Dim LED ring, add blink mode, and signal OTA outcome on the ring.

Default brightness is ~5%; UART blink mode and green/red pulses mark OTA success or failure. Failed UART uploads skip ESP-NOW distribution.

Co-authored-by: Cursor <cursoragent@cursor.com>

goTool/README.md

@@ -29,7 +29,7 @@ go run . -port /dev/ttyUSB0 clients
 | `serve` | — | Web dashboard at `http://localhost:8080` (WebSocket live updates) |
 | `ota` | 16–19 | UART firmware upload to master; firmware then pushes to slaves via ESP-NOW |
 | `ota-progress` | 21 | Query per-slave ESP-NOW OTA progress on the master (`-client N`, default all) |
-| `led-ring` | 8 | LED ring: `-mode clear\|progress\|digit`, `-progress`, `-digit`, RGB, `-intensity` |
+| `led-ring` | 8 | LED ring: `-mode clear\|progress\|digit\|blink`, `-progress`, `-digit`, RGB, `-intensity` (0 = ~5 %), `-blink-ms`, `-blink-count` |
 
 `clients` requires slaves to have responded to master discover broadcasts first.
 

goTool/cmd_led_ring.go

@@ -11,17 +11,20 @@ const (
 	ledRingModeClear    = 0
 	ledRingModeProgress = 1
 	ledRingModeDigit    = 2
+	ledRingModeBlink    = 3
 )
 
 func runLedRing(sp *serialPort, args []string) error {
 	fs := flag.NewFlagSet("led-ring", flag.ExitOnError)
-	mode := fs.String("mode", "progress", "clear, progress, or digit")
+	mode := fs.String("mode", "progress", "clear, progress, digit, or blink")
 	progress := fs.Uint("progress", 0, "fill level 0–100 (mode=progress)")
 	digit := fs.Uint("digit", 0, "digit 0–10 (mode=digit)")
 	r := fs.Uint("r", 0, "red 0–255")
 	g := fs.Uint("g", 255, "green 0–255")
 	b := fs.Uint("b", 0, "blue 0–255")
-	intensity := fs.Uint("intensity", 255, "brightness 0–255")
+	intensity := fs.Uint("intensity", 0, "brightness 0–255 (0 = device default ~5%)")
+	blinkMs := fs.Uint("blink-ms", 350, "pulse length in ms (mode=blink)")
+	blinkCount := fs.Uint("blink-count", 1, "number of pulses (mode=blink)")
 	if err := fs.Parse(args); err != nil {
 		return err
 	}
@@ -34,18 +37,22 @@ func runLedRing(sp *serialPort, args []string) error {
 		modeVal = ledRingModeProgress
 	case "digit":
 		modeVal = ledRingModeDigit
+	case "blink":
+		modeVal = ledRingModeBlink
 	default:
-		return fmt.Errorf("unknown -mode %q (clear, progress, digit)", *mode)
+		return fmt.Errorf("unknown -mode %q (clear, progress, digit, blink)", *mode)
 	}
 
 	resp, err := sp.ledRingProgress(&pb.LedRingProgressRequest{
-		Mode:      modeVal,
+		Mode:       modeVal,
-		Progress:  uint32(*progress),
+		Progress:   uint32(*progress),
-		Digit:     uint32(*digit),
+		Digit:      uint32(*digit),
-		R:         uint32(*r),
+		R:          uint32(*r),
-		G:         uint32(*g),
+		G:          uint32(*g),
-		B:         uint32(*b),
+		B:          uint32(*b),
-		Intensity: uint32(*intensity),
+		Intensity:  uint32(*intensity),
+		BlinkMs:    uint32(*blinkMs),
+		BlinkCount: uint32(*blinkCount),
 	})
 	if err != nil {
 		return err

goTool/pb/uart_messages.pb.go

@@ -1068,8 +1068,8 @@ func (x *EspNowUnicastTestResponse) GetSeq() uint32 {
 	return 0
 }
 
-// Host → device: LED ring display (progress bar, digit, or clear).
+// Host → device: LED ring display (progress bar, digit, clear, or blink).
-// mode: 0=clear, 1=progress (0–100 %), 2=digit (0–10, same layout as firmware digit maps).
+// mode: 0=clear, 1=progress (0–100 %), 2=digit (0–10), 3=blink full ring.
 type LedRingProgressRequest struct {
 	state protoimpl.MessageState `protogen:"open.v1"`
 	Mode  uint32                 `protobuf:"varint,1,opt,name=mode,proto3" json:"mode,omitempty"`
@@ -1080,8 +1080,12 @@ type LedRingProgressRequest struct {
 	R     uint32 `protobuf:"varint,4,opt,name=r,proto3" json:"r,omitempty"`
 	G     uint32 `protobuf:"varint,5,opt,name=g,proto3" json:"g,omitempty"`
 	B     uint32 `protobuf:"varint,6,opt,name=b,proto3" json:"b,omitempty"`
-	// * 0–255 brightness scale applied to r/g/b
+	// * 0–255 brightness scale; 0 = firmware default (~5 %)
-	Intensity     uint32 `protobuf:"varint,7,opt,name=intensity,proto3" json:"intensity,omitempty"`
+	Intensity uint32 `protobuf:"varint,7,opt,name=intensity,proto3" json:"intensity,omitempty"`
+	// * Pulse length in ms (mode=blink, default 350)
+	BlinkMs uint32 `protobuf:"varint,8,opt,name=blink_ms,json=blinkMs,proto3" json:"blink_ms,omitempty"`
+	// * Number of pulses (mode=blink, default 1)
+	BlinkCount    uint32 `protobuf:"varint,9,opt,name=blink_count,json=blinkCount,proto3" json:"blink_count,omitempty"`
 	unknownFields protoimpl.UnknownFields
 	sizeCache     protoimpl.SizeCache
 }
@@ -1165,6 +1169,20 @@ func (x *LedRingProgressRequest) GetIntensity() uint32 {
 	return 0
 }
 
