circuitpython/ports/nrf/modules/machine/pwm.c

351 lines
12 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016-2018 Glenn Ruben Bakke
*
* 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 <stdio.h>
#include <string.h>
#include "py/nlr.h"
#include "py/runtime.h"
#include "py/mphal.h"
#if MICROPY_PY_MACHINE_HW_PWM
#include "pin.h"
#include "genhdr/pins.h"
#include "pwm.h"
#if defined(NRF52_SERIES)
// Use PWM hardware.
#include "nrfx_pwm.h"
#endif
typedef enum {
MODE_LOW_HIGH,
MODE_HIGH_LOW
} pwm_mode_t;
typedef struct {
uint8_t pwm_pin;
uint8_t duty;
uint16_t pulse_width;
uint16_t period;
nrf_pwm_clk_t freq;
pwm_mode_t mode;
} machine_pwm_config_t;
typedef struct _machine_hard_pwm_obj_t {
mp_obj_base_t base;
const nrfx_pwm_t * p_pwm;
machine_pwm_config_t * p_config;
} machine_hard_pwm_obj_t;
STATIC const nrfx_pwm_t machine_hard_pwm_instances[] = {
#if defined(NRF52_SERIES)
NRFX_PWM_INSTANCE(0),
NRFX_PWM_INSTANCE(1),
NRFX_PWM_INSTANCE(2),
#if NRF52840
NRFX_PWM_INSTANCE(3),
#endif
#endif
};
STATIC machine_pwm_config_t hard_configs[MP_ARRAY_SIZE(machine_hard_pwm_instances)];
STATIC const machine_hard_pwm_obj_t machine_hard_pwm_obj[] = {
#if defined(NRF52_SERIES)
{{&machine_hard_pwm_type}, .p_pwm = &machine_hard_pwm_instances[0], .p_config = &hard_configs[0]},
{{&machine_hard_pwm_type}, .p_pwm = &machine_hard_pwm_instances[1], .p_config = &hard_configs[1]},
{{&machine_hard_pwm_type}, .p_pwm = &machine_hard_pwm_instances[2], .p_config = &hard_configs[2]},
#if NRF52840
{{&machine_hard_pwm_type}, .p_pwm = &machine_hard_pwm_instances[3], .p_config = &hard_configs[3]},
#endif
#endif
};
void pwm_init0(void) {
}
STATIC int hard_pwm_find(mp_obj_t id) {
if (mp_obj_is_int(id)) {
// given an integer id
int pwm_id = mp_obj_get_int(id);
if (pwm_id >= 0 && pwm_id < MP_ARRAY_SIZE(machine_hard_pwm_obj)) {
return pwm_id;
}
mp_raise_ValueError(MP_ERROR_TEXT("PWM doesn't exist"));
}
return -1;
}
STATIC void machine_pwm_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
machine_hard_pwm_obj_t *self = self_in;
mp_printf(print, "PWM(%u)", self->p_pwm->drv_inst_idx);
}
/******************************************************************************/
/* MicroPython bindings for machine API */
STATIC mp_obj_t machine_hard_pwm_make_new(mp_arg_val_t *args);
STATIC void machine_hard_pwm_init(mp_obj_t self, mp_arg_val_t *args);
STATIC void machine_hard_pwm_deinit(mp_obj_t self);
STATIC mp_obj_t machine_hard_pwm_freq(mp_obj_t self, mp_arg_val_t *args);
/* common code for both soft and hard implementations *************************/
STATIC mp_obj_t machine_pwm_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
enum { ARG_id, ARG_pin, ARG_freq, ARG_period, ARG_duty, ARG_pulse_width, ARG_mode };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_id, MP_ARG_OBJ, {.u_obj = MP_OBJ_NEW_SMALL_INT(-1)} },
{ MP_QSTR_pin, MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_freq, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_period, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_duty, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_pulse_width, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
{ MP_QSTR_mode, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
};
// parse args
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
if (args[ARG_id].u_obj == MP_OBJ_NEW_SMALL_INT(-1)) {
// TODO: implement soft PWM
// return machine_soft_pwm_make_new(args);
return mp_const_none;
} else {
