circuitpython/shared-bindings/pulseio/PWMOut.c
Scott Shawcroft f28f8ba568 Split up nativeio.
This was done to allow greatly granularity when deciding what functionality
is built into each board's build. For example, this way pulseio can be
omitted to allow for something else such as touchio.
2017-04-10 13:32:19 -07:00

222 lines
9.1 KiB
C

/*
* This file is part of the Micro Python project, http://micropython.org/
*
* The MIT License (MIT)
*
* 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"
//| .. currentmodule:: pulseio
//|
//| :class:`PWMOut` -- Output a Pulse Width Modulated signal
//| ========================================================
//|
//| PWMOut can be used to output a PWM signal on a given pin.
//|
//| .. class:: PWMOut(pin, \*, duty_cycle=0, frequency=500, variable_frequency=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: 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
//|
//| with pulseio.PWMOut(board.D13) as pwm: # 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
//|
//| with pulseio.PWMOut(board.D13, frequency=50) as pwm:
//| 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
//|
//| with pulseio.PWMOut(board.D13, duty_cycle=2 ** 15, frequency=440, variable_frequency=True) as pwm:
//| 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, size_t n_kw, const mp_obj_t *args) {
mp_arg_check_num(n_args, n_kw, 1, MP_OBJ_FUN_ARGS_MAX, true);
mp_obj_t pin_obj = args[0];
assert_pin(pin_obj, false);
const mcu_pin_obj_t *pin = MP_OBJ_TO_PTR(pin_obj);
assert_pin_free(pin);
// 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;
mp_map_t kw_args;
mp_map_init_fixed_table(&kw_args, n_kw, args + n_args);
enum { ARG_duty_cycle, ARG_frequency, ARG_variable_frequency };
static const mp_arg_t allowed_args[] = {
{ 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 - 1, args + 1, &kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, parsed_args);
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_int;
common_hal_pulseio_pwmout_construct(self, pin, duty_cycle, frequency, variable_frequency);
return MP_OBJ_FROM_PTR(self);
}
//| .. method:: deinit()
//|
//| 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);
//| .. method:: __enter__()
//|
//| No-op used by Context Managers.
//|
// Provided by context manager helper.
//| .. method:: __exit__()
//|
//| Automatically deinitializes the hardware when exiting a context.
//|
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__);
//| .. attribute:: duty_cycle
//|
//| 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.
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);
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);
mp_int_t duty = mp_obj_get_int(duty_cycle);
if (duty < 0 || duty > 0xffff) {
mp_raise_ValueError("PWM duty must be between 0 and 65536 (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},
};
//| .. attribute:: frequency
//|
//| 32 bit value that dictates the PWM frequency in Hertz (cycles per
//| second). Only writeable when constructed with ``variable_frequency=True``.
//|
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);
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);
if (!common_hal_pulseio_pwmout_get_variable_frequency(self)) {
mp_raise_AttributeError(
"PWM frequency not writeable 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,
};