Display message after key press?

[mike77]

Hi,
I need some helping hand.
I have to display each message only once when a key is pressed.
The problem in this code is that the message flickers/runs infinite loop.
How should I go about making it run only once every key press?

Thanks.

do { c = inportb(COM1 + 5);
	if (c & 1) {char = inportb(COM1);
		   
		  if (char == 79) // if O press
		  {	
                      clrscr();
		      printf("Letter O");
		   }
		   else if (char == 88)            //if X press
		   {
                      clrscr();
		      printf("Letter X");
		   }
		   else if (char == 89)          //if Y press
		   {
		      printf("Letter Y");
		      clrscr();
		   }
		   else if (char == 90)         //if Z press
		   {
                      clrscr();
		      printf("Letter Z");
		   }
	if (kbhit()){char = getch();	//if key pressed, get char
		    outportb(COM1, char);}	//send char to serial port
	} while (char !=27);	// if ESC pressed exit
  }