SCADA_Encoder.ino

 /* Read Quadrature Encoder
  * Connect Encoder to Pins encoder0PinA, encoder0PinB, and +5V.
  *
  * Sketch by max wolf / www.meso.net
  * v. 0.1 - very basic functions - mw 20061220
  *
  */  


 int val; 
 int encoder0PinA = 3;
 int encoder0PinB = 4;
 int encoder0Pos = 0;
 int encoder0PinALast = LOW;
 int n = LOW;

 void setup() { 
   pinMode (encoder0PinA,INPUT);
   pinMode (encoder0PinB,INPUT);
   Serial.begin (9600);
 } 

 void loop() { 
   n = digitalRead(encoder0PinA);
   if ((encoder0PinALast == LOW) && (n == HIGH)) {
     if (digitalRead(encoder0PinB) == LOW) {
       encoder0Pos--;
     } else {
       encoder0Pos++;
     }
     Serial.print (encoder0Pos);
     Serial.print ("/");
   } 
   encoder0PinALast = n;
 }