uDMX is built around a ATMEL ATMega8 microcontroller, very few external parts are used, thanks to Objective Developments firmware only usb driver. There's an external object for Max/MSP and puredata that interfaces directly to the uDMX.

Features

• fits in your pocket
• bus powered - no need for a wall-wart
• can send DMX packets of arbitrary size from 1 to 512 channels. Only got 12 dimmers ? Don’t waste time sending 500 additional zeros 200 times a second…
• command line tool
• external for Max/MSP and PureData
• open source