Library for the MCP23017 I/O Expander
This is a library for the MCP23017, MCP23S17, MCP23018 and MCP23S18 I/O Port Expander.
You’ll find some examples including the wiring (examples folder) which
should enable you to use the library. Furthermore I have added a list of commands.
I have implemented an option to use it with an ATtiny and the TineWireM library.
In case you like this library it would be cool if you give it a star.
If you find bugs, please inform me!
Important notice:
In 2022 Microchip has unfortunately updated the design of the MCP23017. GPA7 and GPB7 have lost their input function:
You can only use these pins as output. There is no change to the MCP23S17, MCP23018 and MCP23S18.
You find this information in latest datasheet:
https://www.microchip.com/en-us/product/mcp23017
Written by Wolfgang (Wolle) Ewald
http://wolles-elektronikkiste.de/portexpander-mcp23017 (German)
https://wolles-elektronikkiste.de/en/port-expander-mcp23017-2 (English)