# TeleMetrum
This is a recording dual-deploy altimeter for high power model rocketry
with integrated telemetry link.
## Motivation ##
Bdale and Keith both own
[BeeLine](http://www.bigredbee.com/BeeLine.htm)
trackers from
[Big Red Bee](http://www.bigredbee.com), and are pretty happy with them.
They use a PIC processor and a TI CC1050 transmitter chip, and
operate in the ham radio 70cm band.
One weekend while attending a conference together, we got to wondering if
we couldn't adapt one to use as a downlink for the
[AltusMetrum](../AltusMetrum/) altimeter board in addition to direction
finding after flight. That caused us to start thinking about other things
in the design we might want to tweak, and before long we were working on the
design of a new tracker board derived from the BeeLine design.
Another friend at the same conference showed us a board he was working on
using a different part in the same TI series, that integrated a transceiver
and CPU on the same chip.
It didn't take us long to realize that with such a part we could combine and
simplify things by building a new altimeter with integrated RF link!
## Features ##
### User View ###
* Recording altimeter for model rocketry
* Supports dual deployment (can fire 2 ejection charges)
* 70cm ham-band transceiver for telemetry downlink
* Primary operations based on pressure sensor
* Temperature sensor
* 1-axis high-g accelerometer for motor characterization
* On-board non-volatile memory for flight data storage
* Serial port for attachment of GPS module
* USB for power, configuration, and data recovery
* Integrated support for LiPo rechargeable batteries
* Designed to fit 29mm airframe coupler tube
### Developer View ###
* [TI CC1111F32](http://focus.ti.com/docs/prod/folders/print/cc1111f32.html) Low Power RF System-on-Chip
* Sub-1Ghz transceiver
* 8051 MCU
* 32k Flash
* 4k RAM
* USB 2.0
* analog, digital, and serial I/O
* [Microchip 25LC1024](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en520389) CMOS serial EEPROM
* 128k x 8
* SPI interface
* Various Sensors
* [Freescale MP3H6115A](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MP3H6115A6U) pressure sensor
* [Freescale MMA2202EG](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MMA2202EG) 50g accelerometer. Can use 40-200g variants!
* [Microchip MCP9700A](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en027103) temperature sensor
* Software Features (planned)
* Written mostly in C with some 8051 assembler
* Runs from on-chip flash, uses on-chip RAM, stores flight data to
serial EEPROM chip
* USB serial emulation for "console" interface
* USB mass storage emulation for data recovery
* Tools Used
* [gEDA](http://geda.seul.org/) for schematic capture and PCB layout
* [SDCC](http://sdcc.sourceforge.net/) compiler and source debugger
* [FreeRTOS](http://www.freertos.org/) kernel
* Licenses
* The hardware is licensed under the TAPR [Open Hardware License](http://www.tapr.org/ohl.html)
* The software is licensed [GPL version 2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html)
## Problems ##
* The CC1111F32 is a 36-pin QFN package, which necessitates reflow soldering.
* Since we needed to reflow solder anyway, and because TI used them in their
reference design, we went a little crazy and used 0402 passive parts
everywhere. That means working under a microscope to place parts!
## Artifacts ##
The hardware design current gEDA files are available from
[git.gag.com](http://git.gag.com).
As of 6 January 2009, the raw boards are here, so we're nearly ready to try
building our first prototype! Stay tuned for updates, and note that
Bdale will be giving an update in his session at Linux Conference Australia
in late January...
## Motivation ##
Bdale and Keith both own
[BeeLine](http://www.bigredbee.com/BeeLine.htm)
trackers from
[Big Red Bee](http://www.bigredbee.com), and are pretty happy with them.
They use a PIC processor and a TI CC1050 transmitter chip, and
operate in the ham radio 70cm band.
One weekend while attending a conference together, we got to wondering if
we couldn't adapt one to use as a downlink for the
[AltusMetrum](../AltusMetrum/) altimeter board in addition to direction
finding after flight. That caused us to start thinking about other things
in the design we might want to tweak, and before long we were working on the
design of a new tracker board derived from the BeeLine design.
Another friend at the same conference showed us a board he was working on
using a different part in the same TI series, that integrated a transceiver
and CPU on the same chip.
It didn't take us long to realize that with such a part we could combine and
simplify things by building a new altimeter with integrated RF link!
## Features ##
### User View ###
* Recording altimeter for model rocketry
* Supports dual deployment (can fire 2 ejection charges)
* 70cm ham-band transceiver for telemetry downlink
* Primary operations based on pressure sensor
* Temperature sensor
* 1-axis high-g accelerometer for motor characterization
* On-board non-volatile memory for flight data storage
* Serial port for attachment of GPS module
* USB for power, configuration, and data recovery
* Integrated support for LiPo rechargeable batteries
* Designed to fit 29mm airframe coupler tube
### Developer View ###
* [TI CC1111F32](http://focus.ti.com/docs/prod/folders/print/cc1111f32.html) Low Power RF System-on-Chip
* Sub-1Ghz transceiver
* 8051 MCU
* 32k Flash
* 4k RAM
* USB 2.0
* analog, digital, and serial I/O
* [Microchip 25LC1024](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en520389) CMOS serial EEPROM
* 128k x 8
* SPI interface
* Various Sensors
* [Freescale MP3H6115A](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MP3H6115A6U) pressure sensor
* [Freescale MMA2202EG](http://www.freescale.com/webapp/search.partparamdetail.framework?PART_NUMBER=MMA2202EG) 50g accelerometer. Can use 40-200g variants!
* [Microchip MCP9700A](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en027103) temperature sensor
* Software Features (planned)
* Written mostly in C with some 8051 assembler
* Runs from on-chip flash, uses on-chip RAM, stores flight data to
serial EEPROM chip
* USB serial emulation for "console" interface
* USB mass storage emulation for data recovery
* Tools Used
* [gEDA](http://geda.seul.org/) for schematic capture and PCB layout
* [SDCC](http://sdcc.sourceforge.net/) compiler and source debugger
* [FreeRTOS](http://www.freertos.org/) kernel
* Licenses
* The hardware is licensed under the TAPR [Open Hardware License](http://www.tapr.org/ohl.html)
* The software is licensed [GPL version 2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html)
## Problems ##
* The CC1111F32 is a 36-pin QFN package, which necessitates reflow soldering.
* Since we needed to reflow solder anyway, and because TI used them in their
reference design, we went a little crazy and used 0402 passive parts
everywhere. That means working under a microscope to place parts!
## Artifacts ##
The hardware design current gEDA files are available from
[git.gag.com](http://git.gag.com).
As of 6 January 2009, the raw boards are here, so we're nearly ready to try
building our first prototype! Stay tuned for updates, and note that
Bdale will be giving an update in his session at Linux Conference Australia
in late January...