Knowledge Base

The AB Electronics UK Knowledge Base provides support solutions, tutorials and troubleshooting guides.

Knowledge Base

IO Zero 32

The IO Zero 32 is a 32-channel digital GPIO expansion board designed for the Raspberry Pi and other compatible single-board computers. The board is based around the PCA9535 16-bit I/O expander from NXP. A pair of PCA9535 expanders are included on the board, allowing you to connect up to 32 digital inputs or outputs to the Raspberry Pi. The IO Zero 32 is powered through the host Raspberry Pi using the GPIO port, and extended pins on the GPIO connector allow you to stack the IO Zero 32 along with other expansion boards.

This knowledge base section contains articles and tutorials on the IO Zero 32, showing how to use the expansion board with various devices.

Find out more about the IO Zero 32.

Photo of IO Zero 32

IO Zero 32 with Raspberry Pi Pico

You can use the IO Zero 32 expansion board with the Raspberry Pi Pico development boards. We have a MicroPython library to use with the Raspberry Pi Pico at GitHub at

IO Zero 32 Tutorial 1 - The Blinking LED

This tutorial will start with a blinking LED and build a binary counter using 8 LEDs. You will need your Raspberry Pi, an IO Zero 32, 8 red LEDs, and 8 500R resistors....

IO Zero 32 Tutorial 2 - Push the Button

In this tutorial, we will add a button and an LED to the IO Zero 32 and detect when the button has been pressed. You will need your Raspberry Pi, an IO Zero 32, one red LED, one 500R resistor, one 100K resistor and a push button....