Home-Assistant-Dev/components/tca6408

TCA6408 ESPHome Component

Full-featured custom component for the TCA6408 8-bit I²C I/O Expander.

This is work in progress and under test

Features

• 8 bidirectional GPIO pins
• Hardware polarity inversion support (inputs)
• Interrupt-driven inputs (active-low INT pin)
• Efficient cached GPIO expander
• Polling fallback mode
• Compatible with ESP32 (including C3/C5/C6), ESP8266, etc.

The INT pin on TCA6408 is open-drain active-low — connect a pull-up resistor (or use internal pull-up on ESP).

Installation

1. Download or clone this component into your ESPHome project:

   mkdir -p custom_components
   cp -r TCA6408/custom_components/tca6408 custom_components/
   

Basic Configuration

i2c:
  sda: GPIO4
  scl: GPIO5
  scan: true
  frequency: 400kHz

custom_components:
  - source:
      type: local
      path: custom_components/tca6408

tca6408:
  - id: tca6408_hub
    address: 0x20                    # Default: 0x20 (0x20–0x27 depending on ADDR pins)
    interrupt_pin: GPIO6             # Recommended for fast input response

Example: Outputs (Switches)

switch:
  - platform: gpio
    name: "TCA6408 Output 0"
    pin:
      tca6408: tca6408_hub
      number: 0
      mode: OUTPUT

  - platform: gpio
    name: "TCA6408 Relay (Active Low)"
    pin:
      tca6408: tca6408_hub
      number: 1
      mode: OUTPUT
      inverted: true

Example: Inputs (Binary Sensors) with Interrupt

binary_sensor:
  - platform: gpio
    name: "Door Sensor"
    pin:
      tca6408: tca6408_hub
      number: 3
      mode: INPUT
      inverted: true           # Uses hardware polarity inversion

  - platform: gpio
    name: "Push Button"
    pin:
      tca6408: tca6408_hub
      number: 4
      mode: INPUT