Introduction

The AD8232 ECG Sensor Module is a compact board that measures electrical activity of the heart. This single-lead ECG front end is designed for portable, low-power applications and works perfectly with Arduino for heart rate monitoring projects.

Key Features

Technical Specifications

Pin Configuration

Electrode Placement

Standard Lead I Configuration:

• RA (Right Arm): Right side of chest
• LA (Left Arm): Left side of chest
• RL (Right Leg): Ground reference

For best results, clean skin and use conductive gel

Basic ECG Monitoring

// AD8232 ECG Basic Monitoring
const int ecgPin = A0;
const int loPlus = 2;
const int loMinus = 3;

void setup() {
  Serial.begin(9600);
  pinMode(loPlus, INPUT);
  pinMode(loMinus, INPUT);
}

void loop() {
  if((digitalRead(loPlus) == 1 || (digitalRead(loMinus) == 1)){
    Serial.println("Electrode disconnected!");
  }
  else {
    int ecgValue = analogRead(ecgPin);
    Serial.println(ecgValue);
  }
  delay(10);
}

Advanced Features

// Detect R-peaks and calculate BPM
unsigned long lastBeat = 0;
float threshold = 520; // Adjust based on signal
float bpm = 0;

if(ecgValue > threshold && millis() > lastBeat + 200){
  bpm = 60000 / (millis() - lastBeat);
  lastBeat = millis();
  Serial.print("BPM: "); Serial.println(bpm);
}

// Simple moving average filter
#define FILTER_SIZE 5
int filterBuffer[FILTER_SIZE];
int filterIndex = 0;
int filteredValue = 0;

filterBuffer[filterIndex] = ecgValue;
filterIndex = (filterIndex + 1) % FILTER_SIZE;
for(int i=0; i<FILTER_SIZE; i++){
  filteredValue += filterBuffer[i];
}
filteredValue /= FILTER_SIZE;

// Log ECG data to SD card
#include 
#include 

File ecgFile;

void setup(){
  SD.begin(4); // CS pin
  ecgFile = SD.open("ecg.csv", FILE_WRITE);
}

void loop(){
  ecgFile.print(millis());
  ecgFile.print(",");
  ecgFile.println(ecgValue);
}

// Stream ECG via Bluetooth
#include 

SoftwareSerial btSerial(10, 11); // RX, TX

void setup(){
  btSerial.begin(9600);
}

void loop(){
  btSerial.println(ecgValue);
  delay(10);
}

Troubleshooting