How to get the buzzer work after storing Serial.read()?

Projects Programming
3

Its always an error to read more characters than are available:

  while(Serial.available()) {
    char inChar = Serial.read();  //if comment this 1
    inData[index] = inChar;        // and this 2
    index++;  
    inString += inChar;               //and this 3, buzzer will beep
    if (Serial.read() == 13) { // \r cannot be detected if I were to use buzzer. Use 13

should be changed to something like this:

  while(Serial.available()) {  // pass this test, at least 1 char is available.
    char inChar = Serial.read();
    if (index < MAXCHARS)  // check for buffer over-run.
    {
      inData[index++] = inChar;
    }
    inString += inChar;  // why use string and String?
    if (inChar == 13) { // compare the character actually read

and change

char inData[] = "";

to

#define MAXCHARS 50  // or whatever is sensible
char inData[MAXCHARS+1] ;