message: Adding a Tympan Rev E_A
diff: #ifndef _Tympan_h
  #define _Tympan_h
  -enum class TympanRev { A, C, D, D0, D1, D2, D3, D4 };
  +enum class TympanRev { A, C, D, D0, D1, D2, D3, D4, E_A };
  //constants to help define which version of Tympan is being used
  #define TYMPAN_REV_A (TympanRev::A)
  @@ -117,6 +117,18 @@ class TympanPins { //Teensy 3.6 Pin Numbering
  BT_serial_speed = 9600;
  Rev_Test = 44;
  break;
  + case (TympanRev::E_A) : //Earliest trials with Tympan 4 with Rev A
  + //Teensy 4.0 Pin Numbering
  + resetAIC = 5; //PTD6
  + potentiometer = 15; //PTC0
  + amberLED = 36; //PTC9
  + redLED = 35; //PTC8
  + BT_nReset = 6; //
  + BT_REGEN = NOT_A_FEATURE;
  + BT_PIO4 = 2; //PTD0
  + reversePot = true;
  + enableStereoExtMicBias = NOT_A_FEATURE; //mic jack is already stereo, can't do mono.
  + break;
  }
  }
  usb_serial_class * getUSBSerial(void) { return USB_Serial; }
  