, so if you load more than one launch site, you may get
790 some gray areas in the map which indicate that Google is tired
791 of sending data to you. Try again later.
795 <title>Preferences</title>
799 <imagedata fileref="telegps-preferences.png" width="2.4in" scalefit="1"/>
804 <title>Voice Settings</title>
806 AltosUI provides voice announcements during flight so that you
807 can keep your eyes on the sky and still get information about
808 the current flight status. However, sometimes you don't want
815 <para>Turns all voice announcements on and off</para>
819 <term>Test Voice</term>
822 Plays a short message allowing you to verify
823 that the audio system is working and the volume settings
831 <title>Log Directory</title>
833 AltosUI logs all telemetry data and saves all TeleMetrum flash
834 data to this directory. This directory is also used as the
835 staring point when selecting data files for display or export.
838 Click on the directory name to bring up a directory choosing
839 dialog, select a new directory and click 'Select Directory' to
840 change where AltosUI reads and writes data files.
844 <title>Callsign</title>
846 This value is transmitted in each command packet sent from
847 TeleDongle and received from an altimeter. It is not used in
848 telemetry mode, as the callsign configured in the altimeter board
849 is included in all telemetry packets. Configure this
850 with the AltosUI operators call sign as needed to comply with
851 your local radio regulations.
854 Note that to successfully command a flight computer over the radio
855 (to configure the altimeter, monitor idle, or fire pyro charges),
856 the callsign configured here must exactly match the callsign
857 configured in the flight computer. This matching is case
862 <title>Imperial Units</title>
864 This switches between metric units (meters) and imperial
865 units (feet and miles). This affects the display of values
866 use during flight monitoring, configuration, data graphing
867 and all of the voice announcements. It does not change the
868 units used when exporting to CSV files, those are always
869 produced in metric units.
873 <title>Serial Debug</title>
875 This causes all communication with a connected device to be
876 dumped to the console from which AltosUI was started. If
877 you've started it from an icon or menu entry, the output
878 will simply be discarded. This mode can be useful to debug
879 various serial communication issues.
883 <title>Font Size</title>
885 Selects the set of fonts used in the flight monitor
886 window. Choose between the small, medium and large sets.
890 <title>Look & Feel</title>
892 Adjust the style of the windows. By default, the TeleGPS
893 application attempts to blend in with the native style.
897 <title>Manage Frequencies</title>
899 This brings up a dialog where you can configure the set of
900 frequencies shown in the various frequency menus. You can
901 add as many as you like, or even reconfigure the default
902 set. Changing this list does not affect the frequency
903 settings of any devices, it only changes the set of
904 frequencies shown in the menus.
911 This closes the current window, leaving any other windows
912 open and the application running.
918 This closes all TeleGPS windows and terminates the application.
922 <title>Connect Device</title>
924 Selecting this item brings up a dialog box listing all of
925 the connected TeleDongle devices. When you choose one of
926 these, AltosUI will display telemetry data as received by
927 the selected TeleDongle device.
932 <imagedata fileref="device-selection.png" width="3.1in"/>
938 <title>Disconnect</title>
940 Disconnects the currently connected TeleDongle or TeleBT
944 <title>Scan Channels</title>
946 Scans the configured set of frequencies looking for
947 telemetry signals. A list of all of the discovered signals
948 is show; selecting one of those and clicking on 'Monitor'
949 will select that frequency in the associated TeleGPS
955 <imagedata fileref="telegps-scan.png" width="3.1in"/>
961 <title>Download Data</title>
963 TeleGPS records data to its internal flash memory.
964 On-board data is recorded at the same rate as telemetry
965 but is not subject to radio drop-outs. As
966 such, it generally provides a more complete and precise record.
967 The 'Download Data' menu entry allows you to read the
968 flash memory and write it to disk.
