first commit

.gitignore

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+.cache
+build

CMakeLists.txt

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+# The following five lines of boilerplate have to be in your project's
+# CMakeLists in this exact order for cmake to work correctly
+cmake_minimum_required(VERSION 3.16)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(esp-pwm)

main/CMakeLists.txt

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+idf_component_register(SRCS "esp-pwm.c"
+                    INCLUDE_DIRS ".")

main/esp-pwm.c

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+#include <stdio.h>
+#include <math.h>
+
+#include "driver/ledc.h"
+#include "hal/ledc_types.h"
+#include "soc/clk_tree_defs.h"
+#include "esp_clk_tree.h"
+#include "esp_log.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+const char* TAG = "MAIN_CPP";
+
+void app_main() {
+    ESP_LOGI(TAG, "BOOT\n");
+
+    const uint32_t timer_freq = 2731;
+
+    uint32_t clk_freq = 0;
+    ESP_ERROR_CHECK(esp_clk_tree_src_get_freq_hz(SOC_MOD_CLK_RC_FAST, ESP_CLK_TREE_SRC_FREQ_PRECISION_EXACT, &clk_freq));
+
+    uint32_t duty_resolution = ledc_find_suitable_duty_resolution(clk_freq, timer_freq);
+    if (duty_resolution == 0) {
+        ESP_LOGE(TAG, "Could not determine optimal duty resolution.\n");
+        return;
+    }
+
+    ledc_timer_config_t ledc_config = {
+        .speed_mode = LEDC_LOW_SPEED_MODE,
+        .timer_num = LEDC_TIMER_0,
+        .freq_hz = timer_freq,
+        .duty_resolution = duty_resolution,
+        .clk_cfg = LEDC_USE_RC_FAST_CLK
+    };
+
+    ESP_ERROR_CHECK(ledc_timer_config(&ledc_config));
+
+    ledc_channel_config_t ledc_ch_config = {
+        .gpio_num = 9,
+        .speed_mode = LEDC_LOW_SPEED_MODE,
+        .channel = LEDC_CHANNEL_0,
+        .timer_sel = LEDC_TIMER_0,
+        .duty = (uint32_t) (pow(2, duty_resolution) / 2),
+        // .hpoint = ((uint32_t) pow(2, duty_resolution)) - 1,
+        .hpoint = 0,
+        .sleep_mode = LEDC_SLEEP_MODE_KEEP_ALIVE,
+        .flags.output_invert = false
+    };
+
+    ESP_ERROR_CHECK(ledc_channel_config(&ledc_ch_config));
+
+    while (true) {
+        vTaskDelay(10000);   
+    }
+}