IO programming using PiRT-Unit

This Book explains how to combine Raspberry Pi and PiRT-Unit from OpenRTM-aist.

(G)Using PiRT-Unit

PiRT-Unit is an IO expansion board for Raspberry Pi developed at AIST. It is on sale from Win electronics industry.

You can use AD (4ch), DA (2ch), PWM (1ch), I2C (1ch), RS232C/XBee (1ch) from PiRT-Unit respectively.

PiRT-Unit I/O connector arrangement diagram


  • Analog input (10bit ADC x 4ch) available
  • Analog output (12bit DAC x 2ch) available
  • PWM x 1 ch: RC servo motor available
  • I2C serial communication available
  • RS232C Dsub connector available
  • Connector for Xbee connection available (Selectable with RS232C above)
  • 5V dc input: can supply power to Raspberry Pi
  • You can use the AC adapter that can be purchased cheaply by Akizuki Electronics etc.


Raspberry Pi extended IO board
AD converter 10bit, 4ch & br; chip: ADC104S021
sampling 200kHz
DA converter 12bit, 2ch & br; chip MCP4822
PWM output 1ch, for RC servomotor drive
photo coupler insulation
RS232C D-SUB 9 pin connector
Switch with XBee and jumper
XBee XBee connection connector
XBee: Digi International made Zigbee module
Switch with XBee and jumper
Power supply input 5V DC input
Supply power to Raspberry Pi
Power supply from Raspberry Pi also works

PiRT-Unit circuit block diagram


latest Releases

For Begginers

Windows msi(installer) package (only trying samples)


Development environment is required for RT-Component development. See download page for details.

Number of Projects


Motion editor/Dynamics simulator


Dynamics simulator


Integrated Development Platform

AIST RTC collection

RT-Components collection by AIST


Tokyo Opensource Robotics Association


Middleware for DAQ (Data Aquisition) by KEK