// hardware peripheral id given
return machine_hard_pwm_make_new(args);
}
}
STATIC mp_obj_t machine_pwm_init(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
enum { ARG_INIT_pin };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_pin, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }
};
// parse args
mp_obj_t self = pos_args[0];
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
// dispatch to specific implementation
if (mp_obj_get_type(self) == &machine_hard_pwm_type) {
machine_hard_pwm_init(self, args);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(machine_pwm_init_obj, 1, machine_pwm_init);
STATIC mp_obj_t machine_pwm_deinit(mp_obj_t self) {
// dispatch to specific implementation
if (mp_obj_get_type(self) == &machine_hard_pwm_type) {
machine_hard_pwm_deinit(self);
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_pwm_deinit_obj, machine_pwm_deinit);
STATIC mp_obj_t machine_pwm_freq(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
enum { ARG_FREQ_freq };
static const mp_arg_t allowed_args[] = {
{ MP_QSTR_freq, MP_ARG_INT, {.u_int = -1} },
};
mp_obj_t self = pos_args[0];
mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
if (mp_obj_get_type(self) == &machine_hard_pwm_type) {
machine_hard_pwm_freq(self, args);
} else {
// soft pwm
}
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mp_machine_pwm_freq_obj, 1, machine_pwm_freq);
STATIC mp_obj_t machine_pwm_period(size_t n_args, const mp_obj_t *args) {
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_pwm_period_obj, 1, 2, machine_pwm_period);
STATIC mp_obj_t machine_pwm_duty(size_t n_args, const mp_obj_t *args) {
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_pwm_duty_obj, 1, 2, machine_pwm_duty);
STATIC const mp_rom_map_elem_t machine_pwm_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&machine_pwm_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&machine_pwm_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR_freq), MP_ROM_PTR(&mp_machine_pwm_freq_obj) },
{ MP_ROM_QSTR(MP_QSTR_period), MP_ROM_PTR(&mp_machine_pwm_period_obj) },
{ MP_ROM_QSTR(MP_QSTR_duty), MP_ROM_PTR(&mp_machine_pwm_duty_obj) },
{ MP_ROM_QSTR(MP_QSTR_FREQ_16MHZ), MP_ROM_INT(NRF_PWM_CLK_16MHz) },
{ MP_ROM_QSTR(MP_QSTR_FREQ_8MHZ), MP_ROM_INT(NRF_PWM_CLK_8MHz) },
{ MP_ROM_QSTR(MP_QSTR_FREQ_4MHZ), MP_ROM_INT(NRF_PWM_CLK_4MHz) },
{ MP_ROM_QSTR(MP_QSTR_FREQ_2MHZ), MP_ROM_INT(NRF_PWM_CLK_2MHz) },
{ MP_ROM_QSTR(MP_QSTR_FREQ_1MHZ), MP_ROM_INT(NRF_PWM_CLK_1MHz) },
{ MP_ROM_QSTR(MP_QSTR_FREQ_500KHZ), MP_ROM_INT(NRF_PWM_CLK_500kHz) },
{ MP_ROM_QSTR(MP_QSTR_FREQ_250KHZ), MP_ROM_INT(NRF_PWM_CLK_250kHz) },
{ MP_ROM_QSTR(MP_QSTR_FREQ_125KHZ), MP_ROM_INT(NRF_PWM_CLK_125kHz) },
{ MP_ROM_QSTR(MP_QSTR_MODE_LOW_HIGH), MP_ROM_INT(MODE_LOW_HIGH) },
{ MP_ROM_QSTR(MP_QSTR_MODE_HIGH_LOW), MP_ROM_INT(MODE_HIGH_LOW) },
};
STATIC MP_DEFINE_CONST_DICT(machine_pwm_locals_dict, machine_pwm_locals_dict_table);
/* code for hard implementation ***********************************************/
STATIC mp_obj_t machine_hard_pwm_make_new(mp_arg_val_t *args) {
enum { ARG_id, ARG_pin, ARG_freq, ARG_period, ARG_duty, ARG_pulse_width, ARG_mode };
// get static peripheral object
int pwm_id = hard_pwm_find(args[ARG_id].u_obj);
const machine_hard_pwm_obj_t *self = &machine_hard_pwm_obj[pwm_id];
// check if PWM pin is set
if (args[ARG_pin].u_obj != MP_OBJ_NULL) {
self->p_config->pwm_pin = mp_hal_get_pin_obj(args[ARG_pin].u_obj)->pin;
} else {
// TODO: raise exception.
