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micropython

The Pyboard

PWM @ 10 kHz on pins X2 and X3 in center mode

Pin X2 is 25% duty cycle, and X3 is 50% duty cycle.

import pyb

# TIM2 runs at 84 MHz
# at 20000 Hz, count runs from 0 to 4199
# In center mode, the frequency will be halved, so we'll get a 10 kHz output
t2 = pyb.Timer(2, freq=20000, counter_mode=pyb.Timer.COUNTER_MODE_CENTER)
ch2 = t2.channel(2, mode=pyb.Timer.PWM, pin=pyb.Pin.board.X2, pulse_width=((t2.period() + 1) // 4) - 1)
ch3 = t2.channel(3, mode=pyb.Timer.PWM, pin=pyb.Pin.board.X3, pulse_width=((t2.period() + 1) // 2) - 1)

This is what the signal looks like on a logic analyzer: PWM Test

OC Mode @ 1 KHz

Pin X2 is OC Mode producing a 1 KHz clock. Pin X3 is PWM at 200 Hz with a 10% duty cycle. 

import pyb

# setup oc_clock to be a 1 kHz clock. Since it toggles we want it to toggle
# 2000 times per second to get a 1000 Hz clock.
t2 = pyb.Timer(2, freq=2000)
oc  = t2.channel(2, mode=pyb.Timer.OC, pin=pyb.Pin.board.X2, oc_mode=pyb.Timer.OC_MODE_TOGGLE)

# stup PWM to be 200 Hz with a 1 clock pulse_width
t5 = pyb.Timer(5, prescaler=41999, period=9)
pwm = t5.channel(3, mode=pyb.Timer.PWM, pin=pyb.Pin.board.X3, pulse_width=1)
This is what the signal looks like on a logic analyzer: OC Test