+func (x *LedRingProgressRequest) GetBlinkMs() uint32 {
+	if x != nil {
+		return x.BlinkMs
+	}
+	return 0
+}
+
+func (x *LedRingProgressRequest) GetBlinkCount() uint32 {
+	if x != nil {
+		return x.BlinkCount
+	}
+	return 0
+}
+
 type LedRingProgressResponse struct {
 	state         protoimpl.MessageState `protogen:"open.v1"`
 	Success       bool                   `protobuf:"varint,1,opt,name=success,proto3" json:"success,omitempty"`
@@ -1707,7 +1725,7 @@ const file_uart_messages_proto_rawDesc = "" +
 	"\x03seq\x18\x02 \x01(\rR\x03seq\"G\n" +
 	"\x19EspNowUnicastTestResponse\x12\x18\n" +
 	"\asuccess\x18\x01 \x01(\bR\asuccess\x12\x10\n" +
-	"\x03seq\x18\x02 \x01(\rR\x03seq\"\xa6\x01\n" +
+	"\x03seq\x18\x02 \x01(\rR\x03seq\"\xe2\x01\n" +
 	"\x16LedRingProgressRequest\x12\x12\n" +
 	"\x04mode\x18\x01 \x01(\rR\x04mode\x12\x1a\n" +
 	"\bprogress\x18\x02 \x01(\rR\bprogress\x12\x14\n" +
@@ -1715,7 +1733,10 @@ const file_uart_messages_proto_rawDesc = "" +
 	"\x01r\x18\x04 \x01(\rR\x01r\x12\f\n" +
 	"\x01g\x18\x05 \x01(\rR\x01g\x12\f\n" +
 	"\x01b\x18\x06 \x01(\rR\x01b\x12\x1c\n" +
-	"\tintensity\x18\a \x01(\rR\tintensity\"y\n" +
+	"\tintensity\x18\a \x01(\rR\tintensity\x12\x19\n" +
+	"\bblink_ms\x18\b \x01(\rR\ablinkMs\x12\x1f\n" +
+	"\vblink_count\x18\t \x01(\rR\n" +
+	"blinkCount\"y\n" +
 	"\x17LedRingProgressResponse\x12\x18\n" +
 	"\asuccess\x18\x01 \x01(\bR\asuccess\x12\x12\n" +
 	"\x04mode\x18\x02 \x01(\rR\x04mode\x12\x1a\n" +

main/README.md

@@ -253,6 +253,8 @@ Inactive app partition is selected with `esp_ota_get_next_update_partition()`; `
 
 `OTA_END` can take a long time on the wire (slave flash + ESP-NOW); the host should use a generous read timeout.
 
+During OTA the LED ring shows progress at ~5 % brightness: **blue** while the image is written (UART on master, ESP-NOW on slaves), **green** on the master while it forwards the image to slaves over ESP-NOW. On **success** the ring gives one short **green** blink; on **failure** one **red** blink and ESP-NOW distribution is not started (failed UART upload / `OTA_END` validation).
+
 `OTA_START_ESPNOW` (type `20`): re-run ESP-NOW distribution from the last staged image without a new UART upload (no-op if nothing staged).
 
 Implementation: `ota_uart.c` (4 KiB buffer, `esp_ota_write`), `ota_espnow.c`, `cmd_ota.c`.
@@ -319,11 +321,12 @@ Control the 95-LED ring from the host. The firmware **does not** animate digits
 
 | Field | Meaning |
 |-------|---------|
-| `mode` | `0` = clear, `1` = progress bar, `2` = digit |
+| `mode` | `0` = clear, `1` = progress bar, `2` = digit, `3` = blink full ring |
 | `progress` | 0–100 (% of ring lit, mode `1`) |
 | `digit` | 0–10 (mode `2`, same segment maps as built-in digits) |
 | `r`, `g`, `b` | Color 0–255 |
-| `intensity` | Brightness 0–255 (scaled into RGB; `0` → 255) |
+| `intensity` | Brightness 0–255 (scaled into RGB; `0` → firmware default ~5 %) |
+| `blink_ms`, `blink_count` | Pulse length and count (mode `3`; defaults 350 ms, 1) |
 
