Example arduino sketch sending and receiving data via serial

ArduinoSerialSendReceive.c

char msg = '0';

void setup() {    
  Serial.begin(9600);  
}  
  
void loop(){  
  // While data is sent over serial assign it to the msg  
  while (Serial.available() > 0){  
      msg = Serial.read();  
  }
  
  // see what value is given out 
  if (msg != '0') {
    Serial.print(msg);
    //Serial.print(msg, BYTE);
    msg = '0';
  }  
}