 #define CS_PIN 15
 #define RX_LED 17
 
+#define HEARTBEAT_TIMEOUT 2000
 #define KEY_TIMEOUT 100
 #define MOUSE_BASE_SPEED 8
 #define MOUSE_SPEEDUP 3
 
 #define SYN_FIELD 0x55
 #define SWM_ID 0x20
+#define HEARTBEAT_ID 0xCF
 
 // Volvo V50 2007 SWM key codes
 //

    mouseSpeed = MOUSE_BASE_SPEED;
  }
}

  digitalWrite(CS_PIN, HIGH);

  // Open serial communications to host (PC) and wait for port to open:
  Serial.begin(9600);
//  Serial.println("LIN Debugging begins");

  Serial1.begin(9600);
