using lambda with timer

[AlexBir]

Hi,

Code: Select all

def blink_led():
    pyb.LED(1).toggle()



tim=pyb.Timer(4)
tim.init(freq=2)
tim.callback(blink_led)

I am getting:


PYB: sync filesystems
PYB: soft reboot
MicroPython v1.9.4-85-gdf9b7e8f on 2018-05-24; PYBv1.1 with STM32F405RG
Type "help()" for more information.
>>> uncaught exception in Timer(4) interrupt handler
TypeError:



why?

[dhylands]

Because your callback is missing a parameter.

The documentation for the timer callback is here:
http://docs.micropython.org/en/latest/l ... l.callback
Your callback must take one argument, which is the timer object.

You can also use lambda functions like this example here:
http://docs.micropython.org/en/latest/p ... -callbacks
which takes one argument (the t)

You can also get more information about the error by allocating an emergency exception buffer as described here:
http://docs.micropython.org/en/latest/r ... ion-buffer