# TeleMetrum
This is a recording dual-deploy altimeter for high power model rocketry
-with integrated telemetry link.
+with integrated GPS and telemetry link.
+
+These are photos of our current version,
+which includes an integrated GPS receiver and patch antenna:
+
+<a href="v0.2/cimg5164-cropped.jpg"> <img src="v0.2/cimg5164-thumb.jpg"></a>
+<a href="v0.2/cimg5171-cropped.jpg"> <img src="v0.2/cimg5171-thumb.jpg"></a>
+
+And this is a photo of our original board with serial port for off-board GPS,
+without the big off-board 1000uF cap from the original ejection circuit:
+
+<a href="v0.1/loadedpair.jpg"> <img src="v0.1/loadedpair-thumb.jpg"></a>
## Motivation ##
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!
-
-<a href="hpim1256.jpg"> <img src="hpim1256-thumb.jpg"></a>
-<a href="hpim1257.jpg"> <img src="hpim1257-thumb.jpg"></a>
+simplify things by building a new altimeter with integrated RF link! And
+after gaining some experience in 2009 with a first version, we realized we
+always want GPS on board, which lead to our current second generation boards.
## Features ##
* 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
+* Barometric pressure sensor good to 45k feet MSL
* 1-axis high-g accelerometer for motor characterization
+* on-board GPS
* 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 tube
+* Uses LiPo to fire e-matches, optional support for separate pyro battery
+* 2.75 x 1 inch board designed to fit inside 29mm airframe coupler tube
### Developer View ###
-* TI CC1111F32 Low Power RF System-on-Chip
+* [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 CMOS serial EEPROM
- * 128k x 8
+ * 6 12-bit analog inputs (11 bits with single-ended sensors)
+ * 2 channels of serial I/O
+ * digital I/O
+* [Atmel AT45DB081D](http://www.atmel.com/dyn/products/product_card.asp?part_id=3819) DataFlash memory
+ * 1M x 8
+ * 256 byte page size
* SPI interface
-* Various Sensors
- * Freescale MP3H6115A pressure sensor
- * Freescale MMA2202EG 50g accelerometer. Can use 40-200g variants!
- * Microchip MCP9700A temperature sensor
-* Software Features (planned)
+ * other parts in this Atmel DataFlash series can optionally be used
+* [SkyTraq](http://www.skytraq.com.tw/) Venus634FLPx GPS receiver
+ * on-board passive patch antenna
+ * U.FL connector with 3.3V DC for optional external amplified antenna
+* [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!
+* Software Features
* Written mostly in C with some 8051 assembler
* Runs from on-chip flash, uses on-chip RAM, stores flight data to
- serial EEPROM chip
+ serial DataFlash chip
* USB serial emulation for "console" interface
- * USB mass storate emulation for data recovery
* Tools Used
- * [gEDA](http://geda.seul.org/) for schematic capture and PCB layout
- * [SDCC](http://sdcc.sourceforge.net/) compiler
- * [FreeRTOS](http://www.freertos.org/) kernel
+ * [gEDA](http://www.gpleda.org/) for schematic capture and PCB layout
+ * [SDCC](http://sdcc.sourceforge.net/) compiler and source debugger
* Licenses
- * The hardware is licensed under the TAPR OHL
- * The software is licensed GPL version 2
+ * The hardware is licensed under the [TAPR](http://www.tapr.org) [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 ##
+### v0.1 Differences ###
-* The CC1111F32 is a 36-pin QFN package, which necessitates reflow soldering.
+* 2.5 x 1 inch board with all parts mounted on one side
+* 4-pin PicoBlade serial port connector for attachment of external GPS module
+* USB connector projected approximately 3mm over the edge of the board
+* Debug connector used 4 IC socket pins on 100 mil centers
+* no companion board interface
+* [Microchip 25LC1024](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en520389) CMOS serial EEPROM instead of DataFlash
+ * 128k x 8
+ * SPI interface
+* [Microchip MCP9700A](http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en027103) temperature sensor instead of using cc1111 on-chip sensor
+* used 1000uF electrolytic capacitor charged to 5V for pyro charges
-* 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!
