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. Provide 2x 20x2 40 pin same as Pi, one use 40pin GPIO cable connect to Pi

one 20x2 40pinfor GPIO pin extra access.

2.Provide extra i2c pin and spi pin for easy connect device

3. Provide 128 GPIO status blue LED

4Provide each 23017 Address select A0,A1,A2

can rearrange23017 location by your order

5.U2 ,U3 ,U4, U5 ,U6 ,U7,U8 ,U9 23017 Port A,B

6. Each GPIO pin out 2X10 ,