diff --git a/src/main.c b/src/main.c
index ab125f0..b3a26fd 100644
--- a/src/main.c
+++ b/src/main.c
@@ -113,6 +113,7 @@ static struct mgmt_callback dfu_status_callback = {
     .callback = dfu_status_cb,
     .event_id = MGMT_EVT_OP_IMG_MGMT_DFU_STARTED |
                 MGMT_EVT_OP_IMG_MGMT_DFU_CHUNK |
+                MGMT_EVT_OP_IMG_MGMT_DFU_CHUNK_WRITE_COMPLETE |
                 MGMT_EVT_OP_IMG_MGMT_DFU_PENDING |
                 MGMT_EVT_OP_IMG_MGMT_DFU_STOPPED,
 };
@@ -553,7 +554,7 @@ static void dfu_watchdog_handler(struct k_work *work)
 
     if (ble_is_connected())
     {
-        DBG_PRINTF("[DFU] upload stalled (%ds), forcing disconnect\r\n", DFU_STALL_TIMEOUT_SEC);
+        DBG_CORE("[DFU] upload stalled (%ds), forcing disconnect\r\n", DFU_STALL_TIMEOUT_SEC);
         (void)ble_disconnect_active();
     }
 }
@@ -571,9 +572,10 @@ static enum mgmt_cb_return dfu_status_cb(uint32_t event, enum mgmt_cb_return pre
     {
         case MGMT_EVT_OP_IMG_MGMT_DFU_STARTED:
         case MGMT_EVT_OP_IMG_MGMT_DFU_CHUNK:
+        case MGMT_EVT_OP_IMG_MGMT_DFU_CHUNK_WRITE_COMPLETE:
             dfu_led_active = true;
             led_ble_solid(); // DFU 업로드 중에는 초록 LED ON
-            // 청크가 올 때마다 무진행 감시 타이머 리셋
+            // 청크 수신/flash write 완료 때마다 무진행 감시 타이머 리셋
             k_work_reschedule(&dfu_watchdog_work, K_SECONDS(DFU_STALL_TIMEOUT_SEC));
             break;