circuitpython/shared-bindings/pulseio/PWMOut.c
2020-07-06 19:16:25 +01:00

246 lines
11 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* SPDX-FileCopyrightText: Copyright (c) 2016 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdint.h>
#include "lib/utils/context_manager_helpers.h"
#include "py/objproperty.h"
#include "py/runtime.h"
#include "shared-bindings/microcontroller/Pin.h"
#include "shared-bindings/pulseio/PWMOut.h"
#include "shared-bindings/util.h"
#include "supervisor/shared/translate.h"
//| class PWMOut:
//| """Output a Pulse Width Modulated signal on a given pin."""
//|
//| def __init__(self, pin: microcontroller.Pin, *, duty_cycle: int = 0, frequency: int = 500, variable_frequency: bool = False):
//| """Create a PWM object associated with the given pin. This allows you to
//| write PWM signals out on the given pin. Frequency is fixed after init
//| unless ``variable_frequency`` is True.
//|
//| .. note:: When ``variable_frequency`` is True, further PWM outputs may be
//| limited because it may take more internal resources to be flexible. So,
//| when outputting both fixed and flexible frequency signals construct the
//| fixed outputs first.
//|
//| :param ~microcontroller.Pin pin: The pin to output to
//| :param int duty_cycle: The fraction of each pulse which is high. 16-bit
//| :param int frequency: The target frequency in Hertz (32-bit)
//| :param bool variable_frequency: True if the frequency will change over time
//|
//| Simple LED fade::
//|
//| import pulseio
//| import board
//|
//| pwm = pulseio.PWMOut(board.D13) # output on D13
//| pwm.duty_cycle = 2 ** 15 # Cycles the pin with 50% duty cycle (half of 2 ** 16) at the default 500hz
//|
//| PWM at specific frequency (servos and motors)::
//|
//| import pulseio
//| import board
//|
//| pwm = pulseio.PWMOut(board.D13, frequency=50)
//| pwm.duty_cycle = 2 ** 15 # Cycles the pin with 50% duty cycle (half of 2 ** 16) at 50hz
//|
//| Variable frequency (usually tones)::
//|
//| import pulseio
//| import board
//| import time
//|
//| pwm = pulseio.PWMOut(board.D13, duty_cycle=2 ** 15, frequency=440, variable_frequency=True)
//| time.sleep(0.2)
//| pwm.frequency = 880
//| time.sleep(0.1)"""
//| ...
//|
STATIC mp_obj_t pulseio_pwmout_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
enum { ARG_pin, ARG_duty_cycle, ARG_frequency, ARG_variable_frequency };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_pin, MP_ARG_REQUIRED | MP_ARG_OBJ, },
{ MP_QSTR_duty_cycle, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
{ MP_QSTR_frequency, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 500} },
{ MP_QSTR_variable_frequency, MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
};
mp_arg_val_t parsed_args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args, args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, parsed_args);
const mcu_pin_obj_t *pin = validate_obj_is_free_pin(parsed_args[ARG_pin].u_obj);
uint16_t duty_cycle = parsed_args[ARG_duty_cycle].u_int;
uint32_t frequency = parsed_args[ARG_frequency].u_int;
bool variable_frequency = parsed_args[ARG_variable_frequency].u_bool;
// create PWM object from the given pin
pulseio_pwmout_obj_t *self = m_new_obj(pulseio_pwmout_obj_t);
self->base.type = &pulseio_pwmout_type;
pwmout_result_t result = common_hal_pulseio_pwmout_construct(self, pin, duty_cycle, frequency, variable_frequency);
if (result == PWMOUT_INVALID_PIN) {
mp_raise_ValueError(translate("Invalid pin"));
} else if (result == PWMOUT_INVALID_FREQUENCY) {
mp_raise_ValueError(translate("Invalid PWM frequency"));
} else if (result == PWMOUT_ALL_TIMERS_ON_PIN_IN_USE) {
mp_raise_ValueError(translate("All timers for this pin are in use"));
} else if (result == PWMOUT_ALL_TIMERS_IN_USE) {
mp_raise_RuntimeError(translate("All timers in use"));
}
return MP_OBJ_FROM_PTR(self);
}
//| def deinit(self, ) -> Any:
//| """Deinitialises the PWMOut and releases any hardware resources for reuse."""
//| ...
//|
STATIC mp_obj_t pulseio_pwmout_deinit(mp_obj_t self_in) {
pulseio_pwmout_obj_t *self = MP_OBJ_TO_PTR(self_in);
common_hal_pulseio_pwmout_deinit(self);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(pulseio_pwmout_deinit_obj, pulseio_pwmout_deinit);
STATIC void check_for_deinit(pulseio_pwmout_obj_t *self) {
if (common_hal_pulseio_pwmout_deinited(self)) {
raise_deinited_error();
}
}
//| def __enter__(self, ) -> Any:
//| """No-op used by Context Managers."""
