MAX30102 with ESP32-C3-DevKitM-1

Wiring for the MAX30102 heart rate + SpO2 on the ESP32-C3-DevKitM-1 (ESP32-C3, 3.3 V logic), chosen with the same pin rules BoardPilot uses: default buses first, and no pins that are used for flash, USB, the debugger or booting.

Wiring

MAX30102 pin	Role	ESP32-C3-DevKitM-1 pin	Notes
VIN	Power	3V3
SDA	I2C data (SDA)	8
SCL	I2C clock (SCL)	9
INT	Interrupt	10
IRD	Not wired to the board	not connected	IR LED output. Leave unconnected
RD	Not wired to the board	not connected	Red LED output. Leave unconnected
GND	Ground	GND

Check before you power it on

Supply: 3.3 V from the 3V3 pin.
I2C can use almost any pins on the ESP32-C3-DevKitM-1; 8 (SDA) and 9 (SCL) are the defaults. If the part is not found, the wires may be crossed: try Wire.begin with the two exchanged.
To make sure it is the real chip, read register 0xFF: a genuine part answers 0x15.

Test code (Arduino)

#include <Wire.h>

void setup() {
  Serial.begin(115200);
  Wire.begin(8, 9);  // SDA = 8, SCL = 9
  Wire.beginTransmission(0x57);
  bool found = Wire.endTransmission() == 0;
  Serial.println(found ? "MAX30102 heart rate + SpO2 found at 0x57" : "Not found: check power, GND and SDA/SCL");
}

void loop() {}

Arduino board: esp32:esp32:esp32c3. If uploading does not start, hold BOOT, press and release RST, then release BOOT.

Questions

Which ESP32-C3-DevKitM-1 pins do I use for the MAX30102?

VIN → 3V3, SDA → 8, SCL → 9, INT → 10, GND → GND.

Does the MAX30102 work with the ESP32-C3-DevKitM-1 at 3.3 V?

Yes: the MAX30102 runs at 3.3-5 V and the ESP32-C3-DevKitM-1 uses 3.3 V signals, so no level shifting is needed.

What is the I2C address of the MAX30102?

0x57. An I2C scan (BoardPilot does it for you) shows which one your module uses.

BoardPilot checks this wiring in 3D as you build it, and finds crossed or missing wires on the real board.

Download BoardPilot

Full ESP32-C3-DevKitM-1 pinout · MAX30102 heart rate + SpO2: all pins and data

The MAX30102 on other boards

ESP32 DevKit Arduino Mega 2560 R3 Arduino Nano Arduino Uno R3 WeAct Black Pill STM32F411CE ESP32-S3-DevKitC-1 Nordic nRF52840 DK NUCLEO-F401RE Raspberry Pi Pico 2 Raspberry Pi Pico W Raspberry Pi Pico Teensy 4.1

Other parts on the ESP32-C3-DevKitM-1

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