or radio link via TeleDongle.
</para>
<section>
- <title>Radio Frequencies</title>
+ <title>Radio Frequency</title>
<para>
Altus Metrum boards support radio frequencies in the 70cm
band. By default, the configuration interface provides a
altimeter and TeleDongle must be configured to the same
frequency to successfully communicate with each other.
</para>
- <para>
- To set the radio frequency, use the 'c R' command to specify the
- radio transceiver configuration parameter. This parameter is computed
- using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
- the standard calibration reference frequency, 'S', (normally 434.550MHz):
- <programlisting>
- R = F / S * C
- </programlisting>
- Round the result to the nearest integer value.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board flash on
- your altimeter board if you want the change to stay in place across reboots.
- </para>
</section>
<section>
<title>Apogee Delay</title>
primary and backup pyrotechnic charges do not fire simultaneously.
</para>
<para>
- To set the apogee delay, use the 'c d' command.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip.
- </para>
- <para>
- Please note that the Altus Metrum apogee detection algorithm
- fires exactly at apogee. If you are also flying an
- altimeter like the PerfectFlite MAWD, which only supports
- selecting 0 or 1 seconds of apogee delay, you may wish to
- set the MAWD to 0 seconds delay and set the TeleMetrum to
- fire your backup 2 or 3 seconds later to avoid any chance of
- both charges firing simultaneously. We've flown several
- air-frames this way quite happily, including Keith's
- successful L3 cert.
+ The Altus Metrum apogee detection algorithm fires exactly at
+ apogee. If you are also flying an altimeter like the
+ PerfectFlite MAWD, which only supports selecting 0 or 1
+ seconds of apogee delay, you may wish to set the MAWD to 0
+ seconds delay and set the TeleMetrum to fire your backup 2
+ or 3 seconds later to avoid any chance of both charges
+ firing simultaneously. We've flown several air-frames this
+ way quite happily, including Keith's successful L3 cert.
</para>
</section>
<section>
than the primary so that both pyrotechnic charges don't fire
simultaneously.
</para>
- <para>
- To set the main deployment altitude, use the 'c m' command.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip.
- </para>
</section>
- </section>
- <section>
- <title>Calibration</title>
- <para>
- There are only two calibrations required for a TeleMetrum board, and
- only one for TeleDongle and TeleMini.
- </para>
<section>
- <title>Radio Frequency</title>
- <para>
- The radio frequency is synthesized from a clock based on the 48 MHz
- crystal on the board. The actual frequency of this oscillator must be
- measured to generate a calibration constant. While our GFSK modulation
- bandwidth is wide enough to allow boards to communicate even when
- their oscillators are not on exactly the same frequency, performance
- is best when they are closely matched.
- Radio frequency calibration requires a calibrated frequency counter.
- Fortunately, once set, the variation in frequency due to aging and
- temperature changes is small enough that re-calibration by customers
- should generally not be required.
- </para>
- <para>
- To calibrate the radio frequency, connect the UHF antenna port to a
- frequency counter, set the board to 434.550MHz, and use the 'C'
- command to generate a CW carrier. Wait for the transmitter temperature
- to stabilize and the frequency to settle down.
- Then, divide 434.550 MHz by the
- measured frequency and multiply by the current radio cal value show
- in the 'c s' command. For an unprogrammed board, the default value
- is 1186611. Take the resulting integer and program it using the 'c f'
- command. Testing with the 'C' command again should show a carrier
- within a few tens of Hertz of the intended frequency.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip.
- </para>
+ <title>Maximum Flight Log</title>
<para>
- when the radio calibration value is changed, the radio
- frequency value is reset to the same value, so you'll need
- to recompute and reset the radio frequency value using the
- new radio calibration value.
+ TeleMetrum version 1.1 has 2MB of on-board flash storage,
+ enough to hold over 40 minutes of data at full data rate
+ (100 samples/second). TeleMetrum 1.0 has 1MB of on-board
+ storage. As data are stored at a reduced rate during
+ descent, there's plenty of space to store many flights worth
+ of data.
+ </para>
+ <para>
+ The on-board flash is partitioned into separate flight logs,
+ each of a fixed maximum size. Increase the maximum size of
+ each log and you reduce the number of flights that can be
+ stored. Decrease the size and TeleMetrum can store more
+ flights.
