I read that ESP32 has pins 36 and 39 to read analog using external hall effect sensor. Could you please explain how to connect external hall effect sensor to ESP32 and how to read its value and how we expose it to a magnet?
Thanks a lot in advance.
I’m not really sure if I understood your question.
You want to connect an external hall effect sensor to the ESP32? Can you tell me which hall effect sensor you’d like to use?
Or are you talking about the internal hall effect sensor? If you’re talking about the internal hall effect sensor, there’s a dedicated unit in the ESP32 course about that – Module 2, Unit 5: https://rntlab.com/module-2/esp32-hall-effect-sensor/
what I meant is that I want to use an external hall effect sensor with ESP32 (say A3144). How do I wire an external hall effect sensor to ESP32 and how do I read it in the code?
Thanks a lot in advance for any help.
I’ve never used that sensor. But as it is an analog sensor that spits ou an analog signal proportional to the magnetic field, you just need to wire the data pin to one of the ESP32 analog pins. It can be any analog pin. Not just GPIOs 36 or 39.
Because the sensor needs at least 4.5V to operate (accordingly to the datasheet), you may need to add a voltage divider circuit depending on the values you’ll get.
Then, you can read it in your code as you read the value from a potentiometer. If you use a voltage divider circuit, then you need to map your readings.
I’ve read that the sensor readings from that sensor oscillate a bit and it is better to take readings several times and then calculate the average value.
I hope this helps.