 **Response:** `led_ring_progress_response` (`success`, `mode`, `progress`, `digit`).
 
@@ -331,6 +334,7 @@ Control the 95-LED ring from the host. The firmware **does not** animate digits
 go run . -port /dev/ttyUSB0 led-ring -mode progress -progress 75 -g 80 -b 255
 go run . -port /dev/ttyUSB0 led-ring -mode digit -digit 7 -r 255 -g 200
 go run . -port /dev/ttyUSB0 led-ring -mode clear
+go run . -port /dev/ttyUSB0 led-ring -mode blink -g 255 -blink-count 2
 ```
 
 ### CLIENT_INFO command

main/cmd_led_ring.c

@@ -8,6 +8,7 @@ static const char *TAG = "[LED_RING_CMD]";
 #define LED_RING_MODE_CLEAR    0
 #define LED_RING_MODE_PROGRESS 1
 #define LED_RING_MODE_DIGIT    2
+#define LED_RING_MODE_BLINK    3
 
 static uint8_t clamp_u8(uint32_t v) {
   if (v > 255) {
@@ -23,13 +24,11 @@ static uint8_t clamp_progress(uint32_t v) {
   return (uint8_t)v;
 }
 
-static void apply_intensity(uint8_t *r, uint8_t *g, uint8_t *b, uint8_t intensity) {
+static uint8_t resolve_intensity(uint32_t intensity) {
   if (intensity == 0) {
-    return;
+    return LED_RING_DEFAULT_INTENSITY;
   }
-  *r = (uint16_t)(*r) * intensity / 255;
+  return clamp_u8(intensity);
-  *g = (uint16_t)(*g) * intensity / 255;
-  *b = (uint16_t)(*b) * intensity / 255;
 }
 
 static void reply(bool success, uint32_t mode, uint32_t progress, uint32_t digit) {
@@ -64,11 +63,7 @@ static void handle_led_ring(const uint8_t *data, size_t len) {
   uint8_t r = clamp_u8(req.r);
   uint8_t g = clamp_u8(req.g);
   uint8_t b = clamp_u8(req.b);
-  uint8_t intensity = clamp_u8(req.intensity);
+  uint8_t intensity = resolve_intensity(req.intensity);
-  if (intensity == 0) {
-    intensity = 255;
-  }
-  apply_intensity(&r, &g, &b, intensity);
 
   led_command_t cmd = {0};
 
@@ -106,6 +101,7 @@ static void handle_led_ring(const uint8_t *data, size_t len) {
     cmd.r = r;
     cmd.g = g;
     cmd.b = b;
+    cmd.intensity = intensity;
     led_ring_send_command(&cmd);
     ESP_LOGI(TAG, "digit %u rgb=%u,%u,%u", (unsigned)cmd.value, (unsigned)r,
              (unsigned)g, (unsigned)b);
@@ -113,6 +109,24 @@ static void handle_led_ring(const uint8_t *data, size_t len) {
     return;
   }
 
+  case LED_RING_MODE_BLINK: {
+    cmd.mode = LED_CMD_BLINK;
+    cmd.r = r;
+    cmd.g = g;
+    cmd.b = b;
+    cmd.intensity = intensity;
+    cmd.blink_ms = (uint16_t)(req.blink_ms > 0 ? req.blink_ms : 350);
+    cmd.blink_count = req.blink_count > 0 ? (uint8_t)req.blink_count : 1;
+    if (cmd.blink_count == 0) {
+      cmd.blink_count = 1;
+    }
+    led_ring_send_command(&cmd);
+    ESP_LOGI(TAG, "blink x%u %u ms rgb=%u,%u,%u", (unsigned)cmd.blink_count,
+             (unsigned)cmd.blink_ms, (unsigned)r, (unsigned)g, (unsigned)b);
+    reply(true, mode, 0, 0);
+    return;
+  }
+
   default:
     ESP_LOGW(TAG, "unknown mode %lu", (unsigned long)mode);
     reply(false, mode, 0, 0);

main/cmd_ota.c

@@ -1,4 +1,5 @@
 #include "cmd_ota.h"
+#include "led_ring.h"
 #include "ota_espnow.h"
 #include "ota_uart.h"
 #include "uart_cmd.h"
@@ -15,6 +16,15 @@ static const char *TAG = "[OTA_CMD]";
 #define OTA_DIST_STACK 8192
 #define OTA_DIST_PRIO 5
 
+/** UART OTA upload to this node (master). */
+#define OTA_LED_UART_R 0
+#define OTA_LED_UART_G 0
+#define OTA_LED_UART_B 255
+/** ESP-NOW distribution from master to slaves. */
+#define OTA_LED_ESPNOW_TX_R 0
+#define OTA_LED_ESPNOW_TX_G 255
+#define OTA_LED_ESPNOW_TX_B 0
+
 typedef struct {
   uint32_t written;
   int slot;
@@ -32,6 +42,11 @@ static void send_ota_status(ota_uart_status_t status, uint32_t err_code) {
   uart_cmd_send(&response, TAG);
 }
 
+static void send_ota_failed(uint32_t err_code) {
+  led_ring_ota_failed();
+  send_ota_status(OTA_UART_ST_FAILED, err_code);
+}
+
 static void send_ota_distributing(uint32_t kind, uint32_t bytes_done,
                                  uint32_t target_slot) {
   alox_UartMessage response;
@@ -46,7 +61,9 @@ static void send_ota_distributing(uint32_t kind, uint32_t bytes_done,
 
 static void ota_dist_aggregate(uint32_t bytes_done, uint32_t total_bytes,
                                uint8_t slave_count) {
-  (void)total_bytes;
+  (void)slave_count;
+  led_ring_show_ota_progress(bytes_done, total_bytes, OTA_LED_ESPNOW_TX_R,
+                             OTA_LED_ESPNOW_TX_G, OTA_LED_ESPNOW_TX_B);
   send_ota_distributing(OTA_DIST_AGGREGATE, bytes_done, (uint32_t)slave_count);
 }
 
@@ -68,7 +85,7 @@ static void ota_prepare_task(void *param) {
 