+ </para>
+ <para>
+ All of the configuration data is also stored in the flash
+ memory, which consumes 64kB on TeleMetrum v1.1 and 256B on
+ TeleMetrum v1.0. This configuration space is not available
+ for storing flight log data.
+ </para>
+ <para>
+ To compute the amount of space needed for a single flight,
+ you can multiply the expected ascent time (in seconds) by
+ 800, multiply the expected descent time (in seconds) by 80
+ and add the two together. That will slightly under-estimate
+ the storage (in bytes) needed for the flight. For instance,
+ a flight spending 20 seconds in ascent and 150 seconds in
+ descent will take about (20 * 800) + (150 * 80) = 28000
+ bytes of storage. You could store dozens of these flights in
+ the on-board flash.
+ </para>
+ <para>
+ The default size, 192kB, allows for 10 flights of storage on
+ TeleMetrum v1.1 and 5 flights on TeleMetrum v1.0. This
+ ensures that you won't need to erase the memory before
+ flying each time while still allowing more than sufficient
+ storage for each flight.
</para>
</section>
<section>
- <title>TeleMetrum Accelerometer</title>
- <para>
- The TeleMetrum accelerometer we use has its own 5 volt power supply and
- the output must be passed through a resistive voltage divider to match
- the input of our 3.3 volt ADC. This means that unlike the barometric
- sensor, the output of the acceleration sensor is not ratio-metric to
- the ADC converter, and calibration is required. We also support the
- use of any of several accelerometers from a Freescale family that
- includes at least +/- 40g, 50g, 100g, and 200g parts. Using gravity,
- a simple 2-point calibration yields acceptable results capturing both
- the different sensitivities and ranges of the different accelerometer
- parts and any variation in power supply voltages or resistor values
- in the divider network.
- </para>
- <para>
- To calibrate the acceleration sensor, use the 'c a 0' command. You
- will be prompted to orient the board vertically with the UHF antenna
- up and press a key, then to orient the board vertically with the
- UHF antenna down and press a key.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip.
- </para>
- <para>
- The +1g and -1g calibration points are included in each telemetry
- frame and are part of the header extracted by ao-dumplog after flight.
- Note that we always store and return raw ADC samples for each
- sensor... nothing is permanently "lost" or "damaged" if the
- calibration is poor.
- </para>
- <para>
- In the unlikely event an accel cal that goes badly, it is possible
- that TeleMetrum may always come up in 'pad mode' and as such not be
- listening to either the USB or radio link. If that happens,
- there is a special hook in the firmware to force the board back
- in to 'idle mode' so you can re-do the cal. To use this hook, you
- just need to ground the SPI clock pin at power-on. This pin is
- available as pin 2 on the 8-pin companion connector, and pin 1 is
- ground. So either carefully install a fine-gauge wire jumper
- between the two pins closest to the index hole end of the 8-pin
- connector, or plug in the programming cable to the 8-pin connector
- and use a small screwdriver or similar to short the two pins closest
- to the index post on the 4-pin end of the programming cable, and
- power up the board. It should come up in 'idle mode' (two beeps).
- </para>
+ <title>Ignite Mode</title>
+ <para>
+ Instead of firing one charge at apogee and another charge at
+ a fixed height above the ground, you can configure the
+ altimeter to fire both at apogee or both during
+ descent. This was added to support an airframe that has two
+ TeleMetrum computers, one in the fin can and one in the
+ nose.
+ </para>
+ <para>
+ Providing the ability to use both igniters for apogee or
+ main allows some level of redundancy without needing two
+ flight computers. In Redundant Apogee or Redundant Main
+ mode, the two charges will be fired two seconds apart.
+ </para>
</section>
- </section>
- <section>
- <title>Updating Device Firmware</title>
- <para>
- The big conceptual thing to realize is that you have to use a
- TeleDongle as a programmer to update a TeleMetrum or TeleMini,
- and a TeleMetrum or other TeleDongle to program the TeleDongle
- Due to limited memory resources in the cc1111, we don't support
- programming directly over USB.
- </para>
- <para>
- You may wish to begin by ensuring you have current firmware images.
