MCP23S17 I/O Expander

16-Bit I/O Expander with Serial Interface (SPI)

Hello World

Import programMCP23S17_Basic_IO_Demo

A simple IO demo using the MCP23S17 library


Import programMCP23S17

v 0.4



This SPI I/O expander chip has an internal power on reset and you can just tie the reset pin high (don't just leave it floating) - per data sheet at it must be "externally biased".
Make sure that you order the chip in a skinny DIP package it you want to plug it directly in the breadboard. It also comes in surface mount.

DigiKey stocks and sells both SPI and I2C versions in a DIP for around $1.50.

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