The 128 GPIO board provide 128 channel digital expansion board designed for use on the Raspberry Pi.

 The board is based around the MCP23017 16-bit I/O expander from Microchip Technology Inc.

A pair of MCP23017 expanders are included on the board allowing you to connect up to 128 digital 

inputs or outputs to the Raspberry Pi. The 128 GPIO board is powered through the host Raspberry Pi 

using the GPIO port and extended pins on the GPIO connector allow you to stack the 128 GPIO along with other expansion boards.

1. JP4    U1 Port A       JP3     U1 Port B

2. JP7    U2 Port A        JP8    U2 Port B

3. JP2    U3 Port A       JP1     U3 Port B

4. JP5    U4 Port A        JP6    U4 Port B

5. JP11  U5 Port A       JP12    U5 Port B

6. JP13   U6 Port A       JP14   U6 Port B

7. JP16   U7 Port A       JP15   U7 Port B

8. JP10   U8 Port A       JP9     U8 Port B

9. U1 (20)  23017 -1  Port A,B    U2 (21)   23017-2 Port A,B

10. U3 (22)  23017 -3  Port A,B    U4 (23)   23017-4 Port A,B

11. U5 (24)  23017 -1  Port A,B    U6 (25)   23017-2 Port A,B

12. U7 (26)  23017 -3  Port A,B    U8 (27)   23017-4 Port A,B

 13. J1 i2c signal input  (PIN 1-4) GND, 5V, SDA, SCL  

Download sample program 

 led-21.py   led-22.py  23017-21.py  23017-22.py

  23017-8port-s-v103.py

Download    User Manual        23017 Datasheet