- These are distributed as part of the AltOS software bundle that
- also includes the AltosUI ground station program. Newer ground
- station versions typically work fine with older firmware versions,
- so you don't need to update your devices just to try out new
- software features. You can always download the most recent
- version from <ulink url="http://www.altusmetrum.org/AltOS/"/>.
- </para>
- <para>
- We recommend updating the altimeter first, before updating TeleDongle.
- </para>
- <section>
- <title>Updating TeleMetrum Firmware</title>
- <orderedlist inheritnum='inherit' numeration='arabic'>
- <listitem>
- Find the 'programming cable' that you got as part of the starter
- kit, that has a red 8-pin MicroMaTch connector on one end and a
- red 4-pin MicroMaTch connector on the other end.
- </listitem>
- <listitem>
- Take the 2 screws out of the TeleDongle case to get access
- to the circuit board.
- </listitem>
- <listitem>
- Plug the 8-pin end of the programming cable to the
- matching connector on the TeleDongle, and the 4-pin end to the
- matching connector on the TeleMetrum.
- Note that each MicroMaTch connector has an alignment pin that
- goes through a hole in the PC board when you have the cable
- oriented correctly.
- </listitem>
- <listitem>
- Attach a battery to the TeleMetrum board.
- </listitem>
- <listitem>
- Plug the TeleDongle into your computer's USB port, and power
- up the TeleMetrum.
- </listitem>
- <listitem>
- Run AltosUI, and select 'Flash Image' from the File menu.
- </listitem>
- <listitem>
- Pick the TeleDongle device from the list, identifying it as the
- programming device.
- </listitem>
- <listitem>
- Select the image you want put on the TeleMetrum, which should have a
- name in the form telemetrum-v1.1-1.0.0.ihx. It should be visible
- in the default directory, if not you may have to poke around
- your system to find it.
- </listitem>
- <listitem>
- Make sure the configuration parameters are reasonable
- looking. If the serial number and/or RF configuration
- values aren't right, you'll need to change them.
- </listitem>
- <listitem>
- Hit the 'OK' button and the software should proceed to flash
- the TeleMetrum with new firmware, showing a progress bar.
- </listitem>
- <listitem>
- Confirm that the TeleMetrum board seems to have updated OK, which you
- can do by plugging in to it over USB and using a terminal program
- to connect to the board and issue the 'v' command to check
- the version, etc.
- </listitem>
- <listitem>
- If something goes wrong, give it another try.
- </listitem>
- </orderedlist>
- </section>
- <section>
- <title>Updating TeleMini Firmware</title>
- <orderedlist inheritnum='inherit' numeration='arabic'>
- <listitem>
- You'll need a special 'programming cable' to reprogram the
- TeleMini. It's available on the Altus Metrum web store, or
- you can make your own using an 8-pin MicroMaTch connector on
- one end and a set of four pins on the other.
- </listitem>
- <listitem>
- Take the 2 screws out of the TeleDongle case to get access
- to the circuit board.
- </listitem>
- <listitem>
- Plug the 8-pin end of the programming cable to the matching
- connector on the TeleDongle, and the 4-pins into the holes
- in the TeleMini circuit board. Note that the MicroMaTch
- connector has an alignment pin that goes through a hole in
- the PC board when you have the cable oriented correctly, and
- that pin 1 on the TeleMini board is marked with a square pad
- while the other pins have round pads.
- </listitem>
- <listitem>
- Attach a battery to the TeleMini board.
- </listitem>
- <listitem>
- Plug the TeleDongle into your computer's USB port, and power
- up the TeleMini
- </listitem>
- <listitem>
- Run AltosUI, and select 'Flash Image' from the File menu.
- </listitem>
- <listitem>
- Pick the TeleDongle device from the list, identifying it as the
- programming device.
- </listitem>
- <listitem>
- Select the image you want put on the TeleMini, which should have a
- name in the form telemini-v1.0-1.0.0.ihx. It should be visible
- in the default directory, if not you may have to poke around
- your system to find it.
- </listitem>
- <listitem>
- Make sure the configuration parameters are reasonable
- looking. If the serial number and/or RF configuration
- values aren't right, you'll need to change them.
- </listitem>
- <listitem>
- Hit the 'OK' button and the software should proceed to flash
- the TeleMini with new firmware, showing a progress bar.
