#define CLK 2
#define ENCODER  3
int counter=0;

void setup() {
  Serial.begin(115200);
  pinMode(CLK, INPUT);
  pinMode(ENCODER, INPUT);
}

int lastClk = HIGH;

void loop() {
  int newClk = digitalRead(CLK);
  if (newClk != lastClk) {

    lastClk = newClk;
    int dtValue = digitalRead(ENCODER);
    if (newClk == LOW && dtValue == HIGH) {

      counter++ ; if(counter > 10){counter = 10;}
      Serial.println(counter);
    }
    if (newClk == LOW && dtValue == LOW) {

      counter--; if(counter < 0){counter = 0;}
      Serial.println(counter);
    }
  }
}