Daniel Amesberger has designed a tiny expansion board called the RasPiComm to make use of the extension header of the Raspberry Pi board. It connects to the RPi in a similar way to the shields for the Arduino board.
The board comes with the following extensions:
- RS-485 port – Mainly used to control stepper motors.
- RS-232 (‘serial’) port – It can be used to access the serial console over “/dev/ttyAMA0″ serial device, which can be very useful for headless systems.
- 5 inputs connected to an onboard joystick and screw terminals
- 2 outputs (5V) with LEDs (green and red) also connected to screw terminals
- I2C connection – There are plenty of things you can do with I2C connections (Sensors, RTC, …), and Daniel successfully connected a tiny 128×64 I2C OLED display.
- Real time clock (RTC) with backup battery – Very useful for offline use if you need to keep track of the time.
There is currently only one prototype, but Daniel expects to manufacture more pieces soon, and the price might fall to $25 to $30 per pieces, if he can order 1k or more. A large version “B” expansion board might also be developed in the future with onboard power supply, CAN support and more, depending on users’ feedback.
More information is available on Daniel’s blog, and a post about hardware and software details should follow soon.