+## [Production History](production) ##
-## Artifacts ##
+## [Flight Logs](flightlogs) ##
-The hardware design current gEDA files are available from
-[git.gag.com](http://git.gag.com).
+## Problems ##
-As of 1 January 2009, the parts and stencil for v0.1 have arrived, and
-we're waiting for the raw PC boards! Stay tuned for updates, and note that
-Bdale will be giving an update in his session at Linux Conference Australia
-in late January...
+* 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! Without an inspection microscope, loading and testing these
+ boards might be impossible.
+
+* The v0.1 artwork has the USB connector footprint placed wrong, so that the
+ connector hangs out over the edge of the board instead of being flush with
+ the edge.
+
+* The v0.1 artwork has two issues that require cuts and jumps. The first is
+ that we need chip select on the SPI memory. To fix that, we give up the
+ ability to put the accelerometer into self-test mode and use that GPIO line
+ to pull chip select on the memory. The second is that the igniter sense
+ circuits each need a second resistor to complete the voltage divider so our
+ 3.3V CPU ADC can read the 5V ejection voltage. This is fixed by changing
+ two resistor values, and tacking two additional resistors onto the board
+ with jumpers to ground.
+## Artifacts ##
+
+The hardware design current gEDA files are available from
+[git.gag.com](http://git.gag.com) in the project
+[hw/telemetrum](http://git.gag.com/?p=hw/telemetrum;a=summary).
+
+Work on the next version proceeds on the master branch, with occasional
+temporary branches created when Bdale is making some major / speculative
+change. The 'v0.2' and 'v0.1' branches document what we're actually flying
+right now on the two respective PCB revisions. The 'ground' branch has a
+cut-down schematic used to generate the BOM for partially loading v0.1 boards
+to used on the ground. We call the on-the-ground version 'TeleDongle'.
+
+For those who don't have ready access to the gEDA suite, here are pdf snapshots
+of files in more easily readable form.
+
+* These are from the v0.2 branch:
+ * [schematic](v0.2/telemetrum.pdf)
+ * [pcb artwork](v0.2/telemetrum.pcb.pdf)
+ * [bill of materials](v0.2/partslist.csv)
+* These are as of the working-v0.1 tag:
+ * [schematic](v0.1/telemetrum.pdf)
+ * [pcb artwork](v0.1/telemetrum.pcb.pdf)
+ * [bill of materials](v0.1/telemetrum.bom)
+
+Our [AltOS](../AltOS) firmware works well enough that we now routinely fly
+TeleMetrum with no backup. Rockets with v0.1 boards have exceeded 50g
+acceleration, been above Mach 1, and reached altitudes greater
+than 12k feet AGL with great results. Keith's ground station program
+called ao-view logs telemetry to disk, displays current and max values for
+key parameters during flight, and even includes voice synthesis
+during the flight so that our eyes can stay on the rockets! We have post
+flight analysis software that makes it easy to extract data from the board,
+analyze it, and even generate KML files for viewing flights in GoogleEarth!
+More details on the software, including full source code and pre-built packages
+can be found on the [AltOS](../AltOS) page on this site.
+
+## Future Plans ##
+
+As of early February 2010, three prototypes of v0.2 are done and working on
+the bench. We hope to flight test them shortly, then arrange a production
+run in time to make TeleMetrum available in assembled and tested form to
+others in the rocketry hobby who have expressed interest in time for the
+2010 flying season.
+
+Because we understand that not everyone uses Linux, we've started discussing
+the best way to make a cross-platform ground station program for use with
+[AltOS](../AltOS), perhaps in Java...
projects / web / altusmetrum / blobdiff