- </listitem>
- <listitem>
- Confirm that the TeleMini board seems to have updated OK, which you
- can do by configuring it over the radio link through the TeleDongle, or
- letting it come up in "flight" mode and listening for telemetry.
- </listitem>
- <listitem>
- If something goes wrong, give it another try.
- </listitem>
- </orderedlist>
- </section>
- <section>
- <title>Updating TeleDongle Firmware</title>
- <para>
- Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
- firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
+ <section>
+ <title>Pad Orientation</title>
+ <para>
+ TeleMetrum measures acceleration along the axis of the
+ board. Which way the board is oriented affects the sign of
+ the acceleration value. Instead of trying to guess which way
+ the board is mounted in the air frame, TeleMetrum must be
+ explicitly configured for either Antenna Up or Antenna
+ Down. The default, Antenna Up, expects the end of the
+ TeleMetrum board connected to the 70cm antenna to be nearest
+ the nose of the rocket, with the end containing the screw
+ terminals nearest the tail.
</para>
- <orderedlist inheritnum='inherit' numeration='arabic'>
- <listitem>
- Find the 'programming cable' that you got as part of the starter
- kit, that has a red 8-pin MicroMaTch connector on one end and a
- red 4-pin MicroMaTch connector on the other end.
- </listitem>
- <listitem>
- Find the USB cable that you got as part of the starter kit, and
- plug the "mini" end in to the mating connector on TeleMetrum or TeleDongle.
- </listitem>
- <listitem>
- Take the 2 screws out of the TeleDongle case to get access
- to the circuit board.
- </listitem>
- <listitem>
- Plug the 8-pin end of the programming cable to the
- matching connector on the programmer, and the 4-pin end to the
- matching connector on the TeleDongle.
- Note that each MicroMaTch connector has an alignment pin that
- goes through a hole in the PC board when you have the cable
- oriented correctly.
- </listitem>
- <listitem>
- Attach a battery to the TeleMetrum board if you're using one.
- </listitem>
- <listitem>
- Plug both the programmer and the TeleDongle into your computer's USB
- ports, and power up the programmer.
- </listitem>
- <listitem>
- Run AltosUI, and select 'Flash Image' from the File menu.
- </listitem>
- <listitem>
- Pick the programmer device from the list, identifying it as the
- programming device.
- </listitem>
- <listitem>
- Select the image you want put on the TeleDongle, which should have a
- name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
- in the default directory, if not you may have to poke around
- your system to find it.
- </listitem>
- <listitem>
- Make sure the configuration parameters are reasonable
- looking. If the serial number and/or RF configuration
- values aren't right, you'll need to change them. The TeleDongle
- serial number is on the "bottom" of the circuit board, and can
- usually be read through the translucent blue plastic case without
- needing to remove the board from the case.
- </listitem>
- <listitem>
- Hit the 'OK' button and the software should proceed to flash
- the TeleDongle with new firmware, showing a progress bar.
- </listitem>
- <listitem>
- Confirm that the TeleDongle board seems to have updated OK, which you
- can do by plugging in to it over USB and using a terminal program
- to connect to the board and issue the 'v' command to check
- the version, etc. Once you're happy, remove the programming cable
- and put the cover back on the TeleDongle.
- </listitem>
- <listitem>
- If something goes wrong, give it another try.
- </listitem>
- </orderedlist>
- <para>
- Be careful removing the programming cable from the locking 8-pin
- connector on TeleMetrum. You'll need a fingernail or perhaps a thin
- screwdriver or knife blade to gently pry the locking ears out
- slightly to extract the connector. We used a locking connector on
- TeleMetrum to help ensure that the cabling to companion boards
- used in a rocket don't ever come loose accidentally in flight.
- </para>
+ </section>
</section>
- </section>
</chapter>
<chapter>
<section>
<title>Callsign</title>
<para>
- This value is used in command packet mode and is transmitted
- in each packet sent from TeleDongle and received from
- TeleMetrum. It is not used in telemetry mode as that transmits
- packets only from TeleMetrum to TeleDongle. Configure this
+ This value is transmitted in each command packet sent from
+ TeleDongle and received from an altimeter. It is not used in
+ telemetry mode, as the callsign configured in the altimeter board
+ is included in all telemetry packets. Configure this
with the AltosUI operators call sign as needed to comply with
your local radio regulations.
