Wake machine.deepsleep using pin input from accelerometer [SOLVED]

  • I'm trying to create an accelerometer interrupt for machine.deepsleep(). From what I can tell there is no built-in function for that. Since deep sleep can be interrupted with a pin I was thinking that there might be a pin that allows the accelerometer to relay an interrupt to the device.

    I've tried P13, which is denoted as "Accelerometer Interrupt" on the Pytrack pinout but I didn't get a response (even when the device was not asleep). Here is the code I was using

    from machine import Pin
    def pin_handler(arg):
        print("got an interrupt in pin %s" % (arg.id()))
    p_in = Pin('P13', mode=Pin.IN, pull=Pin.PULL_UP) 
    p_in.callback(Pin.IRQ_FALLING, pin_handler)

    Any ideas or suggestions would be great!

    My system specs:

    (sysname='WiPy', nodename='WiPy', release='1.18.0.r1', version='v1.8.6-849-9569a73 on 2018-07-20', machine='WiPy with ESP32', pybytes='0.9.0')

  • Ah ha. I was using the wrong interrupt script.

    This is the correct working code for an accelerometer interrupt (P13) of machine.deepsleep():

    import machine
    machine.pin_deepsleep_wakeup(['P13'], machine.WAKEUP_ANY_HIGH, False)

    So for pin interrupts there is a callback() function to create interrupts of active and sleep modes but the pin_deepsleep_wakeup() is needed to interrupt deep sleep (is that what you meant by "wake-on-pin" @jcaron?). There is no interrupt handler for pin_deepsleep_wakeup() because the working memory is cleared after deep sleep (as mentioned by @jcaron below).

    @jcaron I had tested my interrupt handler without sleep and it did work. In my main.py I had the following script to test that it woke from deep sleep and ran main.py.

    import pycom
    import utime
    pycom.heartbeat(False)                      #turn off LED
    pycom.rgbled(0xFF0000)                    #red LED
    pycom.heartbeat(False)                      #turn off LED

  • @alexpul In that code you don't enable wake-on-pin, and you don't do anything visible before going back to sleep, so even if it wakes up you won't see anything...

    Note that as far as I know, the handler will only be called if the interrupt happens while the device is awake, not during sleep.

    Start by using acc.enable_activity_interrupt without any deep sleep to see if the interrupt gets triggered (i.e. just remove the machine.deepsleep in your code).

    Once you have confirmed that, you can add the wake-on-pin, and do something visible when you wake up before going back to sleep.

  • @jcaron This is the code I've tried to test if the accelerometer can wake from machine.deepsleep()

    from LIS2HH12 import LIS2HH12
    import pycom
    import machine
    import utime
    def accel_activity_handler(pin_o):
    acc = LIS2HH12()
    acc.enable_activity_interrupt(1000, 200, handler=accel_activity_handler)

    When I shake the device nothing happens...

    (Note that this script does allow for a deep sleep interrupt but only when pytrack.go_to_sleep() is used to enter deep sleep. I need to use machine.deepsleep() though..)

  • @alexpul Did you configure the accelerometer (enable it, set it to monitor events and send interrupts)?

    You need to at least instantiate the LIS2HH12 class, and call the enable_activity_interrupt method.

    There may be more stuff to do. Check the sources of the PyTrack library for more information.

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