Microchip MCP23018 GPIO (I2C)
Summary
Provides GPIO expansion via I2C using the Microchip MCP23018 chip with ports A and B.
Description
The **Microchip MCP23018 GPIO (I2C)** component exposes 16 digital GPIO pins organized in two banks:
- Port A: Channel[0] – Channel[7]
- Port B: Channel[0] – Channel[7]
Each channel can be independently configured as input or output, with support for inversion and internal pull-ups.
Diagram:
Properties
- Address (i2c) – I2C address of the MCP23018.
Per-Channel Properties (A[0]–A[7], B[0]–B[7])
| Property | Type | Description |
|---|---|---|
| Auto Config | boolean | Automatically configure channel at startup |
| Initial Value | boolean | Initial digital value if configured as output |
| Is Inverted | boolean | Invert logic for this channel |
| Is Output | boolean | Configure as output (otherwise input) |
| Is Pull Up | boolean | Enable internal pull-up when configured as input |
Pins
Channel Pins
| Channel | In (digital) | Out (digital) |
|---|---|---|
| A0 | ✓ | ✓ |
| A1 | ✓ | ✓ |
| A2 | ✓ | ✓ |
| A3 | ✓ | ✓ |
| A4 | ✓ | ✓ |
| A5 | ✓ | ✓ |
| A6 | ✓ | ✓ |
| A7 | ✓ | ✓ |
| B0 | ✓ | ✓ |
| B1 | ✓ | ✓ |
| B2 | ✓ | ✓ |
| B3 | ✓ | ✓ |
| B4 | ✓ | ✓ |
| B5 | ✓ | ✓ |
| B6 | ✓ | ✓ |
| B7 | ✓ | ✓ |
Control Pin
| Pin | Direction | Type | Description |
|---|---|---|---|
| Control | I/O | i2c | I2C communication pin |
Categories
- File:TArduinoDigitalCategory.png Category Digital – Provides digital I/O expansion.
- File:TArduinoI2CCategory.png Category I2C – Communicates using I2C protocol.
