The Fab ISP is an in-system programmer for AVR microcontrollers, designed for production within a Fab Lab. That is, it allows you to program the microcontrollers on other boards you make, using nothing but a USB cable and 6-pin IDC to 6-pin IDC cable. It’s based on the USB tiny and V-USB firm wares, which allow the ATtiny44 to perform USB communication in software.
Programming can be done through avrdude. The schematic (PDF) is super simple: USB connector, ATtiny44, and 6-pin ISP header, with assorted passive components. I started with the Eagle files for the USB tiny ISP, although there’s almost nothing left of it.
Most of the parts for the Fab ISP are in the Fab Lab inventory. Exceptions include the Mini-B USB connector (Spark Fun, Digi-Key), 12 MHz crystal (Digi-Key), and 18 pF capacitors for the crystal (Digi-Key).
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