I2C

Parameters for the operation of the VFAT board are downloaded to the chip using the I2C protocol.
A good overview of I2C is available on wikipedia

Electrical Characteristics

The I2C specification limits the I2C bus capacitance to 400pF. The cat5e wire specification limits wire capacitance to 50pF/m, so we should be able to push I2C at least 8m. Testing is needed, but by lowering the bus clock and the pull-up resistors a much greater length should be possible.

Task List

1. Basic I2C working from Gumstix (completed)
2. VFAT powered on and responding to I2C
3. I2C controlled from a C program on Gumstix
4. I2C transmission line testing
5. Interface Gumstix to controller computer (sockets/web?)

Stuff to buy

• Power Supply
• Gumstix (x2)
  • Motherboard
  • Network card
  • Breakout Board
  • Power Plug
  • CF Card
• I2C expanders
• I2C eproms (for feedback testing)
• header pins
• header pin connectors
• LED's