ESP32 KY-035 Analog Hall Magnetic Sensor Module

🛠️ KY-035 Analog Hall Magnetic 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 Output Signal

⚠️ Incorrect or Fluctuating Readings

💻 Code Examples

Below you can find code examples of KY-035 Analog Hall Magnetic Sensor Module with ESP32 in several frameworks:

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

If you encounter issues while using the KY-035 Analog Hall Magnetic Sensor Module, check the Common Issues Troubleshooting Guide.

ESP32 KY-035 Arduino IDE Code Example

Example in Arduino IDE

Fill in your main Arduino IDE sketch file with the following code to use the KY-035 Analog Hall Magnetic Sensor Module:

int sensorPin = A0; // The input pin for the sensor

void setup() {
    Serial.begin(9600);
    Serial.println("KY-035 Magnetic Field Detection");
}

void loop() {
    int rawValue = analogRead(sensorPin);
    float voltage = rawValue * (5.0 / 1023.0) * 1000;  // Convert to millivolts
    Serial.print("Voltage: ");
    Serial.print(voltage);
    Serial.println(" mV");
    delay(1000);
}

This Arduino code initializes the serial communication and reads the analog value from the KY-035 sensor connected to pin A0. It converts the raw analog value to voltage in millivolts and prints it to the serial monitor every second.

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-035 ESP-IDF Code Example

Example in Espressif IoT Framework (ESP-IDF)

If you're using ESP-IDF to work with the KY-035 Analog Hall Magnetic 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-035 Magnetic Field Detection\n");
    while (1) {
        int raw = adc1_get_raw(SENSOR_CHANNEL);
        float voltage = raw * (3.3 / 4095.0) * 1000; // Convert to millivolts
        printf("Voltage: %.2f mV\n", voltage);
        vTaskDelay(pdMS_TO_TICKS(1000));
    }
}

This ESP-IDF code configures ADC1 channel 6 (GPIO34) to read analog values from the KY-035 sensor. It converts the raw ADC value to voltage in millivolts and prints it to the console every second.

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-035 ESPHome Code Example

Example in ESPHome (Home Assistant)

Fill in this configuration in your ESPHome YAML configuration file (example.yml) to integrate the KY-035 Analog Hall Magnetic Sensor Module

sensor:
  - platform: adc
    pin: GPIO34
    name: "KY-035 Magnetic Field Sensor"
    update_interval: 1s
    filters:
      - multiply: 3.3
      - lambda: |-
          return x * 1000;  // Convert to millivolts

This ESPHome configuration sets up the KY-035 sensor connected to GPIO34 as an ADC sensor. It reads the analog voltage every second, converts it to millivolts, and logs the value. The lambda function ensures the output is in millivolts for easier interpretation.

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

ESP32 KY-035 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-035 PlatformIO Example Code

Write this code in your PlatformIO project under the src/main.cpp file to use the KY-035 Analog Hall Magnetic Sensor Module:

#include <Arduino.h>

#define SENSOR_PIN 34

void setup() {
    Serial.begin(115200);
    Serial.println("KY-035 Magnetic Field Sensor Test");
}

void loop() {
    int raw_value = analogRead(SENSOR_PIN);
    float voltage = raw_value * (3.3 / 4095.0) * 1000; // Convert to millivolts
    Serial.print("Magnetic Field Voltage: ");
    Serial.print(voltage);
    Serial.println(" mV");
    delay(1000);
}

This PlatformIO code sets up GPIO34 as an analog input for the KY-035 sensor. It reads the raw ADC value, converts it to millivolts, and logs it to the serial monitor every second.

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

ESP32 KY-035 MicroPython Code Example

Example in Micro Python Framework

Fill in this script in your MicroPython main.py file (main.py) to integrate the KY-035 Analog Hall Magnetic 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:
    raw_value = SENSOR_PIN.read()
    voltage = (raw_value / 4095) * 3300  # Convert to millivolts
    print("Magnetic Field Voltage:", voltage, "mV")
    time.sleep(1)

This MicroPython script configures GPIO34 as an ADC input for the KY-035 sensor. It reads the raw ADC value, converts it to millivolts, and prints it to the console every second.

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