This 32 GPIO extension board provides 32 channels designed for use on the Raspberry Pi. The board is based around the MCP23017 16-bit I/O expander from Microchip Technology Inc.

Features:

• A pair of MCP23017 expanders are included on the board allowing you to connect up to 32 digital inputs or outputs to the Raspberry Pi. The 32 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 32 GPIO along with other expansion boards.
• Extra i2c pin for easy connections to other devices
• Each 23017 address can be rearranged to your needs by changing the A0, A1, A2 address selector pins
• 32 LEDs that show the status of the GPIO

Technical specifications:

• 23017 U13, U14 with GPIO Port A and B
• Output of each GPIO to 2x10 pin:
• Bank B (1-10) GPIO (0, 1, 2, 3, 4, 5, 6, 7, GND, INTB)
• Bank A (1-10) GPIO (0, 1, 2, 3, 4, 5, 6, 7, GND, INTA)
• R61, R62, R63  (for U13 Address select A0, A1, A2)

• R64, R65, R66 (for U14 Address select  A0, A1, A2)
• U13 (20)  23017 -1  Port A, B    U14 (21)   23017-2 Port A, B
• 23017 Datasheet

• A0, A1, A2 address select

  • right side: GND low - 0 and left side: VCC High - 1

    000 - 20    001 - 21   010 - 22   011 - 23

    100 - 24    101 - 25   110 - 26   111 - 27