Rasberry Pi Serial IO Board

This project is a serial IO / breakout daughter-board for the Rasberry Pi that includes a 7-30v wide range power supply, RS-232 compliant interface and 6 GPIO signal pins with 5v level shifter.

Sample Image of Physical Board
(click for larger version)


  • Daughter-board format which sits directly on the Raspberry Pi pin header without requiring a ribbon cable,
  • Includes switch mode power supply with input voltage range of 7v to 30v which provides power to the Pi without requiring the USB power be connected,
  • Choice of barrel connector or terminal block for power connection
  • Provides RS232 serial output using MAX3223 level shifter
  • Provides six GPIO pins, either straight 3.3v pass-through from the Pi, or converted to 5v using MAX13000 level shifter (level must be chosen at build time)


The project was built using the gEDA suite, including gschem and pcb. The files below are for those programs:

Schematic: SCH File / PDF Export

Layout: PCB File / PDF Export


Version 1.0 of the board has been manufactured and is currently being shipped back to us.


The Raspberry Pi Serial IO Board is licenced under the CERN Open Hardware Licence v1.1 (TXT, PDF)