circuitpython/ports/raspberrypi/common-hal/countio/Counter.c
2021-03-15 19:27:36 +05:30

104 lines
2.9 KiB
C

#include "common-hal/countio/Counter.h"
#include "py/runtime.h"
#include "py/mpstate.h"
#include "supervisor/shared/translate.h"
#include "common-hal/pwmio/PWMOut.h"
#include "src/rp2_common/hardware_gpio/include/hardware/gpio.h"
#include "src/rp2_common/hardware_pwm/include/hardware/pwm.h"
#include "src/rp2_common/hardware_irq/include/hardware/irq.h"
void common_hal_countio_counter_construct(countio_counter_obj_t *self,
const mcu_pin_obj_t *pin_a) {
if (pwm_gpio_to_channel(pin_a->number) != PWM_CHAN_B) {
mp_raise_RuntimeError(translate("Pin must be on PWM Channel B"));
}
self->pin_a = pin_a->number;
self->slice_num = pwm_gpio_to_slice_num(self->pin_a);
if (MP_STATE_PORT(counting)[self->slice_num] != NULL) {
mp_raise_RuntimeError(translate("PWM slice already in use"));
}
uint8_t channel = pwm_gpio_to_channel(self->pin_a);
if (!pwmio_claim_slice_channels(self->slice_num)) {
mp_raise_RuntimeError(translate("PWM slice channel A already in use"));
}
pwm_clear_irq(self->slice_num);
pwm_set_irq_enabled(self->slice_num, true);
irq_set_exclusive_handler(PWM_IRQ_WRAP, counter_interrupt_handler);
irq_set_enabled(PWM_IRQ_WRAP, true);
pwm_config cfg = pwm_get_default_config();
pwm_config_set_clkdiv_mode(&cfg, PWM_DIV_B_RISING);
pwm_init(self->slice_num, &cfg, false);
gpio_set_function(self->pin_a, GPIO_FUNC_PWM);
claim_pin(pin_a);
MP_STATE_PORT(counting)[self->slice_num] = self;
self->count = 0;
pwm_set_enabled(self->slice_num, true);
}
bool common_hal_countio_counter_deinited(countio_counter_obj_t *self) {
return self->pin_a == 0;
}
void common_hal_countio_counter_deinit(countio_counter_obj_t *self) {
if (common_hal_countio_counter_deinited(self)) {
return;
}
pwm_set_enabled(self->slice_num, false);
pwm_set_irq_enabled(self->slice_num, false);
pwmio_release_slice_channels(self->slice_num);
reset_pin_number(self->pin_a);
MP_STATE_PORT(counting)[self->slice_num] = NULL;
self->pin_a = 0;
self->slice_num = 0;
}
mp_int_t common_hal_countio_counter_get_count(countio_counter_obj_t *self) {
self->count += pwm_get_counter(self->slice_num);
pwm_set_counter(self->slice_num, 0);
return self->count;
}
void common_hal_countio_counter_set_count(countio_counter_obj_t *self,
mp_int_t new_count) {
pwm_set_counter(self->slice_num, 0);
self->count = new_count;
}
void common_hal_countio_counter_reset(countio_counter_obj_t *self) {
pwm_set_counter(self->slice_num, 0);
self->count = 0;
}
void counter_interrupt_handler() {
uint32_t mask = pwm_get_irq_status_mask();
uint8_t i = 1, pos = 1;
while (!(i & mask)) {
i = i << 1;
++pos;
}
countio_counter_obj_t *self = MP_STATE_PORT(counting)[pos - 1];
if (self != NULL) {
pwm_clear_irq(self->slice_num);
self->count += 65536;
}
}