Beat 0 (first beat after START) full white, subsequent beats dimmer — marks bar downbeat

src/main.cpp

@@ -29,6 +29,7 @@ void midi_task(void* parameter) {
     // Beat timing fixes for precise beat alignment - sync to real MIDI time, not hardcoded tempo
     uint32_t last_beat = UINT32_MAX;
     uint32_t flash_start = 0;
+    uint8_t flash_peak = 255;
 
     while (true) {
         midi_transport.update();
@@ -45,7 +46,14 @@ void midi_task(void* parameter) {
         if (current_beat != last_beat) {
             last_beat = current_beat;
             flash_start = now;
-            mux.set_led_color(6, 255, 255, 255);
+            // First beat after each START is beat 1 (downbeat) — full white
+            // Loopy Pro sends START at bar boundaries so this is always beat 1
+            if (current_beat == 0) {
+                flash_peak = 255;
+            } else {
+                flash_peak = 64;
+            }
+            mux.set_led_color(6, flash_peak, flash_peak, flash_peak);
             mux.show();
         }
 
@@ -58,7 +66,7 @@ void midi_task(void* parameter) {
                 flash_start = 0;
             } else {
                 float b = 1.0f - (float)elapsed / 80.0f;
-                uint8_t v = (uint8_t)(255 * b * b);
+                uint8_t v = (uint8_t)((float)flash_peak * b * b);
                 mux.set_led_color(6, v, v, v);
                 mux.show();
             }