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

main/led_manager.c

@@ -0,0 +1,90 @@
+/*
+ * MTG RFID Companion - WS2812B Neopixel LED manager (RMT)
+ */
+
+#include "esp_log.h"
+#include "driver/rmt_tx.h"
+#include "driver/rmt_encoder.h"
+#include "hw_pins.h"
+#include "led_manager.h"
+
+static const char *TAG = "led";
+
+static rmt_channel_handle_t s_tx_chan = NULL;
+static rmt_encoder_handle_t s_enc = NULL;
+
+esp_err_t led_manager_init(void)
+{
+    if (s_tx_chan != NULL) {
+        return ESP_OK;
+    }
+
+    rmt_tx_channel_config_t chan_cfg = {
+        .gpio_num = HW_NEOPIXEL_GPIO,
+        .clk_src = RMT_CLK_SRC_DEFAULT,
+        .resolution_hz = 10 * 1000 * 1000, /* 100 ns per tick */
+        .mem_block_symbols = 64,
+        .trans_queue_depth = 4,
+    };
+    esp_err_t ret = rmt_new_tx_channel(&chan_cfg, &s_tx_chan);
+    if (ret != ESP_OK) {
+        ESP_LOGE(TAG, "rmt_new_tx_channel failed: %s", esp_err_to_name(ret));
+        return ret;
+    }
+
+    rmt_bytes_encoder_config_t enc_cfg = {
+        .bit0 = {
+            .duration0 = 4, /* T0H ~ 400 ns */
+            .level0 = 1,
+            .duration1 = 8, /* T0L ~ 800 ns */
+            .level1 = 0,
+        },
+        .bit1 = {
+            .duration0 = 9, /* T1H ~ 900 ns */
+            .level0 = 1,
+            .duration1 = 4, /* T1L ~ 400 ns */
+            .level1 = 0,
+        },
+    };
+    ret = rmt_new_bytes_encoder(&enc_cfg, &s_enc);
+    if (ret != ESP_OK) {
+        ESP_LOGE(TAG, "rmt_new_bytes_encoder failed: %s", esp_err_to_name(ret));
+        return ret;
+    }
+
+    ret = rmt_enable(s_tx_chan);
+    if (ret != ESP_OK) {
+        ESP_LOGE(TAG, "rmt_enable failed: %s", esp_err_to_name(ret));
+        return ret;
+    }
+
+    ESP_LOGI(TAG, "WS2812B LED ready on GPIO %d", HW_NEOPIXEL_GPIO);
+    return ESP_OK;
+}
+
+esp_err_t led_manager_set_color(uint8_t r, uint8_t g, uint8_t b)
+{
+    if (s_tx_chan == NULL) {
+        esp_err_t ret = led_manager_init();
+        if (ret != ESP_OK) {
+            return ret;
+        }
+    }
+
+    /* WS2812B expects GRB byte order */
+    uint8_t txbuf[3] = { g, r, b };
+
+    rmt_transmit_config_t tx_cfg = {
+        .loop_count = 0, /* one-shot; LED latches and holds the level */
+    };
+    esp_err_t ret = rmt_transmit(s_tx_chan, s_enc, txbuf, sizeof(txbuf), &tx_cfg);
+    if (ret != ESP_OK) {
+        return ret;
+    }
+    return rmt_tx_wait_all_done(s_tx_chan, pdMS_TO_TICKS(50));
+}
+
+esp_err_t led_manager_off(void)
+{
+    return led_manager_set_color(0, 0, 0);
+}