[PC] [XT] [AT]
Expects: AH    00H
Returns: AL    0 if timer has not overflowed past 24 hrs since reset
CX,DX Ticks since last reset; CX is high, DX is low
Info: Obtains the current tick-count.  The tick count is stored at
0040:006E in the BIOS Data Area.  It is incremented about once
every 55 ms by INT 08H:

clock updates at 1193180/65536 (about 18.2) ticks per second.
counts per second   18
counts per minute   1092
counts per hour     65543
counts per day      1573040

See Also: INT 1aH (BIOS Time I/O)
DOS fn 2cH (get system time)
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INT 1aH 00H: Read System Clock (Ticks)