💖 ESP32 Heart Rate LED Pulse This repository contains the Arduino sketch for an ESP32 project that reads heart rate data from the MAX30105 Pulse Oximeter Sensor and translates the live beats per minute (BPM) into a smooth, rhythmic pulse on an LED.
✨ Features Heart Rate Sensing: Uses the MAX30105 sensor to detect blood flow and calculate BPM.
I2C Communication: Configured for the default ESP32 I2C pins (SDA 21, SCL 22).
Smooth Visual Pulse: The LED fades up and down over a 300ms duration on every detected heartbeat.
BPM Synchronization: The blinking interval is dynamically adjusted to synchronize with the calculated average heart rate.
No Finger Detection: Logs "No finger?" to the Serial Monitor and turns off the LED if the IR reading is too low.
🛠️ Hardware Requirements Component Description Microcontroller ESP32 Development Board (e.g., ESP32-DevKitC) Sensor MAX30105 Pulse Oximeter and Heart Rate Sensor LED 5mm LED (any color) Resistor Current-limiting Resistor (e.g., 220 Ohm) Cables Jumper Wires
🔌 Wiring Guide The sketch uses the specified I2C pins for the MAX30105 and GPIO 4 for the LED. MAX30105 VCC 3.3V Power supply MAX30105 GND GND Ground MAX30105 SDA GPIO 21 I2C Data Pin MAX30105 SCL GPIO 22 I2C Clock Pin LED Anode (+) GPIO 4 (via Resistor) PWM Output LED Cathode (-) GND Ground
⚙️ Software Setup Arduino IDE & Libraries Install the ESP32 Board Manager: Ensure you have the ESP32 core installed in the Arduino IDE.
Install Libraries: Open the Arduino Library Manager and install the following dependencies:
SparkFun MAX30105 (by SparkFun Electronics)
SparkFun Heart Rate Algorithm (or similar accompanying library used for heartRate.h)
Select your ESP32 board and the correct COM port.
Upload the code.
Open the Serial Monitor at 115200 baud to view real-time BPM and sensor data.
Place your finger gently but firmly over the sensor. After a few seconds, the LED will begin to pulse at your current heart rate.