# TelePyro

This is an 8-channel pyro expansion board for [TeleMetrum](../TeleMetrum/).

## Motivation ##

It would be nice to support more than the 2 channels of igniter control
included in the stock [TeleMetrum](../TeleMetrum/) design, so that we can
fly more complex projects involving staging, air starts, and backup ejection
charges.  We also want to experiment with better circuits for testing igniter
continuity, with the hope of being able to measure actual resistance and not
just continuity.

## Features ##

### User View ###

* Small circuit board mounted near [TeleMetrum](../TeleMetrum/)
* Requires [TeleMetrum](../TeleMetrum/) v0.2 or later, as v0.1 does not 
  have the required companion board interface
* Connections for 8 distinct igniter firing channels provided
* Supports use of separate battery for ejection charges

### Developer View ###

* [Atmel ATtiny48](http://www.atmel.com/dyn/products/product_card_v2.asp?PN=ATtiny48) Microcontroller
	* 4k Flash
	* 256 bytes SRAM
	* 64 bytes EEPROM
	* 8-channel 10-bit ADC
	* SPI target interface
	* In-system programming interface
* Software Features (planned)
	* programmed in C using gcc-avr
	* Runs from on-chip flash, uses on-chip RAM
* Tools Used
	* [gEDA](http://www.gpleda.org/) for schematic capture and PCB layout
* Licenses
	* 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)

## Artifacts ##

A schematic exists on [git.gag.com](http://git.gag.com) in the project 
[hw/telepyro](http://git.gag.com/?p=hw/telepyro;a=summary), 
but no prototypes have been built yet.