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MCP23017

Build Status License

This library provides full control over the Microchip's MCP23017, including interrupt support.

Features

  • Individual pins read & write
  • Ports read & write
  • Registers read & write
  • Full interrupt support

Usage

Unlike most Arduino library, no default instance is created when the library is included. It's up to you to create one using the appropriate I2C address based on MCP23017 A0, A1 and A2 pins wirings. Available addresses go from 0x20 to 0x27, allowing up to 8 MCP23017 on the same I2C bus.

#include <Arduino.h>
#include <MCP23017.h>

MCP23017 mcp = MCP23017(0x24);

Additionaly, you can specify the Wire instance to use as a second argument. For instance MCP23017(0x24, Wire1).
See included examples for further usage.

Warning about GPA7 & GPB7

GPA7 or GPB7 should not be used as inputs despite what the configuration registers allow. As stated by Microchip, it can lead to SDA signal corruption or even malfunction in the host bus under some conditions.

Breaking changes in v2.0.0

Major renames have been performed in v2.0.0 to improve compatibility with a variety of platforms. Existing code will break when you update from version v1.x.

Name in v1.x Name in v2.x
MCP23017_PORT MCP23017Port
MCP23017_REGISTER MCP23017Register
MCP23017_INTMODE MCP23017InterruptMode

In addition to this, every member of the MCP23017Register enum were renamed to avoid possible conflicts with macro definitions. GPIOA was renamed to GPIO_A, INTCAPA to INTCAP_A and so on...