// Control for Model Railway Reversing Loop
// 4 sensors are read, 2 relais switch the rails to DCC A/B or B/A

void setup() {
  pinMode(2,OUTPUT); // relay 1
  pinMode(3,OUTPUT); // relay 2
  pinMode(4,INPUT_PULLUP); // sensor 1
  pinMode(5,INPUT_PULLUP); // sensor 2
  pinMode(6,INPUT_PULLUP); // sensor 3
  pinMode(7,INPUT_PULLUP); // sensor 4
}

void loop() {
  if (!digitalRead(4) || !digitalRead(5)) {digitalWrite (2, LOW); digitalWrite (3, LOW);}
  if (!digitalRead(6) || !digitalRead(7)) {digitalWrite (2, HIGH); digitalWrite (3, HIGH);}
}