 
 #define TONE_PIN          2     // TIOA0
 #define PIN_LED1          13    // internal LED for showing AOA status.
-#define PIN_LED2          54    // external LED for showing serial input.
+#define PIN_LED2          54    // aka A0. external LED for showing serial input.
 #define TONE1600hz        1600 
 #define TONE400hz         400
 #define PULSE_TONE        1


// Min airspeed in knots before the audio tone is turned on
// This is useful because if your on the ground you don't need a beeping in your ear.
#define MUTE_AUDIO_UNDER_IAS  35

// dynon expected string length
#define DYNON_SERIAL_LEN      53

  // show audio muted and debug info.
  sprintf(tempBuf, "AUDIO MUTED: Airspeed to low. Min:%i ASI:%i",MUTE_AUDIO_UNDER_IAS, ASI);
  Serial.println(tempBuf);
  toneMode = TONE_OFF;
  return;
#endif
  }
  
