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Int 14H Function 00H
◄Summary► ◄Notes► ◄Back►
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Description: Initialize Communications Port [PC] [AT] [PS/2]
Initializes a serial communications port to a desired baud rate, parity,
word length, and number of stop bits.
Input Output
═════════════════════════════ ═════════════════════════════════
AH=00H AH=port status
AL=initialization parameter Bit(s) Significance (if set)
(see Notes) ══════ ══════════════════════
DX=communications port number 7 timed-out
(0=COM1, 1=COM2, etc.) 6 transmit shift
register empty
5 transmit holding
register empty
4 break detected
3 framing error detected
2 parity error detected
1 overrun error detected
0 receive data ready
AL=modem status
Bit(s) Significance (if set)
══════ ══════════════════════
7 receive line signal
detect
6 ring indicator
5 data-set-ready
4 clear-to-send
3 change in receive line
signal detect
2 trailing edge ring
indicator
1 change in
data-set-ready status
0 change in
clear-to-send status
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