</para>
This reprograms any Altus Metrum device by using a TeleMetrum
or TeleDongle as a programming dongle. Please read the
directions for flashing devices in the Updating Device
- Firmware section above
+ Firmware chapter below.
</para>
<para>
Once you have the programmer and target devices connected,
</para>
</section>
<section>
- <title>Ground Testing</title>
- <para>
- The most important aspect of any installation is careful
- ground testing. Bringing an air-frame up to the LCO table which
- hasn't been ground tested can lead to delays or ejection
- charges firing on the pad, or, even worse, a recovery system
- failure.
- </para>
+ <title>Ground Testing</title>
+ <para>
+ The most important aspect of any installation is careful
+ ground testing. Bringing an air-frame up to the LCO table which
+ hasn't been ground tested can lead to delays or ejection
+ charges firing on the pad, or, even worse, a recovery system
+ failure.
+ </para>
+ <para>
+ Do a 'full systems' test that includes wiring up all igniters
+ without any BP and turning on all of the electronics in flight
+ mode. This will catch any mistakes in wiring and any residual
+ RFI issues that might accidentally fire igniters at the wrong
+ time. Let the air-frame sit for several minutes, checking for
+ adequate telemetry signal strength and GPS lock.
+ </para>
+ <para>
+ Ground test the ejection charges. Prepare the rocket for
+ flight, loading ejection charges and igniters. Completely
+ assemble the air-frame and then use the 'Fire Igniters'
+ interface through a TeleDongle to command each charge to
+ fire. Make sure the charge is sufficient to robustly separate
+ the air-frame and deploy the recovery system.
+ </para>
+ </section>
+ </chapter>
+ <chapter>
+ <title>Updating Device Firmware</title>
+ <para>
+ The big conceptual thing to realize is that you have to use a
+ TeleDongle as a programmer to update a TeleMetrum or TeleMini,
+ and a TeleMetrum or other TeleDongle to program the TeleDongle
+ Due to limited memory resources in the cc1111, we don't support
+ programming directly over USB.
+ </para>
+ <para>
+ You may wish to begin by ensuring you have current firmware images.
+ These are distributed as part of the AltOS software bundle that
+ also includes the AltosUI ground station program. Newer ground
+ station versions typically work fine with older firmware versions,
+ so you don't need to update your devices just to try out new
+ software features. You can always download the most recent
+ version from <ulink url="http://www.altusmetrum.org/AltOS/"/>.
+ </para>
+ <para>
+ We recommend updating the altimeter first, before updating TeleDongle.
+ </para>
+ <section>
+ <title>Updating TeleMetrum Firmware</title>
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+ Find the 'programming cable' that you got as part of the starter
+ kit, that has a red 8-pin MicroMaTch connector on one end and a
+ red 4-pin MicroMaTch connector on the other end.
+ </listitem>
+ <listitem>
+ Take the 2 screws out of the TeleDongle case to get access
+ to the circuit board.
+ </listitem>
+ <listitem>
+ Plug the 8-pin end of the programming cable to the
+ matching connector on the TeleDongle, and the 4-pin end to the
+ matching connector on the TeleMetrum.
+ Note that each MicroMaTch connector has an alignment pin that
+ goes through a hole in the PC board when you have the cable
+ oriented correctly.
+ </listitem>
+ <listitem>
+ Attach a battery to the TeleMetrum board.
+ </listitem>
+ <listitem>
+ Plug the TeleDongle into your computer's USB port, and power
+ up the TeleMetrum.
+ </listitem>
+ <listitem>
+ Run AltosUI, and select 'Flash Image' from the File menu.
+ </listitem>
+ <listitem>
+ Pick the TeleDongle device from the list, identifying it as the
+ programming device.
+ </listitem>
+ <listitem>
+ Select the image you want put on the TeleMetrum, which should have a
+ name in the form telemetrum-v1.1-1.0.0.ihx. It should be visible
+ in the default directory, if not you may have to poke around
+ your system to find it.
+ </listitem>
+ <listitem>
+ Make sure the configuration parameters are reasonable
+ looking. If the serial number and/or RF configuration
+ values aren't right, you'll need to change them.
+ </listitem>
+ <listitem>
+ Hit the 'OK' button and the software should proceed to flash
+ the TeleMetrum with new firmware, showing a progress bar.
