const int redPin = 2 ; const int yellowPin = 4 ; const int greenPin = 7 ; const int photoPin = A0 ; void setup() { boolean r; Serial.begin(9600); pinMode(redPin, OUTPUT); pinMode(greenPin, OUTPUT); pinMode(yellowPin, OUTPUT); } boolean ledState(boolean r,boolean y,boolean g){ digitalWrite(redPin, r); digitalWrite(yellowPin, y); digitalWrite(greenPin, g); } void loop(){ boolean r; // default to LED's off ledState(LOW,LOW,LOW); Serial.println(analogRead(photoPin)); if(analogRead(photoPin)>1000){ ledState(LOW,LOW,HIGH); } if(analogRead(photoPin)>975){ ledState(LOW,HIGH,LOW); } if(analogRead(photoPin)>950){ ledState(HIGH,LOW,LOW); } }