Need help with code -serial

Thank you so much. You saved my life :smiley: :smiley:

int VstupA=3;
int VstupB=4;
int incomingByte = 0;   
String inString = ""; 
void setup() {
  
  pinMode(VstupA, OUTPUT);
  pinMode(VstupB, OUTPUT);
  Serial.begin(9600);     
}

void loop() {
  
  while (Serial.available() > 0) {
    incomingByte = Serial.read();
    inString += (char)incomingByte; 
  }
  if (inString == "X1"){ 
    digitalWrite(VstupA, HIGH); 
    Serial.print(" INPUT A:1");
    inString = ""; 
  }
  if (inString == "X0"){ 
    digitalWrite(VstupA, LOW); 
    Serial.print("INPUT A:0 ");
    inString = ""; 
  }
  if (inString == "Y1"){ 
    digitalWrite(VstupB, HIGH); 
    Serial.print(" INPUT B:1");
    
    inString = ""; 
  }
  if (inString == "Y0"){ 
    digitalWrite(VstupB, LOW); 
    Serial.print(" INPUT B:0");
    
    inString = ""; 
  }
}