}
if (args[ARG_freq].u_obj != MP_OBJ_NULL) {
self->p_config->freq = mp_obj_get_int(args[ARG_freq].u_obj);
} else {
self->p_config->freq = 50; // 50 Hz by default.
}
if (args[ARG_period].u_obj != MP_OBJ_NULL) {
self->p_config->period = mp_obj_get_int(args[ARG_period].u_obj);
} else {
mp_raise_ValueError(MP_ERROR_TEXT("PWM period must be within 16000 cycles"));
}
if (args[ARG_duty].u_obj != MP_OBJ_NULL) {
self->p_config->duty = mp_obj_get_int(args[ARG_duty].u_obj);
} else {
self->p_config->duty = 50; // 50% by default.
}
if (args[ARG_pulse_width].u_obj != MP_OBJ_NULL) {
self->p_config->pulse_width = mp_obj_get_int(args[ARG_pulse_width].u_obj);
} else {
self->p_config->pulse_width = 0;
}
if (args[ARG_mode].u_obj != MP_OBJ_NULL) {
self->p_config->mode = mp_obj_get_int(args[ARG_mode].u_obj);
} else {
self->p_config->mode = MODE_HIGH_LOW;
}
return MP_OBJ_FROM_PTR(self);
}
STATIC void machine_hard_pwm_init(mp_obj_t self_in, mp_arg_val_t *args) {
machine_hard_pwm_obj_t *self = self_in;
nrfx_pwm_config_t config;
config.output_pins[0] = self->p_config->pwm_pin;
config.output_pins[1] = NRFX_PWM_PIN_NOT_USED;
config.output_pins[2] = NRFX_PWM_PIN_NOT_USED;
config.output_pins[3] = NRFX_PWM_PIN_NOT_USED;
config.irq_priority = 6;
config.base_clock = self->p_config->freq;
config.count_mode = NRF_PWM_MODE_UP;
config.top_value = self->p_config->period;
config.load_mode = NRF_PWM_LOAD_INDIVIDUAL;
config.step_mode = NRF_PWM_STEP_AUTO;
nrfx_pwm_init(self->p_pwm, &config, NULL, NULL);
uint16_t pulse_width = ((self->p_config->period * self->p_config->duty) / 100);
// If manual period has been set, override duty-cycle.
if (self->p_config->pulse_width > 0) {
pulse_width = self->p_config->pulse_width;
}
// TODO: Move DMA buffer to global memory.
volatile static uint16_t pwm_seq[4];
if (self->p_config->mode == MODE_HIGH_LOW) {
pwm_seq[0] = self->p_config->period - pulse_width;
pwm_seq[1] = self->p_config->period - pulse_width;
} else {
pwm_seq[0] = self->p_config->period - pulse_width;
pwm_seq[1] = self->p_config->period - pulse_width;
}
pwm_seq[2] = self->p_config->period - pulse_width;
pwm_seq[3] = self->p_config->period - pulse_width;
const nrf_pwm_sequence_t pwm_sequence = {
.values.p_raw = (const uint16_t *)&pwm_seq,
.length = 4,
.repeats = 0,
.end_delay = 0
};
nrfx_pwm_simple_playback(self->p_pwm,
&pwm_sequence,
0, // Loop disabled.
0);
}
STATIC void machine_hard_pwm_deinit(mp_obj_t self_in) {
machine_hard_pwm_obj_t *self = self_in;
(void)self;
nrfx_pwm_stop(self->p_pwm, true);
nrfx_pwm_uninit(self->p_pwm);
}
STATIC mp_obj_t machine_hard_pwm_freq(mp_obj_t self_in, mp_arg_val_t *args) {
machine_hard_pwm_obj_t *self = self_in;
(void)self;
return mp_const_none;
}
const mp_obj_type_t machine_hard_pwm_type = {
{ &mp_type_type },
.name = MP_QSTR_PWM,
.print = machine_pwm_print,
.make_new = machine_pwm_make_new,
.locals_dict = (mp_obj_dict_t*)&machine_pwm_locals_dict,
};
#endif // MICROPY_PY_MACHINE_HW_PWM