[DJBecker]

Logic board

The easiest and least expensive approach is to start with a commercial microcontroller for the logic board. We chose
the Arduino hardware platform (AVR ATMega chips) for its easy to use tools and low total
cost.

The software development environment is Open Source, already packaged
for Linux (Ubuntu is especially easy) and quite flexible. While we
don't use the Arduino software environment, loading that package pulls
in the compiler, libraries and downloading tools that are preconfigured
to work.

The platform cost isn't just the development board price, it is also the
add-on pieces. Most boards have built-in USB interfaces, which
elminates the need for a $10-$150 JTAG/ISP programmer. Arduino has a
thriving ecosystem of plug in accessories, especially "shields", circuit
boards that stack on top of the processor board. While proto-shields
cost more ($6-$12) than the least expensive generic protoboards ($2+),
they eliminate wiring to the processor board and mounting hardware. A sensor shield ($8-$14) is a passive board full of connectors that makes it easier to plug in sensor and output modules. You can handle almost everything for a motor controller (temperature, tachometer photosensor, throttle input, contactor relay) with existing modules. Only the isolated gate driver board needs to be custom made.