Circuit Documentation

Summary

This circuit is designed to monitor heart rate using an AD8232 Heart Rate Monitor sensor and an ESP32-S3 microcontroller. The AD8232 sensor captures the heart rate signal and sends it to the ESP32-S3, which processes the signal and outputs the data to a serial monitor. The circuit also monitors the electrode status to ensure proper attachment.

Component List

1. AD8232 Heart Rate Monitor

   • Description: A sensor module used to measure the electrical activity of the heart.
   • Pins: GND, 3.3v, OUTPUT, LO-, LO+, SDN, RA, LA, RL

2. ESP32-S3

   • Description: A powerful microcontroller with built-in Wi-Fi and Bluetooth capabilities.
   • Pins: 3v3, EN, GPIO4, GPIO5, GPIO6, GPIO7, GPIO15, GPIO16, GPIO17, GPIO18, GPIO8, GPIO46, GPIO9, GPIO10, GPIO11, GPIO12, GPIO13, GPIO14, 5V, GND, GPIO43, GPIO44, GPIO1, GPIO2, GPIO42, GPIO41, GPIO40, GPIO39, GPIO38, GPIO37, GPIO36, GPIO35, GPIO0, GPIO45, GPIO48, GPIO47, GPIO21, GPIO20, GPIO19

Wiring Details

AD8232 Heart Rate Monitor

• GND connected to ESP32-S3 GND
• 3.3v connected to ESP32-S3 3v3
• OUTPUT connected to ESP32-S3 GPIO4
• LO- connected to ESP32-S3 GPIO20
• LO+ connected to ESP32-S3 GPIO19

ESP32-S3

• GND connected to AD8232 Heart Rate Monitor GND
• 3v3 connected to AD8232 Heart Rate Monitor 3.3v
• GPIO4 connected to AD8232 Heart Rate Monitor OUTPUT
• GPIO20 connected to AD8232 Heart Rate Monitor LO-
• GPIO19 connected to AD8232 Heart Rate Monitor LO+

Code Documentation

/*
 * Electrocardiograph (ECG) using ESP32-S3 and AD8232 sensor
 * This code reads the heart rate signal from the AD8232 sensor and prints
 * the values to the Serial Monitor. It also monitors the LO+ and LO- pins
 * to detect if the electrodes are properly attached.
 */

// Pin definitions
const int ecgPin = 4; // ECG signal from AD8232 OUTPUT pin
const int loPlusPin = 19; // LO+ pin from AD8232
const int loMinusPin = 20; // LO- pin from AD8232

void setup() {
  // Initialize serial communication
  Serial.begin(115200);

  // Configure pin modes
  pinMode(ecgPin, INPUT);
  pinMode(loPlusPin, INPUT);
  pinMode(loMinusPin, INPUT);
}

void loop() {
  // Read ECG signal
  int ecgValue = analogRead(ecgPin);

  // Read electrode status
  int loPlusStatus = digitalRead(loPlusPin);
  int loMinusStatus = digitalRead(loMinusPin);

  // Print ECG value
  Serial.print("ECG Value: ");
  Serial.println(ecgValue);

  // Check electrode status
  if (loPlusStatus == HIGH || loMinusStatus == HIGH) {
    Serial.println("Electrodes not properly attached!");
  }

  // Delay for stability
  delay(10);
}

This code initializes the necessary pins on the ESP32-S3, reads the ECG signal from the AD8232 sensor, and prints the values to the Serial Monitor. It also checks the status of the LO+ and LO- pins to ensure the electrodes are properly attached.