//| ...
//|
// Provided by context manager helper.
//| def __exit__(self, ) -> Any:
//| """Automatically deinitializes the hardware when exiting a context. See
//| :ref:`lifetime-and-contextmanagers` for more info."""
//| ...
//|
STATIC mp_obj_t pulseio_pwmout_obj___exit__(size_t n_args, const mp_obj_t *args) {
(void)n_args;
common_hal_pulseio_pwmout_deinit(args[0]);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pulseio_pwmout___exit___obj, 4, 4, pulseio_pwmout_obj___exit__);
//| duty_cycle: Any = ...
//| """16 bit value that dictates how much of one cycle is high (1) versus low
//| (0). 0xffff will always be high, 0 will always be low and 0x7fff will
//| be half high and then half low.
//|
//| Depending on how PWM is implemented on a specific board, the internal
//| representation for duty cycle might have less than 16 bits of resolution.
//| Reading this property will return the value from the internal representation,
//| so it may differ from the value set."""
//|
STATIC mp_obj_t pulseio_pwmout_obj_get_duty_cycle(mp_obj_t self_in) {
pulseio_pwmout_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
return MP_OBJ_NEW_SMALL_INT(common_hal_pulseio_pwmout_get_duty_cycle(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(pulseio_pwmout_get_duty_cycle_obj, pulseio_pwmout_obj_get_duty_cycle);
STATIC mp_obj_t pulseio_pwmout_obj_set_duty_cycle(mp_obj_t self_in, mp_obj_t duty_cycle) {
pulseio_pwmout_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
mp_int_t duty = mp_obj_get_int(duty_cycle);
if (duty < 0 || duty > 0xffff) {
mp_raise_ValueError(translate("PWM duty_cycle must be between 0 and 65535 inclusive (16 bit resolution)"));
}
common_hal_pulseio_pwmout_set_duty_cycle(self, duty);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(pulseio_pwmout_set_duty_cycle_obj, pulseio_pwmout_obj_set_duty_cycle);
const mp_obj_property_t pulseio_pwmout_duty_cycle_obj = {
.base.type = &mp_type_property,
.proxy = {(mp_obj_t)&pulseio_pwmout_get_duty_cycle_obj,
(mp_obj_t)&pulseio_pwmout_set_duty_cycle_obj,
(mp_obj_t)&mp_const_none_obj},
};
//| frequency: Any = ...
//| """32 bit value that dictates the PWM frequency in Hertz (cycles per
//| second). Only writeable when constructed with ``variable_frequency=True``.
//|
//| Depending on how PWM is implemented on a specific board, the internal value
//| 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."""
//|
STATIC mp_obj_t pulseio_pwmout_obj_get_frequency(mp_obj_t self_in) {
pulseio_pwmout_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
return MP_OBJ_NEW_SMALL_INT(common_hal_pulseio_pwmout_get_frequency(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(pulseio_pwmout_get_frequency_obj, pulseio_pwmout_obj_get_frequency);
STATIC mp_obj_t pulseio_pwmout_obj_set_frequency(mp_obj_t self_in, mp_obj_t frequency) {
pulseio_pwmout_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
if (!common_hal_pulseio_pwmout_get_variable_frequency(self)) {
mp_raise_AttributeError(translate(
"PWM frequency not writable when variable_frequency is False on "
"construction."));
}
common_hal_pulseio_pwmout_set_frequency(self, mp_obj_get_int(frequency));
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(pulseio_pwmout_set_frequency_obj, pulseio_pwmout_obj_set_frequency);
const mp_obj_property_t pulseio_pwmout_frequency_obj = {
.base.type = &mp_type_property,
.proxy = {(mp_obj_t)&pulseio_pwmout_get_frequency_obj,
(mp_obj_t)&pulseio_pwmout_set_frequency_obj,
(mp_obj_t)&mp_const_none_obj},
};
STATIC const mp_rom_map_elem_t pulseio_pwmout_locals_dict_table[] = {
// Methods
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&pulseio_pwmout_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) },
{ MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&pulseio_pwmout___exit___obj) },
// Properties
{ MP_ROM_QSTR(MP_QSTR_duty_cycle), MP_ROM_PTR(&pulseio_pwmout_duty_cycle_obj) },
{ MP_ROM_QSTR(MP_QSTR_frequency), MP_ROM_PTR(&pulseio_pwmout_frequency_obj) },
// TODO(tannewt): Add enabled to determine whether the signal is output
// without giving up the resources. Useful for IR output.
};
STATIC MP_DEFINE_CONST_DICT(pulseio_pwmout_locals_dict, pulseio_pwmout_locals_dict_table);
const mp_obj_type_t pulseio_pwmout_type = {
{ &mp_type_type },
.name = MP_QSTR_PWMOut,
.make_new = pulseio_pwmout_make_new,
.locals_dict = (mp_obj_dict_t*)&pulseio_pwmout_locals_dict,
};