INT 14 - PC-MOS/386 v5.01 $serial.sys v5.04 - RECEIVE CHARACTER, WITH TIMEOUT
        AH = 22h
        DX = port number
        SI = timeout in timer ticks (0000h = default)
Return: AH = port status (see AH=03h bits 0..6)
             bit 7 = 1 indicates time-out
        AL = character received
Program: PC-MOS/386 v5.01 is a multitasking, multiuser MS-DOS 5.0-compatible
          operating system by The Software Link, Inc.
SeeAlso: AH=02h,AH=0Fh"PC-MOS",AH=21h"PC-MOS"

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