   int slot = ota_uart_prepare(total_size);
   if (slot < 0) {
-    send_ota_status(OTA_UART_ST_FAILED, 1);
+    send_ota_failed(1);
     vTaskDelete(NULL);
     return;
   }
@@ -82,6 +99,9 @@ static void ota_prepare_task(void *param) {
   response.payload.ota_status.error = 0;
   uart_cmd_send(&response, TAG);
 
+  led_ring_show_ota_progress(0, total_size, OTA_LED_UART_R, OTA_LED_UART_G,
+                             OTA_LED_UART_B);
+
   vTaskDelete(NULL);
 }
 
@@ -90,7 +110,7 @@ static void handle_ota_start(const uint8_t *data, size_t len) {
   alox_OtaStartPayload req = alox_OtaStartPayload_init_zero;
 
   if (uart_cmd_decode(data, len, &uart_msg) != ESP_OK) {
-    send_ota_status(OTA_UART_ST_FAILED, 2);
+    send_ota_failed( 2);
     return;
   }
 
@@ -102,13 +122,13 @@ static void handle_ota_start(const uint8_t *data, size_t len) {
 
   if (req.total_size == 0) {
     ESP_LOGW(TAG, "OTA_START: total_size required");
-    send_ota_status(OTA_UART_ST_FAILED, 3);
+    send_ota_failed( 3);
     return;
   }
 
   if (ota_uart_is_active()) {
     ESP_LOGW(TAG, "OTA_START while session active");
-    send_ota_status(OTA_UART_ST_FAILED, 4);
+    send_ota_failed( 4);
     return;
   }
 
@@ -116,7 +136,7 @@ static void handle_ota_start(const uint8_t *data, size_t len) {
                   (void *)(uintptr_t)req.total_size, OTA_PREPARE_PRIO,
                   NULL) != pdPASS) {
     ESP_LOGE(TAG, "failed to create ota_prepare task");
-    send_ota_status(OTA_UART_ST_FAILED, 5);
+    send_ota_failed( 5);
   }
 }
 
@@ -125,7 +145,7 @@ static void handle_ota_payload(const uint8_t *data, size_t len) {
 
   if (uart_cmd_decode(data, len, &uart_msg) != ESP_OK) {
     ESP_LOGW(TAG, "OTA_PAYLOAD decode failed");
-    send_ota_status(OTA_UART_ST_FAILED, 10);
+    send_ota_failed( 10);
     return;
   }
 
@@ -134,34 +154,47 @@ static void handle_ota_payload(const uint8_t *data, size_t len) {
   if (req_ptr == NULL) {
     ESP_LOGW(TAG, "OTA_PAYLOAD: missing ota_payload (which=%u)",
              (unsigned)uart_msg.which_payload);
-    send_ota_status(OTA_UART_ST_FAILED, 11);
+    send_ota_failed( 11);
     return;
   }
 
   if (req_ptr->data.size == 0) {
     ESP_LOGW(TAG, "OTA_PAYLOAD: empty data (seq=%lu)",
              (unsigned long)req_ptr->seq);
-    send_ota_status(OTA_UART_ST_FAILED, 11);
+    send_ota_failed( 11);
     return;
   }
 
   if (!ota_uart_is_active()) {
     ESP_LOGW(TAG, "OTA_PAYLOAD without active session (seq=%lu)",
              (unsigned long)req_ptr->seq);
-    send_ota_status(OTA_UART_ST_FAILED, 12);
+    send_ota_failed( 12);
     return;
   }
 
   ota_feed_result_t r =
       ota_uart_feed(req_ptr->data.bytes, req_ptr->data.size);
   if (r == OTA_FEED_ERROR) {
-    send_ota_status(OTA_UART_ST_FAILED, 13);
+    send_ota_failed( 13);
     return;
   }
   if (r == OTA_FEED_BLOCK_WRITTEN) {
+    uint32_t total = ota_uart_total_size();
+    uint32_t done = ota_uart_bytes_written();
     ESP_LOGI(TAG, "OTA block ack (%lu bytes in flash)",
-             (unsigned long)ota_uart_bytes_written());
+             (unsigned long)done);
+    led_ring_show_ota_progress(done, total, OTA_LED_UART_R, OTA_LED_UART_G,
+                               OTA_LED_UART_B);
     send_ota_status(OTA_UART_ST_BLOCK_ACK, 0);
+    return;
+  }
+
+  if (r == OTA_FEED_OK) {
+    uint32_t total = ota_uart_total_size();
+    if (total > 0) {
+      led_ring_show_ota_progress(ota_uart_bytes_received(), total,
+                                 OTA_LED_UART_R, OTA_LED_UART_G, OTA_LED_UART_B);
+    }
   }
 }
 
@@ -175,19 +208,21 @@ static void ota_distribute_task(void *param) {
   const esp_partition_t *part = NULL;
   uint32_t image_size = 0;
   if (!ota_uart_get_staged_image(&part, &image_size)) {
-    send_ota_status(OTA_UART_ST_FAILED, 30);
+    send_ota_failed( 30);
     free(job);
     vTaskDelete(NULL);
     return;
   }
 
+  led_ring_show_ota_progress(0, image_size, OTA_LED_ESPNOW_TX_R, OTA_LED_ESPNOW_TX_G,
+                             OTA_LED_ESPNOW_TX_B);
   send_ota_distributing(OTA_DIST_AGGREGATE, 0, 0);
 
   esp_err_t err = ota_espnow_distribute(part, image_size, &s_dist_progress);
   if (err != ESP_OK) {
     ESP_LOGE(TAG, "slave OTA distribution failed: %s", esp_err_to_name(err));
     ota_uart_clear_staged();
-    send_ota_status(OTA_UART_ST_FAILED, 31);
+    send_ota_failed(31);
     free(job);
     vTaskDelete(NULL);