+ </listitem>
+ <listitem>
+ Confirm that the TeleMetrum board seems to have updated OK, which you
+ can do by plugging in to it over USB and using a terminal program
+ to connect to the board and issue the 'v' command to check
+ the version, etc.
+ </listitem>
+ <listitem>
+ If something goes wrong, give it another try.
+ </listitem>
+ </orderedlist>
+ </section>
+ <section>
+ <title>Updating TeleMini Firmware</title>
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+ You'll need a special 'programming cable' to reprogram the
+ TeleMini. It's available on the Altus Metrum web store, or
+ you can make your own using an 8-pin MicroMaTch connector on
+ one end and a set of four pins on the other.
+ </listitem>
+ <listitem>
+ Take the 2 screws out of the TeleDongle case to get access
+ to the circuit board.
+ </listitem>
+ <listitem>
+ Plug the 8-pin end of the programming cable to the matching
+ connector on the TeleDongle, and the 4-pins into the holes
+ in the TeleMini circuit board. Note that the MicroMaTch
+ connector has an alignment pin that goes through a hole in
+ the PC board when you have the cable oriented correctly, and
+ that pin 1 on the TeleMini board is marked with a square pad
+ while the other pins have round pads.
+ </listitem>
+ <listitem>
+ Attach a battery to the TeleMini board.
+ </listitem>
+ <listitem>
+ Plug the TeleDongle into your computer's USB port, and power
+ up the TeleMini
+ </listitem>
+ <listitem>
+ Run AltosUI, and select 'Flash Image' from the File menu.
+ </listitem>
+ <listitem>
+ Pick the TeleDongle device from the list, identifying it as the
+ programming device.
+ </listitem>
+ <listitem>
+ Select the image you want put on the TeleMini, which should have a
+ name in the form telemini-v1.0-1.0.0.ihx. It should be visible
+ in the default directory, if not you may have to poke around
+ your system to find it.
+ </listitem>
+ <listitem>
+ Make sure the configuration parameters are reasonable
+ looking. If the serial number and/or RF configuration
+ values aren't right, you'll need to change them.
+ </listitem>
+ <listitem>
+ Hit the 'OK' button and the software should proceed to flash
+ the TeleMini with new firmware, showing a progress bar.
+ </listitem>
+ <listitem>
+ Confirm that the TeleMini board seems to have updated OK, which you
+ can do by configuring it over the radio link through the TeleDongle, or
+ letting it come up in "flight" mode and listening for telemetry.
+ </listitem>
+ <listitem>
+ If something goes wrong, give it another try.
+ </listitem>
+ </orderedlist>
+ </section>
+ <section>
+ <title>Updating TeleDongle Firmware</title>
<para>
- Do a 'full systems' test that includes wiring up all igniters
- without any BP and turning on all of the electronics in flight
- mode. This will catch any mistakes in wiring and any residual
- RFI issues that might accidentally fire igniters at the wrong
- time. Let the air-frame sit for several minutes, checking for
- adequate telemetry signal strength and GPS lock.
- </para>
+ Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
+ firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
+ </para>
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+ Find the 'programming cable' that you got as part of the starter
+ kit, that has a red 8-pin MicroMaTch connector on one end and a
+ red 4-pin MicroMaTch connector on the other end.
+ </listitem>
+ <listitem>
+ Find the USB cable that you got as part of the starter kit, and
+ plug the "mini" end in to the mating connector on TeleMetrum or TeleDongle.
+ </listitem>
+ <listitem>
+ Take the 2 screws out of the TeleDongle case to get access
+ to the circuit board.
+ </listitem>
+ <listitem>
+ Plug the 8-pin end of the programming cable to the
+ matching connector on the programmer, and the 4-pin end to the
+ matching connector on the TeleDongle.
+ Note that each MicroMaTch connector has an alignment pin that
+ goes through a hole in the PC board when you have the cable
+ oriented correctly.
+ </listitem>
+ <listitem>
+ Attach a battery to the TeleMetrum board if you're using one.
+ </listitem>
+ <listitem>
+ Plug both the programmer and the TeleDongle into your computer's USB
+ ports, and power up the programmer.
