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add pcnt overflow handler & clean-up

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microDev 2020-11-16 23:32:22 +05:30
parent f2824f6a68
commit 18e463cca5
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GPG Key ID: 2C0867BE60967730
2 changed files with 57 additions and 37 deletions
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91
ports/esp32s2/common-hal/frequencyio/FrequencyIn.c
View File

@ -26,16 +26,21 @@
#include "shared-bindings/frequencyio/FrequencyIn.h"
#include <stdint.h>
#include "py/runtime.h"
#include "supervisor/shared/tick.h"
#include "shared-bindings/time/__init__.h"
static void IRAM_ATTR pcnt_overflow_handler(void *self_in) {
frequencyio_frequencyin_obj_t* self = self_in;
// reset counter
pcnt_counter_clear(self->unit);
#include "common-hal/microcontroller/Pin.h"
// increase multiplier
self->multiplier++;
static void IRAM_ATTR frequencyin_interrupt_handler(void *self_in) {
// reset interrupt
PCNT.int_clr.val = BIT(self->unit);
}
static void IRAM_ATTR timer_interrupt_handler(void *self_in) {
frequencyio_frequencyin_obj_t* self = self_in;
// get counter value
int16_t count;
@ -50,9 +55,41 @@ static void IRAM_ATTR frequencyin_interrupt_handler(void *self_in) {
TIMERG0.hw_timer[0].config.alarm_en = 1;
}
static void init_timer(frequencyio_frequencyin_obj_t* self, uint16_t capture_period) {
static void init_pcnt(frequencyio_frequencyin_obj_t* self) {
// Prepare configuration for the PCNT unit
const pcnt_config_t pcnt_config = {
// Set PCNT input signal and control GPIOs
.pulse_gpio_num = self->pin,
.ctrl_gpio_num = PCNT_PIN_NOT_USED,
.channel = PCNT_CHANNEL_0,
// What to do on the positive / negative edge of pulse input?
.pos_mode = PCNT_COUNT_INC, // count both rising and falling edges
.neg_mode = PCNT_COUNT_INC,
// Set counter limit
.counter_h_lim = INT16_MAX,
.counter_l_lim = 0,
};
// Initialize PCNT unit
const int8_t unit = peripherals_pcnt_init(pcnt_config);
if (unit == -1) {
mp_raise_RuntimeError(translate("All PCNT units in use"));
}
// set the GPIO back to high-impedance, as pcnt_unit_config sets it as pull-up
gpio_set_pull_mode(self->pin, GPIO_FLOATING);
self->unit = (pcnt_unit_t)unit;
// enable pcnt interrupt
pcnt_event_enable(self->unit, PCNT_EVT_H_LIM);
pcnt_isr_register(pcnt_overflow_handler, (void *)self, ESP_INTR_FLAG_IRAM, &self->handle);
pcnt_intr_enable(self->unit);
}
static void init_timer(frequencyio_frequencyin_obj_t* self) {
// Prepare configuration for the timer module
timer_config_t config = {
const timer_config_t config = {
.alarm_en = true,
.counter_en = false,
.intr_type = TIMER_INTR_LEVEL,
@ -64,9 +101,9 @@ static void init_timer(frequencyio_frequencyin_obj_t* self, uint16_t capture_per
// Initialize timer module
timer_init(TIMER_GROUP_0, TIMER_0, &config);
timer_set_counter_value(TIMER_GROUP_0, TIMER_0, 0);
timer_set_alarm_value(TIMER_GROUP_0, TIMER_0, capture_period * 1000000);
timer_set_alarm_value(TIMER_GROUP_0, TIMER_0, self->capture_period * 1000000);
timer_isr_register(TIMER_GROUP_0, TIMER_0, timer_interrupt_handler, (void *)self, ESP_INTR_FLAG_IRAM, &self->handle);
timer_enable_intr(TIMER_GROUP_0, TIMER_0);
timer_isr_register(TIMER_GROUP_0, TIMER_0, frequencyin_interrupt_handler, (void *)self, ESP_INTR_FLAG_IRAM, &self->handle);
// Start timer
timer_start(TIMER_GROUP_0, TIMER_0);
@ -78,33 +115,15 @@ void common_hal_frequencyio_frequencyin_construct(frequencyio_frequencyin_obj_t*
mp_raise_ValueError(translate("Invalid capture period. Valid range: 1 - 500"));
}
// Prepare configuration for the PCNT unit
const pcnt_config_t pcnt_config = {
// Set PCNT input signal and control GPIOs
.pulse_gpio_num = pin->number,
.ctrl_gpio_num = PCNT_PIN_NOT_USED,
.channel = PCNT_CHANNEL_0,
// What to do on the positive / negative edge of pulse input?
.pos_mode = PCNT_COUNT_INC, // count both rising and falling edges
.neg_mode = PCNT_COUNT_INC,
};
// Initialize PCNT unit
const int8_t unit = peripherals_pcnt_init(pcnt_config);
if (unit == -1) {
mp_raise_RuntimeError(translate("All PCNT units in use"));
}
// set the GPIO back to high-impedance, as pcnt_unit_config sets it as pull-up
gpio_set_pull_mode(pin->number, GPIO_FLOATING);
// initialize timer
init_timer(self, capture_period);
self->pin = pin->number;
self->unit = (pcnt_unit_t)unit;
self->handle = NULL;
self->multiplier = 0;
self->capture_period = capture_period;
// initialize pcnt and timer
init_pcnt(self);
init_timer(self);
claim_pin(pin);
}
@ -118,15 +137,15 @@ void common_hal_frequencyio_frequencyin_deinit(frequencyio_frequencyin_obj_t* se
}
reset_pin_number(self->pin);
peripherals_pcnt_deinit(&self->unit);
if (self->handle) {
timer_deinit(TIMER_GROUP_0, TIMER_0);
if (self->handle) {
esp_intr_free(self->handle);
self->handle = NULL;
}
}
uint32_t common_hal_frequencyio_frequencyin_get_item(frequencyio_frequencyin_obj_t* self) {
return self->frequency;
return (self->frequency + (self->multiplier * INT16_MAX));
}
void common_hal_frequencyio_frequencyin_pause(frequencyio_frequencyin_obj_t* self) {

3
ports/esp32s2/common-hal/frequencyio/FrequencyIn.h
View File

@ -36,7 +36,8 @@ typedef struct {
pcnt_unit_t unit;
intr_handle_t handle;
uint8_t pin;
uint32_t frequency;
uint8_t multiplier;
uint16_t frequency;
uint16_t capture_period;
} frequencyio_frequencyin_obj_t;