     return;
@@ -195,12 +230,15 @@ static void ota_distribute_task(void *param) {
 
   err = ota_uart_apply_boot();
   if (err != ESP_OK) {
-    send_ota_status(OTA_UART_ST_FAILED, (uint32_t)err);
+    send_ota_failed((uint32_t)err);
     free(job);
     vTaskDelete(NULL);
     return;
   }
 
+  led_ring_show_ota_progress(image_size, image_size, OTA_LED_ESPNOW_TX_R,
+                             OTA_LED_ESPNOW_TX_G, OTA_LED_ESPNOW_TX_B);
+
   alox_UartMessage response;
   uart_cmd_init_response(&response, alox_MessageType_OTA_STATUS,
                          alox_UartMessage_ota_status_tag);
@@ -211,6 +249,7 @@ static void ota_distribute_task(void *param) {
   response.payload.ota_status.error = 0;
   uart_cmd_send(&response, TAG);
 
+  led_ring_ota_success();
   free(job);
   vTaskDelete(NULL);
 }
@@ -220,30 +259,36 @@ static void handle_ota_end(const uint8_t *data, size_t len) {
   (void)len;
 
   if (!ota_uart_is_active()) {
-    send_ota_status(OTA_UART_ST_FAILED, 20);
+    send_ota_failed( 20);
     return;
   }
 
   ota_dist_job_t *job = calloc(1, sizeof(*job));
   if (job == NULL) {
-    send_ota_status(OTA_UART_ST_FAILED, 21);
+    send_ota_failed( 21);
     return;
   }
   job->written = ota_uart_bytes_written();
   job->slot = ota_uart_target_slot();
+  uint32_t uart_total = ota_uart_total_size();
 
   bool success = false;
   esp_err_t err = ota_uart_finish(false, &success);
   if (err != ESP_OK || !success) {
-    send_ota_status(OTA_UART_ST_FAILED, (uint32_t)err);
+    send_ota_failed((uint32_t)err);
     free(job);
     return;
   }
 
+  if (uart_total > 0) {
+    led_ring_show_ota_progress(job->written, uart_total, OTA_LED_UART_R,
+                               OTA_LED_UART_G, OTA_LED_UART_B);
+  }
+
   if (xTaskCreate(ota_distribute_task, "ota_dist", OTA_DIST_STACK, job,
                   OTA_DIST_PRIO, NULL) != pdPASS) {
     ESP_LOGE(TAG, "failed to create ota_dist task");
-    send_ota_status(OTA_UART_ST_FAILED, 22);
+    send_ota_failed( 22);
     free(job);
   }
 }
@@ -253,26 +298,26 @@ static void handle_ota_start_espnow(const uint8_t *data, size_t len) {
   (void)len;
 
   if (ota_uart_is_active()) {
-    send_ota_status(OTA_UART_ST_FAILED, 40);
+    send_ota_failed( 40);
     return;
   }
 
   const esp_partition_t *part = NULL;
   uint32_t image_size = 0;
   if (!ota_uart_get_staged_image(&part, &image_size)) {
-    send_ota_status(OTA_UART_ST_FAILED, 41);
+    send_ota_failed( 41);
     return;
   }
 
   esp_err_t   err = ota_espnow_distribute(part, image_size, &s_dist_progress);
   if (err != ESP_OK) {
-    send_ota_status(OTA_UART_ST_FAILED, 42);
+    send_ota_failed( 42);
     return;
   }
 
   err = ota_uart_apply_boot();
   if (err != ESP_OK) {
-    send_ota_status(OTA_UART_ST_FAILED, (uint32_t)err);
+    send_ota_failed( (uint32_t)err);
     return;
   }
 
@@ -283,6 +328,7 @@ static void handle_ota_start_espnow(const uint8_t *data, size_t len) {
   response.payload.ota_status.bytes_written = image_size;
   response.payload.ota_status.error = 0;
   uart_cmd_send(&response, TAG);
+  led_ring_ota_success();
 }
 
 void cmd_ota_register(void) {

main/led_ring.c

@@ -3,6 +3,8 @@
 #include "driver/i2c_types.h"
 #include "esp_err.h"
 #include "esp_log.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
 #include "led_strip.h"
 #include <stdint.h>
 
@@ -16,6 +18,8 @@ static led_strip_handle_t led_ring;
 
 #define RING_LEDS 95
 #define LED_RING_PIN 7
+#define LED_RING_BLINK_ON_MS 350
+#define LED_RING_BLINK_OFF_MS 150
 
 static QueueHandle_t led_queue;
 
@@ -43,20 +47,33 @@ const uint8_t d9[] = {19, 20, 21, 22, 23, 24, 25, 26, 27, 46, 47, 58,
 const uint8_t d10[] = {46, 50, 57, 61, 65, 72, 76, 78, 80,
                        82, 84, 86, 88, 90, 92, 93, 94, 95};
 
-// Lookup Array for the Digits
 const digit_definition_t digit_lookup[] = {
     {d0, sizeof(d0)}, {d1, sizeof(d1)}, {d2, sizeof(d2)},  {d3, sizeof(d3)},
     {d4, sizeof(d4)}, {d5, sizeof(d5)}, {d6, sizeof(d6)},  {d7, sizeof(d7)},
     {d8, sizeof(d8)}, {d9, sizeof(d9)}, {d10, sizeof(d10)}};
 
+void led_ring_scale_rgb(uint8_t *r, uint8_t *g, uint8_t *b, uint8_t intensity) {
+  if (intensity == 0) {
+    intensity = LED_RING_DEFAULT_INTENSITY;
+  }
+  *r = (uint16_t)(*r) * intensity / 255;
+  *g = (uint16_t)(*g) * intensity / 255;
+  *b = (uint16_t)(*b) * intensity / 255;
+}
+
+static void ring_fill_color(uint8_t r, uint8_t g, uint8_t b) {
