frequencyio implementation for esp32s2

ports/esp32s2/common-hal/frequencyio/FrequencyIn.c

@@ -0,0 +1,158 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 microDev
+ *
+ * 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 "shared-bindings/frequencyio/FrequencyIn.h"
+
+#include <stdint.h>
+
+#include "py/runtime.h"
+
+#include "supervisor/shared/tick.h"
+#include "shared-bindings/time/__init__.h"
+
+#include "common-hal/microcontroller/Pin.h"
+
+static void frequencyin_interrupt_handler(void *self_in) {
+    frequencyio_frequencyin_obj_t* self = self_in;
+    // get counter value
+    int16_t count;
+    pcnt_get_counter_value(self->unit, &count);
+    self->frequency = count / 2.0 / self->capture_period;
+
+    // reset counter
+    pcnt_counter_clear(self->unit);
+}
+
+static void init_timer(frequencyio_frequencyin_obj_t* self, uint16_t capture_period) {
+    // Prepare configuration for the timer module
+    timer_config_t config = {
+        .alarm_en = true,
+        .counter_en = false,
+        .intr_type = TIMER_INTR_LEVEL,
+        .counter_dir = TIMER_COUNT_UP,
+        .auto_reload = true,
+        .divider = 80            // 1 us per tick
+    };
+
+    // 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_enable_intr(TIMER_GROUP_0, TIMER_0);
+    timer_isr_register(TIMER_GROUP_0, TIMER_0, &frequencyin_interrupt_handler, (void *)self, 0, &self->handle);
+
+    // Start timer
+    timer_start(TIMER_GROUP_0, TIMER_0);
+}
+
+void common_hal_frequencyio_frequencyin_construct(frequencyio_frequencyin_obj_t* self,
+        const mcu_pin_obj_t* pin, const uint16_t capture_period) {
+    if ((capture_period == 0) || (capture_period > 500)) {
+        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,
+        .lctrl_mode = PCNT_MODE_DISABLE,
+        .hctrl_mode = PCNT_MODE_KEEP,
+        .pos_mode = PCNT_COUNT_INC,  // count both rising and falling edges
+        .neg_mode = PCNT_COUNT_INC,
+        .counter_h_lim = 0,
+        .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(pin->number, GPIO_FLOATING);
+
+    // initialize timer
+    init_timer(self, capture_period);
+
+    self->pin = pin->number;
+    self->unit = (pcnt_unit_t)unit;
+    self->capture_period = capture_period;
+
+    claim_pin(pin);
+}
+
+bool common_hal_frequencyio_frequencyin_deinited(frequencyio_frequencyin_obj_t* self) {
+    return self->unit == PCNT_UNIT_MAX;
+}
+
+void common_hal_frequencyio_frequencyin_deinit(frequencyio_frequencyin_obj_t* self) {
+    if (common_hal_frequencyio_frequencyin_deinited(self)) {
+        return;
+    }
+    reset_pin_number(self->pin);
+    peripherals_pcnt_deinit(&self->unit);
+    if (self->handle) {
+        timer_deinit(TIMER_GROUP_0, TIMER_0);
+        esp_intr_free(self->handle);
+        self->handle = NULL;
+    }
+}
+
+uint32_t common_hal_frequencyio_frequencyin_get_item(frequencyio_frequencyin_obj_t* self) {
+    return (1000 / (self->capture_period / self->frequency));
+}
+
+void common_hal_frequencyio_frequencyin_pause(frequencyio_frequencyin_obj_t* self) {
+    pcnt_counter_pause(self->unit);
+    timer_pause(TIMER_GROUP_0, TIMER_0);
+}
+
+void common_hal_frequencyio_frequencyin_resume(frequencyio_frequencyin_obj_t* self) {
+    pcnt_counter_resume(self->unit);
+    timer_start(TIMER_GROUP_0, TIMER_0);
+}
+
+void common_hal_frequencyio_frequencyin_clear(frequencyio_frequencyin_obj_t* self) {
+    self->frequency = 0;
+    pcnt_counter_clear(self->unit);
+    timer_set_counter_value(TIMER_GROUP_0, TIMER_0, 0);
+}
+
+uint16_t common_hal_frequencyio_frequencyin_get_capture_period(frequencyio_frequencyin_obj_t *self) {
+    return self->capture_period;
+}
+
+void common_hal_frequencyio_frequencyin_set_capture_period(frequencyio_frequencyin_obj_t *self, uint16_t capture_period) {
+    if ((capture_period == 0) || (capture_period > 500)) {
+        mp_raise_ValueError(translate("Invalid capture period. Valid range: 1 - 500"));
+    }
+    self->capture_period = capture_period;
+    common_hal_frequencyio_frequencyin_clear(self);
+    timer_set_alarm_value(TIMER_GROUP_0, TIMER_0, capture_period * 1000000);
+}

ports/esp32s2/common-hal/frequencyio/FrequencyIn.h

@@ -0,0 +1,43 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 microDev
+ *
+ * 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.
+ */
+
+#ifndef MICROPY_INCLUDED_ESP32S2_COMMON_HAL_FREQUENCYIO_FREQUENCYIN_H
+#define MICROPY_INCLUDED_ESP32S2_COMMON_HAL_FREQUENCYIO_FREQUENCYIN_H
+
+#include "py/obj.h"
+#include "driver/timer.h"
+#include "peripherals/pcnt.h"
+
+typedef struct {
+    mp_obj_base_t base;
+    pcnt_unit_t unit;
+    intr_handle_t handle;
+    uint8_t pin;
+    uint32_t frequency;
+    uint16_t capture_period;
+} frequencyio_frequencyin_obj_t;
+
+#endif // MICROPY_INCLUDED_ESP32S2_COMMON_HAL_FREQUENCYIO_FREQUENCYIN_H

ports/esp32s2/common-hal/frequencyio/__init__.c

@@ -0,0 +1 @@
+// No ferquencyio module functions.

ports/esp32s2/mpconfigport.mk

@@ -18,7 +18,7 @@ CIRCUITPY_AUDIOBUSIO = 0
 CIRCUITPY_AUDIOIO = 0
 CIRCUITPY_CANIO = 1
 CIRCUITPY_COUNTIO = 1
-CIRCUITPY_FREQUENCYIO = 0
+CIRCUITPY_FREQUENCYIO = 1
 CIRCUITPY_I2CPERIPHERAL = 0
 CIRCUITPY_ROTARYIO = 1
 CIRCUITPY_NVM = 0