Phase 7: EC11 encoder, life counter views, WS2812B RMT + LEDC buzzer feedback, E2E UI state machine; document build/hardware notes

main/buzzer.c

@@ -0,0 +1,84 @@
+/*
+ * MTG RFID Companion - Piezo buzzer driver (LEDC PWM)
+ */
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_log.h"
+#include "driver/ledc.h"
+#include "hw_pins.h"
+#include "buzzer.h"
+
+static const char *TAG = "buzzer";
+
+#define BUZZER_SPEED_MODE LEDC_LOW_SPEED_MODE
+#define BUZZER_TIMER_NUM  LEDC_TIMER_0
+#define BUZZER_CHANNEL    LEDC_CHANNEL_0
+
+esp_err_t buzzer_init(void)
+{
+    ledc_timer_config_t timer_cfg = {
+        .speed_mode = BUZZER_SPEED_MODE,
+        .timer_num = BUZZER_TIMER_NUM,
+        .duty_resolution = LEDC_TIMER_13_BIT,
+        .freq_hz = 2000,
+        .clk_cfg = LEDC_AUTO_CLK,
+    };
+    esp_err_t ret = ledc_timer_config(&timer_cfg);
+    if (ret != ESP_OK) {
+        return ret;
+    }
+
+    ledc_channel_config_t chan_cfg = {
+        .gpio_num = HW_BUZZER_GPIO,
+        .speed_mode = BUZZER_SPEED_MODE,
+        .channel = BUZZER_CHANNEL,
+        .timer_sel = BUZZER_TIMER_NUM,
+        .duty = 0,
+        .hpoint = 0,
+    };
+    ret = ledc_channel_config(&chan_cfg);
+    if (ret != ESP_OK) {
+        return ret;
+    }
+
+    ESP_LOGI(TAG, "buzzer ready on GPIO %d", HW_BUZZER_GPIO);
+    return ESP_OK;
+}
+
+esp_err_t buzzer_start(uint32_t freq_hz, uint32_t duty_percent)
+{
+    if (freq_hz == 0) {
+        return buzzer_stop();
+    }
+    uint32_t duty = ((uint32_t)1 << 13) * duty_percent / 100u;
+    if (duty_percent >= 100) {
+        duty = ((uint32_t)1 << 13);
+    }
+
+    esp_err_t ret = ledc_set_freq(BUZZER_SPEED_MODE, BUZZER_TIMER_NUM, freq_hz);
+    if (ret != ESP_OK) {
+        return ret;
+    }
+    ret = ledc_set_duty(BUZZER_SPEED_MODE, BUZZER_CHANNEL, duty);
+    if (ret != ESP_OK) {
+        return ret;
+    }
+    return ledc_update_duty(BUZZER_SPEED_MODE, BUZZER_CHANNEL);
+}
+
+esp_err_t buzzer_stop(void)
+{
+    ledc_set_duty(BUZZER_SPEED_MODE, BUZZER_CHANNEL, 0);
+    return ledc_update_duty(BUZZER_SPEED_MODE, BUZZER_CHANNEL);
+}
+
+esp_err_t buzzer_chirp(uint32_t freq_hz, uint32_t duration_ms)
+{
+    esp_err_t ret = buzzer_start(freq_hz, 30);
+    if (ret != ESP_OK) {
+        return ret;
+    }
+    vTaskDelay(pdMS_TO_TICKS(duration_ms));
+    return buzzer_stop();
+}