ESP32 KY-039 Heartbeat Sensor Module

🛠️ KY-039 Heartbeat Sensor Module Troubleshooting

This guide outlines a systematic approach to troubleshoot and resolve common problems with the . Start by confirming that the hardware connections are correct, as wiring mistakes are the most frequent cause of issues. If you are sure the connections are correct, follow the below steps to debug common issues.

❌ No Signal Detected

⚠️ Unstable or Noisy Readings

💻 Code Examples

Below you can find code examples of KY-039 Heartbeat Sensor Module with ESP32 in several frameworks:

• Arduino IDE
• ESP-IDF
• ESPHome
• PlatformIO
• MicroPython

If you encounter issues while using the KY-039 Heartbeat Sensor Module, check the Common Issues Troubleshooting Guide.

ESP32 KY-039 Arduino IDE Code Example

Example in Arduino IDE

Fill in your main Arduino IDE sketch file with the following code to use the KY-039 Heartbeat Sensor Module:

#define SENSOR_PIN A0

void setup() {
    Serial.begin(9600);
    pinMode(SENSOR_PIN, INPUT);
    Serial.println("KY-039 Heartbeat Sensor Test");
}

void loop() {
    int sensorValue = analogRead(SENSOR_PIN);
    Serial.println(sensorValue);
    delay(10);
}

This Arduino code initializes the analog pin connected to the KY-039 sensor. It reads the analog value corresponding to the heartbeat signal and prints it to the serial monitor every 10 milliseconds. Users can observe the serial plotter to visualize the heartbeat waveform.

Connect your ESP32 to your computer via a USB cable, Ensure the correct Board and Port are selected under Tools, Click the "Upload" button in the Arduino IDE to compile and upload the code to your ESP32.

ESP32 KY-039 ESP-IDF Code Example

Example in Espressif IoT Framework (ESP-IDF)

If you're using ESP-IDF to work with the KY-039 Heartbeat Sensor Module, here's how you can set it up and read data from the sensor. Fill in this code in the main ESP-IDF file:

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/adc.h"

#define SENSOR_CHANNEL ADC1_CHANNEL_6 // GPIO34

void app_main(void) {
    adc1_config_width(ADC_WIDTH_BIT_12);
    adc1_config_channel_atten(SENSOR_CHANNEL, ADC_ATTEN_DB_11);

    printf("KY-039 Heartbeat Sensor Test\n");
    while (1) {
        int raw = adc1_get_raw(SENSOR_CHANNEL);
        float voltage = raw * (3.3 / 4095.0);
        printf("Analog Voltage: %.2f V\n", voltage);
        vTaskDelay(pdMS_TO_TICKS(10));
    }
}

This ESP-IDF code configures GPIO34 as an analog input for the KY-039 heartbeat sensor. It reads the analog voltage corresponding to the heartbeat signal and prints it to the console every 10 milliseconds, allowing for real-time monitoring of the pulse waveform.

Update the I2C pins (I2C_MASTER_SDA_IO and I2C_MASTER_SCL_IO) to match your ESP32 hardware setup, Use idf.py build to compile the project, Use idf.py flash to upload the code to your ESP32.

ESP32 KY-039 ESPHome Code Example

Example in ESPHome (Home Assistant)

Fill in this configuration in your ESPHome YAML configuration file (example.yml) to integrate the KY-039 Heartbeat Sensor Module

sensor:
  - platform: adc
    pin: GPIO34
    name: "KY-039 Heartbeat Sensor"
    update_interval: 10ms
    filters:
      - multiply: 3.3
      - lambda: |-
          return x * 1000;  // Convert to millivolts

This ESPHome configuration sets up the KY-039 sensor connected to GPIO34. It reads the analog value every 10 milliseconds, converts it to millivolts, and makes it available as a sensor named "KY-039 Heartbeat Sensor" for further processing or visualization.

Upload this code to your ESP32 using the ESPHome dashboard or the esphome run command.

ESP32 KY-039 PlatformIO Code Example

Example in PlatformIO Framework

For PlatformIO, make sure to configure the platformio.ini file with the appropriate environment and libraries, and then proceed with the code.

Configure platformio.ini

First, your platformio.ini should look like below. You might need to include some libraries as shown. Make sure to change the board to your ESP32:

[env:esp32]
platform = espressif32
board = esp32dev
framework = arduino

ESP32 KY-039 PlatformIO Example Code

Write this code in your PlatformIO project under the src/main.cpp file to use the KY-039 Heartbeat Sensor Module:

#include <Arduino.h>

#define SENSOR_PIN 34

void setup() {
    Serial.begin(115200);
    Serial.println("KY-039 Heartbeat Sensor Test");
}

void loop() {
    int sensorValue = analogRead(SENSOR_PIN);
    float voltage = sensorValue * (3.3 / 4095.0) * 1000; // Convert to millivolts
    Serial.printf("Analog Voltage: %.2f mV\n", voltage);
    delay(10);
}

This PlatformIO code sets up GPIO34 as an analog input for the KY-039 heartbeat sensor. It continuously reads the sensor value, converts it to millivolts, and prints it to the serial monitor every 10 milliseconds to capture the heartbeat waveform.

Upload the code to your ESP32 using the PlatformIO "Upload" button in your IDE or the pio run --target upload command.

ESP32 KY-039 MicroPython Code Example

Example in Micro Python Framework

Fill in this script in your MicroPython main.py file (main.py) to integrate the KY-039 Heartbeat Sensor Module with your ESP32.

import machine
import time

SENSOR_PIN = machine.ADC(machine.Pin(34))
SENSOR_PIN.atten(machine.ADC.ATTN_11DB)

while True:
    sensor_value = SENSOR_PIN.read()
    voltage = (sensor_value / 4095) * 3300  # Convert to millivolts
    print("Analog Voltage:", voltage, "mV")
    time.sleep(0.01)

This MicroPython script configures GPIO34 as an ADC input for the KY-039 heartbeat sensor. It continuously reads the sensor value, converts it to millivolts, and prints the voltage every 10 milliseconds for real-time heartbeat monitoring.

Upload this code to your ESP32 using a MicroPython-compatible IDE, such as Thonny, uPyCraft, or tools like ampy.