This is the design that started it all! Bdale got frustrated with existing commercial altimeters and decided to build his own. This project was presented in talks at LCA, SCALE, OLS, and Debconf in 2008.
Here are photos of the front and back sides of the version 0.1 prototype PCB.
## Features ##
### User View ###
* Recording altimeter for model rocketry
* Supports dual deployment (can fire 2 ejection charges)
* Primary operations based on pressure sensor
* 3-axis accelerometer
* Temperature sensor
* 2 serial ports for attachment of GPS and RF link modules
* USB for data recovery and post-flight power source
* Flexible battery choices
* Designed to fit 24mm airframe tube
## Problems ##
In addition to the various "oopses" that were found and fixed during initial
turn-on of this board, several issues contributed to the decision to shelve
the design for now:
* lots of work went in to trying to make the board fit in a 24mm airframe,
but the resulting design with battery is really too heavy for such a small
rocket.
* the 3-axis accelerometer has a max scale of +/- 6g. This is insufficient
for characterizing the kinds of motors that we're playing with now.
* while using a gcc-based toolchain to cross-develop for the ARM7 core works
reasonably well, it's a heavy toolchain to build and maintain, and the
processor really is serious overkill for the task at hand.
## Artifacts ##
The version 0.1 design had enough issues that Bdale decided not to publish
it. Work on an 0.2 revision is mostly complete at the schematic level, and
some printed circuit board artwork updates were made, but a second run of
boards was never attempted. This design is now mostly of historical interest.