diff --git a/src/libty/class_teensy.c b/src/libty/class_teensy.c
index 9ffd7da..6f2b40c 100644
--- a/src/libty/class_teensy.c
+++ b/src/libty/class_teensy.c
@@ -333,6 +333,7 @@ static int teensy_open_interface(ty_board_interface *iface)
         case HS_DEVICE_TYPE_HID: {
             static const unsigned char seremu_magic[] = {0, 0xAB, 0xBA, 0xCD, 0xDC};
 
+            /* Signal SEREMU readiness to the Teensy */
             r = (int)hs_hid_send_feature_report(iface->port, seremu_magic, sizeof(seremu_magic));
             if (r < 0)
                 return ty_libhs_translate_error(r);