M5StickC PLUS2 IR Transmitter with Home Assistant

February 22, 2026

Most example ESPHome configs for the M5StickC (this thread, this one, airy10's repo) use GPIO9 for the IR transmitter. The PLUS2 moved it to GPIO19 (official docs).

I used mine to control this IR candle through Home Assistant.

M5StickC PLUS2 and IR candle

I used a Flipper Zero to sniff the NEC codes off the candle's remote:

ON: address 0xFF00, command 0xFE01
OFF: address 0xFF00, command 0xFF00

Flashing

Generate the .bin from the ESPHome add-on in Home Assistant, then flash it via ESPHome Web over USB. If you try to flash directly from ESPHome Web without the HA-generated binary, the WiFi config won't work.

ESPHome config

The important bit is GPIO19 for the IR pin. Swap out the NEC addresses/commands for your device:

esp32:
  board: m5stick-c
  framework:
    type: esp-idf
 
# M5StickC PLUS2 IR transmitter — GPIO19, not GPIO9!
remote_transmitter:
  pin:
    number: GPIO19
  carrier_duty_percent: 50%
  id: internal_ir
 
# Expose as a light entity in Home Assistant
light:
  - platform: binary
    name: "IR Light"
    id: ir_light
    output: ir_light_output
 
output:
  - platform: template
    id: ir_light_output
    type: binary
    write_action:
      - if:
          condition:
            lambda: 'return state;'
          then:
            - remote_transmitter.transmit_nec:
                transmitter_id: internal_ir
                address: 0xFF00      # your device address
                command: 0xFE01      # your ON command
                command_repeats: 1
          else:
            - remote_transmitter.transmit_nec:
                transmitter_id: internal_ir
                address: 0xFF00      # your device address
                command: 0xFF00      # your OFF command
                command_repeats: 1

I used light + binary instead of a switch so Home Assistant treats it as a light entity with a proper toggle.

PLUS2 pinout reference

Function	Pin
IR Transmitter	GPIO19
SPI CLK	GPIO13
SPI MOSI	GPIO15
I2C Internal SDA/SCL	GPIO21 / GPIO22
I2C External SDA/SCL	GPIO0 / GPIO26
Button A	GPIO37
Button B	GPIO39

See the M5Stack docs for the full pinout.