Micropython on the ESP32 can be put into deepsleep.

It can be woken from deepsleep from mulitple pins using esp32.wake_on_ext1.

Unfortunately there is no way to find out which particular IO pin woke the device.

Here's a trick if you only have 2 different inputs that are going to wake the device:

Get one to wake_on_ext0, and the other to wake_on_ext1.

machine.wake_reason will then report 2 for wake_on_ext0 and 3 for wake_on_ext1

Put micropython on your controller

esptool.py --baud 115200 --port /dev/tty.SLAB_USBtoUART erase_flash
esptool.py --chip esp32 --port /dev/tty.SLAB_USBtoUART --baud 115200 write_flash 0x1000  ./esp32-idf3-20200327-v1.12-310-g9418611c8.bin

Copy the code there

ampy put ./main.py main.py

watch the output

screen /dev/tty.SLAB_USBtoUART 115200 -L