+  for (uint32_t i = 0; i < RING_LEDS; i++) {
+    led_strip_set_pixel(led_ring, i, r, g, b);
+  }
+}
+
 void vTaskLedRing(void *pvParameters) {
-  /* LED Ring config */
   led_strip_config_t ring_config = {
       .strip_gpio_num = LED_RING_PIN,
       .max_leds = RING_LEDS,
   };
   led_strip_rmt_config_t rmt_ring_config = {
-      .resolution_hz = 10 * 1000 * 1000, // 10 MHz
+      .resolution_hz = 10 * 1000 * 1000,
   };
   esp_err_t err =
       led_strip_new_rmt_device(&ring_config, &rmt_ring_config, &led_ring);
@@ -67,17 +84,19 @@ void vTaskLedRing(void *pvParameters) {
   led_command_t cmd;
   while (1) {
     if (xQueueReceive(led_queue, &cmd, portMAX_DELAY)) {
+      uint8_t r = cmd.r;
+      uint8_t g = cmd.g;
+      uint8_t b = cmd.b;
+      led_ring_scale_rgb(&r, &g, &b, cmd.intensity);
+
       led_strip_clear(led_ring);
 
       if (cmd.mode == LED_CMD_CLEAR) {
         /* ring already cleared */
       } else if (cmd.mode == LED_CMD_SET_DIGIT && cmd.value <= 10) {
         digit_definition_t digit = digit_lookup[cmd.value];
-
         for (int i = 0; i < digit.count; i++) {
-          // Invert LED Counting for Now
+          led_strip_set_pixel(led_ring, RING_LEDS - digit.leds[i], r, g, b);
-          led_strip_set_pixel(led_ring, RING_LEDS - digit.leds[i], cmd.r, cmd.g,
-                              cmd.b);
         }
       } else if (cmd.mode == LED_CMD_PROGRESS) {
         uint32_t lit = ((uint32_t)cmd.progress * RING_LEDS + 50) / 100;
@@ -85,8 +104,23 @@ void vTaskLedRing(void *pvParameters) {
           lit = RING_LEDS;
         }
         for (uint32_t i = 0; i < lit; i++) {
-          led_strip_set_pixel(led_ring, i, cmd.r, cmd.g, cmd.b);
+          led_strip_set_pixel(led_ring, i, r, g, b);
         }
+      } else if (cmd.mode == LED_CMD_BLINK) {
+        uint16_t on_ms = cmd.blink_ms > 0 ? cmd.blink_ms : LED_RING_BLINK_ON_MS;
+        uint8_t count = cmd.blink_count > 0 ? cmd.blink_count : 1;
+
+        for (uint8_t n = 0; n < count; n++) {
+          ring_fill_color(r, g, b);
+          led_strip_refresh(led_ring);
+          vTaskDelay(pdMS_TO_TICKS(on_ms));
+          led_strip_clear(led_ring);
+          led_strip_refresh(led_ring);
+          if (n + 1 < count) {
+            vTaskDelay(pdMS_TO_TICKS(LED_RING_BLINK_OFF_MS));
+          }
+        }
+        continue;
       }
       led_strip_refresh(led_ring);
     }
@@ -103,3 +137,61 @@ void led_ring_send_command(led_command_t *cmd) {
     xQueueSend(led_queue, cmd, portMAX_DELAY);
   }
 }
+
+void led_ring_show_ota_clear(void) {
+  led_command_t cmd = {.mode = LED_CMD_CLEAR};
+  led_ring_send_command(&cmd);
+}
+
+void led_ring_show_ota_progress(uint32_t bytes_done, uint32_t total_bytes,
+                                uint8_t r, uint8_t g, uint8_t b) {
+  static struct {
+    uint8_t pct;
+    uint8_t r, g, b;
+  } last = {255, 0, 0, 0};
+
+  if (total_bytes == 0) {
+    return;
+  }
+
+  uint32_t pct32 = (bytes_done * 100u + total_bytes / 2) / total_bytes;
+  if (pct32 > 100) {
+    pct32 = 100;
+  }
+  uint8_t pct = (uint8_t)pct32;
+
+  if (pct == last.pct && r == last.r && g == last.g && b == last.b) {
+    return;
+  }
+  last.pct = pct;
+  last.r = r;
+  last.g = g;
+  last.b = b;
+
+  led_command_t cmd = {
+      .mode = LED_CMD_PROGRESS,
+      .progress = pct,
+      .r = r,
+      .g = g,
+      .b = b,
+      .intensity = LED_RING_DEFAULT_INTENSITY,
+  };
+  led_ring_send_command(&cmd);
+}
+
+void led_ring_blink_once(uint8_t r, uint8_t g, uint8_t b) {
+  led_command_t cmd = {
+      .mode = LED_CMD_BLINK,
+      .r = r,
+      .g = g,
+      .b = b,
+      .intensity = LED_RING_DEFAULT_INTENSITY,
+      .blink_ms = LED_RING_BLINK_ON_MS,
+      .blink_count = 1,
+  };
+  led_ring_send_command(&cmd);
+}
+
+void led_ring_ota_success(void) { led_ring_blink_once(0, 255, 0); }
+
+void led_ring_ota_failed(void) { led_ring_blink_once(255, 0, 0); }

main/led_ring.h

@@ -1,10 +1,17 @@
+#ifndef LED_RING_H
+#define LED_RING_H
+
 #include <stdint.h>
 
+/** Default RGB scale (~5 % of full brightness). */
+#define LED_RING_DEFAULT_INTENSITY 13
+
 typedef enum {
   LED_CMD_CLEAR,
   LED_CMD_SET_DIGIT,
   LED_CMD_SET_COLOR,
-  LED_CMD_PROGRESS
+  LED_CMD_PROGRESS,
+  LED_CMD_BLINK
 } led_mode_t;
 
 typedef struct {
@@ -13,7 +20,23 @@ typedef struct {
   uint8_t r, g, b;
   uint8_t intensity;
   uint8_t progress;
+  uint16_t blink_ms;
+  uint8_t blink_count;