971 Select the 'Download Data' menu entry to bring up a list of
972 connected TeleGPS devices. After the device has been
973 selected, a dialog showing the data stored in the
974 device will be shown allowing you to select which entries to
975 download and which to delete. You must erase flights in order for the space they
976 consume to be reused by another track. This prevents
977 accidentally losing data if you neglect to download
978 data before starting TeleGPS again. Note that if there is no more
979 space available in the device, then no data will be recorded.
982 The file name for each data log is computed automatically
983 from the recorded date, altimeter serial number and flight
988 <title>Configure Device</title>
992 <imagedata fileref="telegps-configure.png" width="3.6in" scalefit="1"/>
997 Select this button and then select any connected TeleGPS
998 device from the list provided.
1001 The first few lines of the dialog provide information about the
1002 connected device, including the product name,
1003 software version and hardware serial number. Below that are the
1004 individual configuration entries.
1007 At the bottom of the dialog, there are four buttons:
1014 This writes any changes to the
1015 configuration parameter block in flash memory. If you don't
1016 press this button, any changes you make will be lost.
1024 This resets the dialog to the most recently saved values,
1025 erasing any changes you have made.
1033 This reboots the device. This will restart logging for
1034 a new flight number, if any log information has been
1035 saved for the current flight.
1043 This closes the dialog. Any unsaved changes will be
1050 The rest of the dialog contains the parameters to be configured.
1053 <title>Frequency</title>
1055 This configures which of the frequencies to use for both
1056 telemetry and packet command mode. Note that if you set this
1057 value via packet command mode, the TeleDongle frequency will
1058 also be automatically reconfigured to match so that
1059 communication will continue afterwards.
1063 <title>RF Calibration</title>
1065 The radios in every Altus Metrum device are calibrated at the
1066 factory to ensure that they transmit and receive on the
1067 specified frequency. If you need to you can adjust the calibration
1068 by changing this value. Do not do this without understanding what
1069 the value means, read the appendix on calibration and/or the source
1070 code for more information. To change a TeleDongle's calibration,
1071 you must reprogram the unit completely.
1075 <title>Telemetry/RDF/APRS Enable</title>
1077 Enables the radio for transmission during flight. When
1078 disabled, the radio will not transmit anything during flight
1083 <title>APRS Interval</title>
1085 How often to transmit GPS information via APRS (in
1086 seconds). When set to zero, APRS transmission is
1087 disabled. This option is available on TeleMetrum v2 and
1088 TeleMega boards. TeleMetrum v1 boards cannot transmit APRS
1089 packets. Note that a single APRS packet takes nearly a full
1090 second to transmit, so enabling this option will prevent
1091 sending any other telemetry during that time.
1095 <title>Callsign</title>
1097 This sets the call sign included in each telemetry packet. Set this
1098 as needed to conform to your local radio regulations.
1102 <title>Maximum Log Size</title>
1104 This sets the space (in kilobytes) allocated for each data
1105 log. The available space will be divided into chunks of this
1106 size. A smaller value will allow more logs to be stored,
1107 a larger value will record data for longer times.
1111 <title>Logging Trigger Motion</title>
1113 If TeleGPS moves less than this distance over a long period
1114 of time, it will not log that location, saving storage space.
1118 <title>Position Reporting Interval</title>
1120 This sets how often TeleGPS reports position information via
1121 telemetry and to the on-board log. Reducing this value will
1122 save power and logging memory consumption.
1127 <title>Flash Device</title>
1129 This reprograms TeleGPS devices with new firmware. Please
1130 read the directions for flashing devices in the Updating
1131 Device Firmware chapter below.
1137 <title>Updating Device Firmware</title>
1139 TeleGPS is programmed directly over its USB connectors.
1142 You may wish to begin by ensuring you have current firmware images.
1143 These are distributed as part of the TeleGPS software bundle that
1144 also includes the TeleGPS ground station program. Newer ground
1145 station versions typically work fine with older firmware versions,
1146 so you don't need to update your devices just to try out new
1147 software features. You can always download the most recent
1148 version from <ulink url="http://www.altusmetrum.org/AltOS/"/>.
