ESP32 ULP Wake-up from Hall Sensor

In this short example, we'll wake the ESP32 up using readings from the internal hall sensor, according to a threshold.

This was based on the code from esp-iot-solution example.

Let's do it!

First you've got to build your sdkconfig file:

make menuconfig

Go through "Component config" > "ESP32-specific" and enable "Enable Ultra Low Power (ULP) Coprocessor", setting "RTC slow memory reserver for coprocessor" as 1024. Save it and then press Esc+Esc few times in order to exit.

After that, just do:

make flash monitor

And this code will be flashed into the ESP32 and serial monitor will open on your screen. Be happy!

Changing threshold value

You just have to edit the ".set threshold, 70" line on hall_sensor.S to your desired value!