Unit EXT.IO2 / Stamp IO ESPHome Component

The Unit EXT.IO2 / Stamp IO component expands GPIO, ADC, PWM, and other input/output functions over I2C.

1. Component Overview

2. Component Details

External Component Integration

• M5Stack External Component - extio2

Add the External Components configuration to the YAML file to load the EXT.IO2 / Stamp IO component.

external_components:
  - source: github://m5stack/esphome-yaml/components
    components: [extio2]
    refresh: 0s

Hub Component

Add the Hub component before using any EXT.IO2 functions:

extio2:
  id: extio2_hub

Configurable Options

• id (optional, ID): specifies an ID for the Hub component.
• address (optional, int): I2C address; default 0x45.
• reset (optional, boolean): performs a software reset, sets all pins to output mode and low level; default true.
• pwm_freq (optional, enum): global PWM frequency for all channels; default 1kHz.
  • 2kHz
  • 1kHz
  • 500Hz
  • 250Hz
  • 125Hz
• Other options supported by I2C devices.

GPIO Pins

EXT.IO2 pins can be used wherever ESPHome accepts a standard GPIO pin reference, for example in switch and binary_sensor components.

# Digital output - switch
switch:
  - platform: gpio
    name: "EXT.IO2 GPIO 0"
    pin:
      extio2_id: extio2_hub
      number: 0
      mode:
        output: true

# Digital input - binary sensor
binary_sensor:
  - platform: gpio
    name: "EXT.IO2 GPIO 1"
    pin:
      extio2_id: extio2_hub
      number: 1

Pin Configuration

• extio2_id (required, ID): the ID of the EXT.IO2 bus controller.
• number (required, int): pin number, range 0-7.
• inverted (optional, boolean): inverts the pin logic; default false.
• mode (required): selects input or output, with optional pullup, pulldown, or open_drain flags.

Sensors (ADC)

The sensor platform reads analog values from eight ADC-capable pins.

sensor:
  - platform: extio2
    extio2_id: extio2_hub
    name: "ADC Sensors 0"
    channel: ADC_0
    resolution: 12BIT
    update_interval: 5s

Configuration

• extio2_id (optional, ID): the ID of the EXT.IO2 bus controller.
• channel (required, enum): ADC channel to read, from ADC_0 to ADC_7.
• resolution (optional, enum): ADC resolution; default 8BIT.
  • 8BIT: 8-bit resolution, range 0-255.
  • 12BIT: 12-bit resolution, range 0-4095.
• update_interval (optional, time): polling interval; default 60s.
• For other options, see Sensors.

Output (PWM)

The output platform drives any pin as a PWM output. The duty cycle is represented as a floating-point value from 0.0 to 1.0, internally mapped to 0-100%.

output:
  - platform: extio2
    extio2_id: extio2_hub
    id: pwm_ch0
    channel: PWM_0

light:
  - platform: monochromatic
    name: "PWM Light 0"
    output: pwm_ch0
    effects:
      - pulse:

Configuration

• extio2_id (optional, ID): the ID of the EXT.IO2 bus controller.
• id (required, ID): the ID of this output.
• channel (required, enum): PWM channel to use, from PWM_0 to PWM_7.
• For other options, see Float Output.

Number (Servo)

The number platform controls servos in two modes: angle (degrees) and pulse width (microseconds).

Angle Mode

Controls the servo position by angle (0-180 degrees).

number:
  - platform: extio2
    extio2_id: extio2_hub
    name: "Servo 0"
    type: angle
    channel: SERVO_0
    min_value: 0
    max_value: 180
    step: 3

Pulse-Width Mode

Controls the servo using the raw pulse width (microseconds).

number:
  - platform: extio2
    extio2_id: extio2_hub
    name: "Servo 1"
    type: pulse
    channel: SERVO_1
    min_value: 500
    max_value: 2500
    step: 100

Configuration

• extio2_id (optional, ID): the ID of the EXT.IO2 bus controller.
• type (required, enum): servo control mode.
  • angle: angle control.
  • pulse: pulse-width control.
• channel (required, enum): servo channel to use, from SERVO_0 to SERVO_7.
• min_value (optional, float): minimum value; default 0.0 in angle mode and 500.0 in pulse mode.
• max_value (optional, float): maximum value; default 180.0 in angle mode and 2500.0 in pulse mode.
• step (optional, float): step value; default 3.0 in angle mode and 100.0 in pulse mode.
• For other options, see Number.

Lights

The light platform supports two modes: a single RGB LED on a specified pin, or an addressable LED strip using consecutive pins starting at pin 0.

Single RGB LED

Controls a single RGB LED on the specified pin.

light:
  - platform: extio2
    extio2_id: extio2_hub
    name: "EXT.IO2 Light 2"
    type: light
    channel: LIGHT_2

Addressable LED Strip

Controls consecutive RGB LEDs starting at pin 0 and supports all ESPHome addressable-light effects.

light:
  - platform: extio2
    extio2_id: extio2_hub
    name: "LED Strip"
    type: addressable_light
    num_leds: 8

Configuration

• extio2_id (optional, ID): the ID of the EXT.IO2 bus controller.
• type (required, enum): light mode.
  • light: single RGB LED.
  • addressable_light: addressable LED strip.
• channel (required for light, enum): pin to use, from LIGHT_0 to LIGHT_7.
• num_leds (required for addressable_light, int): number of LEDs, range 1-8, assigned consecutively starting at pin 0.
• For other options, see Light.

3. Example

This example demonstrates the GPIO input/output, ADC, PWM, servo, and RGB light platforms. Adjust the controller I2C pins to match the actual wiring.

i2c:
  sda: GPIO2
  scl: GPIO1

extio2:
  id: extio2_hub
  address: 0x45
  reset: true
  pwm_freq: 1kHz

# GPIO - digital output
switch:
  - platform: gpio
    name: "EXT.IO2 GPIO 0"
    pin:
      extio2_id: extio2_hub
      number: 0
      mode:
        output: true

# GPIO - digital input
binary_sensor:
  - platform: gpio
    name: "EXT.IO2 GPIO 1"
    pin:
      extio2_id: extio2_hub
      number: 1
      mode:
        input: true
        pullup: true

# ADC sensor
sensor:
  - platform: extio2
    extio2_id: extio2_hub
    name: "ADC Sensors 2"
    channel: ADC_2
    resolution: 12BIT
    update_interval: 5s

# PWM output used as a monochromatic light
output:
  - platform: extio2
    extio2_id: extio2_hub
    id: pwm_ch3
    channel: PWM_3

light:
  - platform: monochromatic
    name: "PWM Light 3"
    output: pwm_ch3
    effects:
      - pulse:

  # Single RGB LED
  - platform: extio2
    extio2_id: extio2_hub
    name: "RGB Light 6"
    type: light
    channel: LIGHT_6

  # Addressable LED strip (all 8 pins)
  - platform: extio2
    extio2_id: extio2_hub
    name: "LED Strip"
    type: addressable_light
    num_leds: 8

number:
  # Servo - angle control
  - platform: extio2
    extio2_id: extio2_hub
    name: "Servo 4"
    type: angle
    channel: SERVO_4

  # Servo - pulse-width control
  - platform: extio2
    extio2_id: extio2_hub
    name: "Servo 5"
    type: pulse
    channel: SERVO_5

4. Related Links

• Unit EXT.IO2 Product Page
• Stamp IO Product Page
• EXT.IO2 Complete External Component Example