This is the v1.20.0 version of the MicroPython documentation. The latest development version of this page may be more current.

11. Power control

pyb.wfi() is used to reduce power consumption while waiting for an event such as an interrupt. You would use it in the following situation:

while True:
    do_some_processing()
    pyb.wfi()

Control the frequency using pyb.freq():

pyb.freq(30000000) # set CPU frequency to 30MHz