LoPy4 alarm callback not repeating periodically

  • I have a LoPy4 which I am trying to measure an ADC voltage on periodically. I have an alarm that I am trying to trigger interrupts every five seconds with. Here is what the code I am testing with looks like:

    from machine import ADC
    from machine import Timer
    import utime
    adc = ADC(0)
    #ADC channels for baterry voltage monitoring
    adc_b1 = adc.channel(pin = 'P20', attn=ADC.ATTN_11DB)
    list = []
    #Measures battery voltage
    def battery_voltage():
        for i in range(0, 35):
            read = adc_b1.voltage()
            list.insert(i, read)
        avg_reading_b1 = sum(list)/len(list)
        bat_1 = str(round(avg_reading_b1/1000, 2)) #String and round
    battery_alarm = Timer.Alarm(battery_voltage(), s=5, periodic=True)
    def main():

    The functions battery_voltage() gets called once after the file has been successfully uploaded. After that, the program continues to loop but battery_voltage() does not get called again. Is there something wrong with how I am setting up the alarm?

  • @joshhulnz
    a) write: Timer.Alarm(battery_voltage, s=5, periodic=True) without the brackets.
    b) in the main loop, I would use a short sleep instead of the continue statement
    c) I you just need the average, you do not have to collect the values. Just add them up while reading, e.g.

    def battery_voltage():
        avg = 0
        for i in range(0, 35):
            avg += adc_b1.voltage()
        print(round(avg/35000, 2))

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