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Merge pull request #7649 from jepler/improve-pwmio-documentation

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Improve pwmio documentation
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Dan Halbert 2023-02-25 21:35:06 -05:00 committed by GitHub
commit f214d6b336
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1 changed files with 26 additions and 3 deletions
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29
shared-bindings/pwmio/PWMOut.c
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@ -69,7 +69,27 @@ void common_hal_pwmio_pwmout_raise_error(pwmout_result_t result) {
}
//| class PWMOut:
//| """Output a Pulse Width Modulated signal on a given pin."""
//| """Output a Pulse Width Modulated signal on a given pin.
//|
//| .. note:: The exact frequencies possible depend on the specific microcontroller.
//| If the requested frequency is within the available range, one of the two
//| nearest possible frequencies to the requested one is selected.
//|
//| If the requested frequency is outside the range, either (A) a ValueError
//| may be raised or (B) the highest or lowest frequency is selected. This
//| behavior is microcontroller-dependent, and may depend on whether it's the
//| upper or lower bound that is exceeded.
//|
//| In any case, the actual frequency (rounded to 1Hz) is available in the
//| ``frequency`` property after construction.
//|
//| .. note:: The frequency is calculated based on a nominal CPU frequency.
//| However, depending on the board, the error between the nominal and
//| actual CPU frequency can be large (several hundred PPM in the case of
//| crystal oscillators and up to ten percent in the case of RC
//| oscillators)
//|
//| """
//|
//| def __init__(
//| self,
@ -134,7 +154,9 @@ void common_hal_pwmio_pwmout_raise_error(pwmout_result_t result) {
//| pwm = pwmio.PWMOut(board.D13, duty_cycle=2 ** 15, frequency=440, variable_frequency=True)
//| time.sleep(0.2)
//| pwm.frequency = 880
//| time.sleep(0.1)"""
//| time.sleep(0.1)
//|
//| """
//| ...
STATIC mp_obj_t pwmio_pwmout_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
enum { ARG_pin, ARG_duty_cycle, ARG_frequency, ARG_variable_frequency };
@ -234,7 +256,8 @@ MP_PROPERTY_GETSET(pwmio_pwmout_duty_cycle_obj,
//| for the PWM's duty cycle may need to be recalculated when the frequency
//| changes. In these cases, the duty cycle is automatically recalculated
//| from the original duty cycle value. This should happen without any need
//| to manually re-set the duty cycle."""
//| to manually re-set the duty cycle. However, an output glitch may occur during the adjustment.
//| """
//|
STATIC mp_obj_t pwmio_pwmout_obj_get_frequency(mp_obj_t self_in) {
pwmio_pwmout_obj_t *self = MP_OBJ_TO_PTR(self_in);