//#include <Arduino.h>
// constants
const int PinCLK = 25; // Used for generating interrupts using CLK signal
const int PinDT = 12; // Used for reading DT signal
const int PinSW = 14; // Used for the push button switch


// global vars
volatile int virtualPosition = 0;

// forward decls
// void isr();
// void loop();
// void setup();

// Interrupt service routine is executed when a HIGH to LOW transition is detected on CLK
// void isr () {

// if (!digitalRead(PinDT) )

// virtualPosition = virtualPosition + 1;
// else
// virtualPosition = virtualPosition - 1;
// } // isr

void isr () {
static unsigned long lastInterruptTime = 0;
unsigned long interruptTime = millis();
// If interrupts come faster than 5ms, assume it's a bounce and ignore
if (interruptTime - lastInterruptTime > 5) {
if (!digitalRead(PinDT) )
virtualPosition = (virtualPosition + 1);
else
virtualPosition = virtualPosition - 1;
}
lastInterruptTime = interruptTime;
} // ISR

//------------------
void setup() {
Serial .begin (9600);
pinMode (PinCLK, INPUT) ;
pinMode (PinDT, INPUT);
pinMode (PinSW, INPUT);
attachInterrupt(25, isr, FALLING); // interrupt 0 is always connected to pin 2 on Arduino UNO
Serial.println ("Start");
} // setup
//-------------------------

void loop() {
int lastCount = 0;
while (true) {
if (!(digitalRead(PinSW))) { // check if pushbutton is pressed
virtualPosition = 0; // if YES, then reset counter to ZERO
while (!digitalRead(PinSW)) {} // wait til switch is released
delay (10); // debounce
Serial.println ("Reset") ; // Using the word RESET instead of COUNT here to find out a buggy encoder
}
if (virtualPosition != lastCount) {
lastCount = virtualPosition;
Serial.print ("Count = ");
Serial.println (virtualPosition) ;
}
} // while
} //loop



//void isr () {
//static unsigned long lastInterruptTime = 0;
//unsigned long interruptTime = millis();
//// If interrupts come faster than 5ms, assume it's a bounce and ignore
//if (interruptTime - lastInterruptTime > 5) {
//if (!digitalRead(PinDT) )
//virtualPosition = (virtualPosition + 1);
//else
//virtualPosition = virtualPosition - 1;
//}
//lastInterruptTime = interruptTime;
//} // ISR