diff options
| author | chrismas9 <c.mason@inchipdesign.com.au> | 2022-06-26 23:54:37 +1000 |
|---|---|---|
| committer | Damien George <damien@micropython.org> | 2022-07-29 12:22:23 +1000 |
| commit | c038ea0cc68bff18ce9ac338a283d2dd4cf29f1e (patch) | |
| tree | 6047c5d2d7da1e64667be68638f6db445df85e61 /docs/library/pyb.Timer.rst | |
| parent | 33ea400ce849777617bf1e8f44b10928530b64b9 (diff) | |
docs/library/pyb.Timer: Document how to use BKIN pin with example.
Document how to connect the Timer block BRK_IN to a physical Pin alternate
function.
Add an example of PWM Motor drive using complementary outputs with dead
time and break input to kill the PWM and generate a callback.
Signed-off-by: Chris Mason <c.mason@inchipdesign.com.au>
Diffstat (limited to 'docs/library/pyb.Timer.rst')
| -rw-r--r-- | docs/library/pyb.Timer.rst | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/docs/library/pyb.Timer.rst b/docs/library/pyb.Timer.rst index 53213666b..1749efce2 100644 --- a/docs/library/pyb.Timer.rst +++ b/docs/library/pyb.Timer.rst @@ -111,7 +111,9 @@ Methods the PWM when the ``BRK_IN`` input is asserted. The value of this argument determines if break is enabled and what the polarity is, and can be one of ``Timer.BRK_OFF``, ``Timer.BRK_LOW`` or - ``Timer.BRK_HIGH``. + ``Timer.BRK_HIGH``. To select the ``BRK_IN`` pin construct a Pin object with + ``mode=Pin.ALT, alt=Pin.AFn_TIMx``. The pin's GPIO input features are + available in alt mode - ``pull=`` , ``value()`` and ``irq()``. You must either specify freq or both of period and prescaler. @@ -204,6 +206,17 @@ Methods ch2 = timer.channel(2, pyb.Timer.PWM, pin=pyb.Pin.board.X2, pulse_width=8000) ch3 = timer.channel(3, pyb.Timer.PWM, pin=pyb.Pin.board.X3, pulse_width=16000) + PWM Motor Example with complementary outputs, dead time, break input and break callback:: + + from pyb import Timer + from machine import Pin # machine.Pin supports alt mode and irq on the same pin. + pin_t8_1 = Pin(Pin.board.Y1, mode=Pin.ALT, af=Pin.AF3_TIM8) # Pin PC6, TIM8_CH1 + pin_t8_1n = Pin(Pin.board.X8, mode=Pin.ALT, af=Pin.AF3_TIM8) # Pin PA7, TIM8_CH1N + pin_bkin = Pin(Pin.board.X7, mode=Pin.ALT, af=Pin.AF3_TIM8) # Pin PA6, TIM8_BKIN + pin_bkin.irq(handler=break_callabck, trigger=Pin.IRQ_FALLING) + timer = pyb.Timer(8, freq=1000, deadtime=1008, brk=Timer.BRK_LOW) + ch1 = timer.channel(1, pyb.Timer.PWM, pulse_width_percent=30) + .. method:: Timer.counter([value]) Get or set the timer counter. |