+ </listitem>
+ <listitem>
+ Run AltosUI, and select 'Flash Image' from the File menu.
+ </listitem>
+ <listitem>
+ Pick the programmer device from the list, identifying it as the
+ programming device.
+ </listitem>
+ <listitem>
+ Select the image you want put on the TeleDongle, which should have a
+ name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
+ in the default directory, if not you may have to poke around
+ your system to find it.
+ </listitem>
+ <listitem>
+ Make sure the configuration parameters are reasonable
+ looking. If the serial number and/or RF configuration
+ values aren't right, you'll need to change them. The TeleDongle
+ serial number is on the "bottom" of the circuit board, and can
+ usually be read through the translucent blue plastic case without
+ needing to remove the board from the case.
+ </listitem>
+ <listitem>
+ Hit the 'OK' button and the software should proceed to flash
+ the TeleDongle with new firmware, showing a progress bar.
+ </listitem>
+ <listitem>
+ Confirm that the TeleDongle board seems to have updated OK, which you
+ can do by plugging in to it over USB and using a terminal program
+ to connect to the board and issue the 'v' command to check
+ the version, etc. Once you're happy, remove the programming cable
+ and put the cover back on the TeleDongle.
+ </listitem>
+ <listitem>
+ If something goes wrong, give it another try.
+ </listitem>
+ </orderedlist>
<para>
- Ground test the ejection charges. Prepare the rocket for
- flight, loading ejection charges and igniters. Completely
- assemble the air-frame and then use the 'Fire Igniters'
- interface through a TeleDongle to command each charge to
- fire. Make sure the charge is sufficient to robustly separate
- the air-frame and deploy the recovery system.
+ Be careful removing the programming cable from the locking 8-pin
+ connector on TeleMetrum. You'll need a fingernail or perhaps a thin
+ screwdriver or knife blade to gently pry the locking ears out
+ slightly to extract the connector. We used a locking connector on
+ TeleMetrum to help ensure that the cabling to companion boards
+ used in a rocket don't ever come loose accidentally in flight.
</para>
</section>
</chapter>
Verify you can connect and disconnect from the units while in your
terminal program by sending the escape-disconnect mentioned above.
</para>
+ <para>
+ To set the radio frequency, use the 'c R' command to specify the
+ radio transceiver configuration parameter. This parameter is computed
+ using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
+ the standard calibration reference frequency, 'S', (normally 434.550MHz):
+ <programlisting>
+ R = F / S * C
+ </programlisting>
+ Round the result to the nearest integer value.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board flash on
+ your altimeter board if you want the change to stay in place across reboots.
+ </para>
+ <para>
+ To set the apogee delay, use the 'c d' command.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
+ <para>
+ To set the main deployment altitude, use the 'c m' command.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
+ <para>
+ To calibrate the radio frequency, connect the UHF antenna port to a
+ frequency counter, set the board to 434.550MHz, and use the 'C'
+ command to generate a CW carrier. Wait for the transmitter temperature
+ to stabilize and the frequency to settle down.
+ Then, divide 434.550 MHz by the
+ measured frequency and multiply by the current radio cal value show
+ in the 'c s' command. For an unprogrammed board, the default value
+ is 1186611. Take the resulting integer and program it using the 'c f'
+ command. Testing with the 'C' command again should show a carrier
+ within a few tens of Hertz of the intended frequency.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
<para>
Note that the 'reboot' command, which is very useful on the altimeters,
will likely just cause problems with the dongle. The *correct* way
strength providing an indication of the direction from receiver to rocket.
</para>
<para>
- TeleMetrum also provides GPS trekking data, which can further simplify
+ TeleMetrum also provides GPS tracking data, which can further simplify
locating the rocket once it has landed. (The last good GPS data
received before touch-down will be on the data screen of 'ao-view'.)
</para>
once you enable the voice output!
</para>
</appendix>
+ <appendix>
+ <title>Calibration</title>
+ <para>
+ There are only two calibrations required for a TeleMetrum board, and
+ only one for TeleDongle and TeleMini. All boards are shipped from
+ the factory pre-calibrated, but the procedures are documented here
+ in case they are ever needed. Re-calibration is not supported by
+ AltosUI, you must connect to the board with a serial terminal program
+ and interact directly with the on-board command interpreter to effect
+ calibration.
