M5Stack Stamp C3

Verified

Checked on hardware (2026-10-10): this template on a Stamp C3 (ESP32-C3 rev 0.3). The status LED lights and blinks, and the button reads correctly.

RecommendedCost-conscious pick.

Chip	ESP32-C3
Form factor	Stamp module, 24 × 24 mm (Mate version has pin headers)
Flash	4 MB
Antenna	3D antenna
USB	USB-C (USB-to-serial chip)
Install	Browser installer, esp32c3 flavor
Stores	m5stackaliamz/us

GPIO

GPIO	Function	ESPresense setting
2	SK6812 RGB LED	LEDs
3	Button (active low)	Inputs

Template

Paste this into the Board Template box on the node's Templates page, then Preview and Apply (firmware v5.0.0b1 or later). It sets the board's pins (and Ethernet type, if it has one) in one go. The LED, input and output lists replace what was configured before, so the result doesn't depend on the node's old setup. See Templates.

{"name":"M5 Stamp C3","chip":"esp32c3","settings":{"leds":[{"type":"grb","pin":2,"count":1,"control":"status"}],"inputs":[{"name":"Button","role":"button","pin":3,"type":"pullup_inverted"}],"outputs":[]}}

Copy

Formatted, with what each value means

{
  "name": "M5 Stamp C3",
  "chip": "esp32c3",
  "settings": {
    "leds": [
      {
        "type": "grb",
        "pin": 2,
        "count": 1,
        "control": "status"
      }
    ],
    "inputs": [
      {
        "name": "Button",
        "role": "button",
        "pin": 3,
        "type": "pullup_inverted"
      }
    ],
    "outputs": []
  }
}

LED type: pwm, pwm_inverted, grb, grbw, rgb or rgbw (the last four are addressable). LED control: mqtt, status, motion, count, or output (follows the output numbered byoutput). Input type: pullup, pulldown or floating, with_inverted for active-low. Output type: output, output_inverted, or high/low for a pin that's just held at that level. An output's input is the 1-based input that controls it. power takes ESPHome's hlw8012 values (a cse7766 needs only rx); sel_inverted matches ESPHome's inverted on sel_pin. eth is the Ethernet Type's option number.

Notes

• The generic esp32c3 build defaults to a PWM LED on GPIO 2, but this board’s LED is addressable. Without the template the status LED never lights.
• Install the plain esp32c3 flavor. The board has a USB-to-serial chip, so it doesn’t need esp32c3-cdc. (The Stamp C3U has native USB and does.)
• No I2C is wired on the board, and I2C is off by default.