INT 14 - SERIAL - GET PORTIBM PC Portable (uses same BIOS as XT) STATUS
	AH = 03h
	AL = 00h (ArtiCom)
	DX = port number (00h-03h) (04h-43h for Digiboard XAPCM232.SYS)
Return: AH = line status (see #00304)
	AL = modem status (see #00305)
	AX = 9E00h if disconnected (ArtiCom)
Note:	the 1993/04/08 Compaq system ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs. uses only the low two bits of DX
SeeAlso: AH=00h,AH=07h"MultiDOS",AX=8000h"ARTICOM",AH=81h"COURIERS",AX=FD02h


Bitfields for serial line status:
Bit(s)	Description	(Table 00304)
 7	timeout
 6	transmit shift register empty
 5	transmit holding register empty
 4	break detected
 3	framing error
 2	parity error
 1	overrun error
 0	receive data ready
Note:	for COMM-DRV, if bit 7 is set, an error occurred, and may be retrieved
	  through a separate call (see AX=8000h"COMM-DRV")


Bitfields for modem status:
Bit(s)	Description	(Table 00305)
 7	carrier detect
 6	ring indicator
 5	data set ready
 4	clear to send
 3	delta carrier detect
 2	trailing edge of ring indicator
 1	delta data set ready
 0	delta clear to send