 } led_command_t;
 
 void led_ring_send_command(led_command_t *cmd);
 void led_ring_init(void);
+
+void led_ring_scale_rgb(uint8_t *r, uint8_t *g, uint8_t *b, uint8_t intensity);
+
+/** OTA feedback: ring fill 0–100 % with RGB. */
+void led_ring_show_ota_progress(uint32_t bytes_done, uint32_t total_bytes,
+                                uint8_t r, uint8_t g, uint8_t b);
+void led_ring_show_ota_clear(void);
+
+/** Single pulse on the full ring (blocking in LED task). */
+void led_ring_blink_once(uint8_t r, uint8_t g, uint8_t b);
+void led_ring_ota_success(void);
+void led_ring_ota_failed(void);
+
+#endif

main/ota_espnow.c

@@ -1,5 +1,6 @@
 #include "ota_espnow.h"
 #include "app_config.h"
+#include "led_ring.h"
 #include "client_registry.h"
 #include "esp_log.h"
 #include "esp_now_comm.h"
@@ -27,6 +28,11 @@ static const char *TAG = "[OTA_ESPNOW]";
 #define OTA_ST_SUCCESS 4u
 #define OTA_ST_FAILED 5u
 
+/** ESP-NOW OTA receive on slave (blue progress bar). */
+#define OTA_LED_ESPNOW_RX_R 0
+#define OTA_LED_ESPNOW_RX_G 0
+#define OTA_LED_ESPNOW_RX_B 255
+
 #define OTA_MAX_TARGETS CLIENT_REGISTRY_MAX
 
 static EventGroupHandle_t s_eg;
@@ -170,6 +176,8 @@ static void ota_slave_prepare_task(void *param) {
   }
 
   send_slave_status(master_mac, OTA_ST_READY, 0, 0);
+  led_ring_show_ota_progress(0, total_size, OTA_LED_ESPNOW_RX_R, OTA_LED_ESPNOW_RX_G,
+                             OTA_LED_ESPNOW_RX_B);
   vTaskDelete(NULL);
 }
 
@@ -214,13 +222,27 @@ void ota_espnow_slave_on_payload(const uint8_t master_mac[6],
   ota_feed_result_t r =
       ota_uart_feed(payload->data.bytes, payload->data.size);
   if (r == OTA_FEED_ERROR) {
+    led_ring_ota_failed();
     send_slave_status(master_mac, OTA_ST_FAILED, ota_uart_bytes_written(), 13);
     return;
   }
   if (r == OTA_FEED_BLOCK_WRITTEN) {
     uint32_t written = ota_uart_bytes_written();
+    uint32_t total = ota_uart_total_size();
     ESP_LOGI(TAG, "block written %lu bytes -> ack master", (unsigned long)written);
+    led_ring_show_ota_progress(written, total, OTA_LED_ESPNOW_RX_R, OTA_LED_ESPNOW_RX_G,
+                               OTA_LED_ESPNOW_RX_B);
     send_slave_status(master_mac, OTA_ST_BLOCK_ACK, written, 0);
+    return;
+  }
+
+  if (r == OTA_FEED_OK) {
+    uint32_t total = ota_uart_total_size();
+    if (total > 0) {
+      led_ring_show_ota_progress(ota_uart_bytes_received(), total,
+                                 OTA_LED_ESPNOW_RX_R, OTA_LED_ESPNOW_RX_G,
+                                 OTA_LED_ESPNOW_RX_B);
+    }
   }
 }
 
@@ -235,11 +257,13 @@ void ota_espnow_slave_on_end(const uint8_t master_mac[6]) {
   bool success = false;
   esp_err_t err = ota_uart_finish(true, &success);
   if (err != ESP_OK || !success) {
+    led_ring_ota_failed();
     send_slave_status(master_mac, OTA_ST_FAILED, written, (uint32_t)err);
     return;
   }
 
   send_slave_status(master_mac, OTA_ST_SUCCESS, written, 0);
+  led_ring_ota_success();
   ESP_LOGI(TAG, "slave OTA success (%lu bytes), reboot to run",
            (unsigned long)written);
 }

main/ota_uart.c

@@ -151,6 +151,10 @@ ota_feed_result_t ota_uart_feed(const uint8_t *data, size_t len) {
 
 uint32_t ota_uart_bytes_written(void) { return s_ota.written; }
 
+uint32_t ota_uart_bytes_received(void) { return s_ota.received; }
+
+uint32_t ota_uart_total_size(void) { return s_ota.active ? s_ota.total_size : 0; }
+
 bool ota_uart_get_staged_image(const esp_partition_t **partition_out,
                                uint32_t *size_out) {
   if (!s_staged.valid || s_staged.partition == NULL) {

main/ota_uart.h

@@ -46,6 +46,12 @@ ota_feed_result_t ota_uart_feed(const uint8_t *data, size_t len);
 
 uint32_t ota_uart_bytes_written(void);
 
+/** Bytes accepted in the current session (includes buffered block). */
+uint32_t ota_uart_bytes_received(void);
+
+/** Image size from OTA_START / ESP-NOW OTA_START; 0 if inactive. */
+uint32_t ota_uart_total_size(void);
+
 /**
  * Flush remainder and esp_ota_end. When set_boot is false, the staged image
  * remains readable via ota_uart_get_staged_image() until ota_uart_apply_boot().

main/proto/uart_messages.pb.h

@@ -96,8 +96,8 @@ typedef struct _alox_EspNowUnicastTestResponse {
     uint32_t seq;
 } alox_EspNowUnicastTestResponse;
 
-/* Host → device: LED ring display (progress bar, digit, or clear).
+/* Host → device: LED ring display (progress bar, digit, clear, or blink).
