INT 14,4 - Serial Port Extended Initialization (PS/2 & later systems)

AH = 04

AL = break setting

BH = parity setting

BL = stop bit setting

CH = word length setting

CL = baud rate setting

DX = zero based serial port number (0-3)

% --- Break Setting ---

1 = break

0 = no break

% ----- Parity Setting ----- --- Stop Bit Setting ---

0 = no parity 0 = one stop bit

1 = odd parity 1 = 2 stop bits

2 = even parity 1½ if register CH=0

3 = stick parity odd (5 bit word length)

4 = stick parity even

% -- Word Length Setting -- ---- Baud rate Setting ----

0 = 5 bits 0 = 110 5 = 2400

1 = 6 bits 1 = 150 6 = 4800

2 = 7 bits 2 = 300 7 = 9600

3 = 8 bits 3 = 600 8 = 19200

4 = 1200

on return:

AH = port status

AL = modem status

- for status bits see ~INT 14,STATUS~