+ </para>
+ <section>
+ <title>Radio Frequency</title>
+ <para>
+ The radio frequency is synthesized from a clock based on the 48 MHz
+ crystal on the board. The actual frequency of this oscillator
+ must be measured to generate a calibration constant. While our
+ GFSK modulation
+ bandwidth is wide enough to allow boards to communicate even when
+ their oscillators are not on exactly the same frequency, performance
+ is best when they are closely matched.
+ Radio frequency calibration requires a calibrated frequency counter.
+ Fortunately, once set, the variation in frequency due to aging and
+ temperature changes is small enough that re-calibration by customers
+ should generally not be required.
+ </para>
+ <para>
+ To calibrate the radio frequency, connect the UHF antenna port to a
+ frequency counter, set the board to 434.550MHz, and use the 'C'
+ command in the on-board command interpreter to generate a CW
+ carrier. For TeleMetrum, this is best done over USB. For TeleMini,
+ note that the only way to escape the 'C' command is via power cycle
+ since the board will no longer be listening for commands once it
+ starts generating a CW carrier.
+ </para>
+ <para>
+ Wait for the transmitter temperature to stabilize and the frequency
+ to settle down. Then, divide 434.550 MHz by the
+ measured frequency and multiply by the current radio cal value show
+ in the 'c s' command. For an unprogrammed board, the default value
+ is 1186611. Take the resulting integer and program it using the 'c f'
+ command. Testing with the 'C' command again should show a carrier
+ within a few tens of Hertz of the intended frequency.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
+ <para>
+ Note that any time you re-do the radio frequency calibration, the
+ radio frequency is reset to the default 434.550 Mhz. If you want
+ to use another frequency, you will have to set that again after
+ calibration is completed.
+ </para>
+ </section>
+ <section>
+ <title>TeleMetrum Accelerometer</title>
+ <para>
+ The TeleMetrum accelerometer we use has its own 5 volt power
+ supply and
+ the output must be passed through a resistive voltage divider to match
+ the input of our 3.3 volt ADC. This means that unlike the barometric
+ sensor, the output of the acceleration sensor is not ratio-metric to
+ the ADC converter, and calibration is required. Explicitly
+ calibrating the accelerometers also allows us to load any device
+ from a Freescale family that includes at least +/- 40g, 50g, 100g,
+ and 200g parts. Using gravity,
+ a simple 2-point calibration yields acceptable results capturing both
+ the different sensitivities and ranges of the different accelerometer
+ parts and any variation in power supply voltages or resistor values
+ in the divider network.
+ </para>
+ <para>
+ To calibrate the acceleration sensor, use the 'c a 0' command. You
+ will be prompted to orient the board vertically with the UHF antenna
+ up and press a key, then to orient the board vertically with the
+ UHF antenna down and press a key. Note that the accuracy of this
+ calibration depends primarily on how perfectly vertical and still
+ the board is held during the cal process. As with all 'c'
+ sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
+ <para>
+ The +1g and -1g calibration points are included in each telemetry
+ frame and are part of the header stored in onboard flash to be
+ downloaded after flight. We always store and return raw ADC
+ samples for each sensor... so nothing is permanently "lost" or
+ "damaged" if the calibration is poor.
+ </para>
+ <para>
+ In the unlikely event an accel cal goes badly, it is possible
+ that TeleMetrum may always come up in 'pad mode' and as such not be
+ listening to either the USB or radio link. If that happens,
+ there is a special hook in the firmware to force the board back
+ in to 'idle mode' so you can re-do the cal. To use this hook, you
+ just need to ground the SPI clock pin at power-on. This pin is
+ available as pin 2 on the 8-pin companion connector, and pin 1 is
+ ground. So either carefully install a fine-gauge wire jumper
+ between the two pins closest to the index hole end of the 8-pin
+ connector, or plug in the programming cable to the 8-pin connector
+ and use a small screwdriver or similar to short the two pins closest
+ to the index post on the 4-pin end of the programming cable, and
+ power up the board. It should come up in 'idle mode' (two beeps),
+ allowing a re-cal.
+ </para>
+ </section>
+ </appendix>
<appendix
xmlns:xi="http://www.w3.org/2001/XInclude">
<title>Release Notes</title>
projects / fw / altos / blobdiff