- mode: 0=clear, 1=progress (0–100 %), 2=digit (0–10, same layout as firmware digit maps). */
+ mode: 0=clear, 1=progress (0–100 %), 2=digit (0–10), 3=blink full ring. */
 typedef struct _alox_LedRingProgressRequest {
     uint32_t mode;
     /* * 0–100: fraction of ring LEDs to light (mode=progress) */
@@ -107,8 +107,12 @@ typedef struct _alox_LedRingProgressRequest {
     uint32_t r;
     uint32_t g;
     uint32_t b;
-    /* * 0–255 brightness scale applied to r/g/b */
+    /* * 0–255 brightness scale; 0 = firmware default (~5 %) */
     uint32_t intensity;
+    /* * Pulse length in ms (mode=blink, default 350) */
+    uint32_t blink_ms;
+    /* * Number of pulses (mode=blink, default 1) */
+    uint32_t blink_count;
 } alox_LedRingProgressRequest;
 
 typedef struct _alox_LedRingProgressResponse {
@@ -237,7 +241,7 @@ extern "C" {
 #define alox_AccelDeadzoneResponse_init_default  {0, 0, 0, 0}
 #define alox_EspNowUnicastTestRequest_init_default {0, 0}
 #define alox_EspNowUnicastTestResponse_init_default {0, 0}
-#define alox_LedRingProgressRequest_init_default {0, 0, 0, 0, 0, 0, 0}
+#define alox_LedRingProgressRequest_init_default {0, 0, 0, 0, 0, 0, 0, 0, 0}
 #define alox_LedRingProgressResponse_init_default {0, 0, 0, 0}
 #define alox_OtaStartPayload_init_default        {0}
 #define alox_OtaPayload_init_default             {0, {0, {0}}}
@@ -258,7 +262,7 @@ extern "C" {
 #define alox_AccelDeadzoneResponse_init_zero     {0, 0, 0, 0}
 #define alox_EspNowUnicastTestRequest_init_zero  {0, 0}
 #define alox_EspNowUnicastTestResponse_init_zero {0, 0}
-#define alox_LedRingProgressRequest_init_zero    {0, 0, 0, 0, 0, 0, 0}
+#define alox_LedRingProgressRequest_init_zero    {0, 0, 0, 0, 0, 0, 0, 0, 0}
 #define alox_LedRingProgressResponse_init_zero   {0, 0, 0, 0}
 #define alox_OtaStartPayload_init_zero           {0}
 #define alox_OtaPayload_init_zero                {0, {0, {0}}}
@@ -305,6 +309,8 @@ extern "C" {
 #define alox_LedRingProgressRequest_g_tag        5
 #define alox_LedRingProgressRequest_b_tag        6
 #define alox_LedRingProgressRequest_intensity_tag 7
+#define alox_LedRingProgressRequest_blink_ms_tag 8
+#define alox_LedRingProgressRequest_blink_count_tag 9
 #define alox_LedRingProgressResponse_success_tag 1
 #define alox_LedRingProgressResponse_mode_tag    2
 #define alox_LedRingProgressResponse_progress_tag 3
@@ -469,7 +475,9 @@ X(a, STATIC,   SINGULAR, UINT32,   digit,             3) \
 X(a, STATIC,   SINGULAR, UINT32,   r,                 4) \
 X(a, STATIC,   SINGULAR, UINT32,   g,                 5) \
 X(a, STATIC,   SINGULAR, UINT32,   b,                 6) \
-X(a, STATIC,   SINGULAR, UINT32,   intensity,         7)
+X(a, STATIC,   SINGULAR, UINT32,   intensity,         7) \
+X(a, STATIC,   SINGULAR, UINT32,   blink_ms,          8) \
+X(a, STATIC,   SINGULAR, UINT32,   blink_count,       9)
 #define alox_LedRingProgressRequest_CALLBACK NULL
 #define alox_LedRingProgressRequest_DEFAULT NULL
 
@@ -588,7 +596,7 @@ extern const pb_msgdesc_t alox_OtaSlaveProgressResponse_msg;
 #define alox_ClientInput_size                    22
 #define alox_EspNowUnicastTestRequest_size       12
 #define alox_EspNowUnicastTestResponse_size      8
-#define alox_LedRingProgressRequest_size         42
+#define alox_LedRingProgressRequest_size         54
 #define alox_LedRingProgressResponse_size        20
 #define alox_OtaEndPayload_size                  0
 #define alox_OtaPayload_size                     209

main/proto/uart_messages.proto

@@ -110,8 +110,8 @@ message EspNowUnicastTestResponse {
   uint32 seq = 2;
 }
 
-// Host → device: LED ring display (progress bar, digit, or clear).
+// Host → device: LED ring display (progress bar, digit, clear, or blink).
-// mode: 0=clear, 1=progress (0–100 %), 2=digit (0–10, same layout as firmware digit maps).
+// mode: 0=clear, 1=progress (0–100 %), 2=digit (0–10), 3=blink full ring.
 message LedRingProgressRequest {
   uint32 mode = 1;
   /** 0–100: fraction of ring LEDs to light (mode=progress) */
@@ -121,8 +121,12 @@ message LedRingProgressRequest {
   uint32 r = 4;
   uint32 g = 5;
   uint32 b = 6;
-  /** 0–255 brightness scale applied to r/g/b */
+  /** 0–255 brightness scale; 0 = firmware default (~5 %) */
   uint32 intensity = 7;
+  /** Pulse length in ms (mode=blink, default 350) */
+  uint32 blink_ms = 8;
+  /** Number of pulses (mode=blink, default 1) */
+  uint32 blink_count = 9;
 }
 
 message LedRingProgressResponse {