Function  0Ch   Clear Keyboard Buffer & Invoke a Keyboard Function       (FCB) 
      Dumps buffer, executes function in AL (01h,06h,07h,08h,0Ah only) 
entry   AH      0Ch 
	AL      function number (must be 01h, 06h, 07h, 08h, or 0Ah) 
return  AL      00h     buffer was flushed, no other processing performed 
		other   any other value has no meaning 
note 1) Forces system to wait until a character is typed.  
     2) Flushes all typeahead input, then executes function specified by AL (by 
	moving it to AH and repeating the int 21 call). 
     3) If AL contains a value not in the list above, the keyboard buffer is 
	flushed and no other action is taken.