 
 // command packet - start, address, data length, command, data[0 to 2], end
 // response packet when idle - 0xAA, 0x00, 0x02, 0x01, 0x83, 0x80, 0xBB
-const int ledPin = 13;
-const int signalPin = 4;
 char get_readID[] = { 0xAA , 0x00, 0x03, 0x25, 0x26, 0x00, 0x00, 0xBB };
 byte response[11];
 bool standby;
 unsigned long elapsed_time;
+const int ledPin = 13;
+const int signalPin = 4;
 
 void setup() {
   Serial.begin(57600);


unsigned long accumulator(bool standby) {
  unsigned long startTime, endTime = 0;
  int signalState, previousState = 0;
  
  while(!standby) {
    // read signal state

/* RFID Reader
   Uses RDM880 breakout board with RX connected to pin 2 and TX connected to pin 3. 
   Another serial interface is added by including the Software Serial library.
   Dummy signal from 3.3 V is connected to pin 4.

   Input:
      RFID tag
