ard.c

//sürücü  
  const int motorA1  = 5;
  const int motorA2  = 6;
  const int motorB1  = 10;
  const int motorB2  = 9;

  int i=0;
  int j=0;
  int state;
  int vSpeed=255;

void setup() {
    // Pin
    pinMode(motorA1, OUTPUT);
    pinMode(motorA2, OUTPUT);
    pinMode(motorB1, OUTPUT);
    pinMode(motorB2, OUTPUT);    
    // hız
    Serial.begin(9600);
}
 
void loop() {
     if(digitalRead(state)==LOW) { state='S'; }

    if(Serial.available() > 0){     
      state = Serial.read();   
    }
    if (state == '0'){
      vSpeed=0;}
    else if (state == '1'){
      vSpeed=100;}
    else if (state == '2'){
      vSpeed=180;}
    else if (state == '3'){
      vSpeed=200;}
    else if (state == '4'){
      vSpeed=255;}
     
  /*ileri*/
    if (state == 'F') {
      analogWrite(motorA1, vSpeed); analogWrite(motorA2, 0);
        analogWrite(motorB1, vSpeed);      analogWrite(motorB2, 0); 
    }
  /*geri*/
  //Gelen veri 'B' ise araba geri gider.
    else if (state == 'B') {
      analogWrite(motorA1, 0);   analogWrite(motorA2, vSpeed); 
        analogWrite(motorB1, 0);   analogWrite(motorB2, vSpeed); 
    }
  /*dur*/
  //Gelen veri 'S' ise arabayı durdur.
    else if (state == 'S'){
        analogWrite(motorA1, 0);  analogWrite(motorA2, 0); 
        analogWrite(motorB1, 0);  analogWrite(motorB2, 0);
    }  
}