Function 2Dh Set Time
Sets current system time
entry AH 2Dh
CH hours (0-23)
CL minutes (0-59)
DH seconds (0-59)
DL hundredths of seconds (0-99)
return AL 00h if no error
0FFh if bad value sent to routine
note 1) DOS 3.3 also sets CMOS clock
2) CX and DX must contain a valid time in binary