1152 Updating TeleGPS Firmware
1154 <orderedlist inheritnum='inherit' numeration='arabic'>
1157 Attach a battery and power switch to the target
1158 device. Power up the device.
1163 Using a Micro USB cable, connect the target device to your
1164 computer's USB socket.
1169 Run TeleGPS, and select 'Flash Device' from the Device menu.
1174 Select the target device in the Device Selection dialog.
1179 Select the image you want to flash to the device, which
1180 should have a name in the form
1181 <product>-v<product-version>-<software-version>.ihx, such
1182 as TeleGPS-v1.0-1.4.0.ihx.
1187 Make sure the configuration parameters are reasonable
1188 looking. If the serial number and/or RF configuration
1189 values aren't right, you'll need to change them.
1194 Hit the 'OK' button and the software should proceed to flash
1195 the device with new firmware, showing a progress bar.
1200 Verify that the device is working by using the 'Configure
1201 Altimeter' item to check over the configuration.
1207 <title>Recovering From Self-Flashing Failure</title>
1209 If the firmware loading fails, it can leave the device
1210 unable to boot. Not to worry, you can force the device to
1211 start the boot loader instead, which will let you try to
1212 flash the device again.
1215 On each device, connecting two pins from one of the exposed
1216 connectors will force the boot loader to start, even if the
1217 regular operating system has been corrupted in some way.
1221 <term>TeleMega</term>
1224 Connect pin 6 and pin 1 of the companion connector. Pin 1
1225 can be identified by the square pad around it, and then
1226 the pins could sequentially across the board. Be very
1227 careful to <emphasis>not</emphasis> short pin 8 to
1228 anything as that is connected directly to the battery. Pin
1229 7 carries 3.3V and the board will crash if that is
1230 connected to pin 1, but shouldn't damage the board.
1235 <term>TeleMetrum v2</term>
1238 Connect pin 6 and pin 1 of the companion connector. Pin 1
1239 can be identified by the square pad around it, and then
1240 the pins could sequentially across the board. Be very
1241 careful to <emphasis>not</emphasis> short pin 8 to
1242 anything as that is connected directly to the battery. Pin
1243 7 carries 3.3V and the board will crash if that is
1244 connected to pin 1, but shouldn't damage the board.
1249 <term>EasyMini</term>
1252 Connect pin 6 and pin 1 of the debug connector, which is
1253 the six holes next to the beeper. Pin 1 can be identified
1254 by the square pad around it, and then the pins could
1255 sequentially across the board, making Pin 6 the one on the
1256 other end of the row.
1266 <title>Technical Information</title>
1268 <title>GPS Receiver</title>
1270 TeleGPS uses the u-Blox Max-7Q GPS receiver.
1274 <title>Micro-controller</title>
1276 TeleGPS uses an NXP LPC11U14 micro-controller. This tiny
1277 CPU contains 32kB of flash for the application and 4kB of RAM for
1278 temporary data storage.
1282 <title>Lithium Polymer Battery</title>
1284 Shipping restrictions may prevent us from including a battery
1285 battery with TeleGPS.
1289 <title>Mechanical Considerations</title>
1291 TeleGPS is designed to be rugged enough for typical rocketry
1292 applications. The 4 mounting holes on the board are sized for
1293 use with 4-40 or M3 screws.
1297 <title>On-board data storage</title>
1299 TeleGPS has 2MB of non-volatile storage, separate from the
1300 code storage memory. The TeleGPS firmware uses this to log
1301 information during flight.
1306 <title>Release Notes</title>
1308 <title>Version 1.41</title>
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1311 href="release-notes-1.4.1.xsl"
1312 xpointer="xpointer(/article/*)"/>
1315 <title>Version 1.4</title>
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1318 href="release-notes-1.4.xsl"
1319 xpointer="xpointer(/article/*)"/>
1323 <!-- LocalWords: Altusmetrum TeleGPS