encoder

  int value = 0;

void setup() {
  Serial.begin(115200);
  pinMode(2, INPUT_PULLUP);
  pinMode(3, INPUT_PULLUP);
  pinMode(5, OUTPUT);
  check();
}
void check() {
  value = constrain(value, 0, 255);
  analogWrite(5, value);
  Serial.println(value);
  if (digitalRead(2)==LOW && digitalRead(3)==HIGH) {
    up();
  }

  else if (digitalRead(3)==LOW && digitalRead(2)==HIGH) {
    down();
    }
    else {
      check();
    }
  }

void up(){
  if (digitalRead(2)==HIGH && digitalRead(3)==HIGH){
    value=value+10;
    check();
  }
  else{
    up();
  }
}
void down(){
  if (digitalRead(3)==HIGH && digitalRead(2)==HIGH) {
    value=value-10;
    check();
  }
  else {
    down();
  }
}

void loop() {
}