INT 16h,  04h (4)        Adjust Keyboard Click              PCjr, Convertible
 
    Turns keyboard click on or off.
 
       On entry:      AH         04h
                      AL         0 - Turn keyboard click off
                                 1 - Turn keyboard click on
       Returns:       None
 
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       Notes:         This service is available only on the PCjr and the
                      PC Convertible.