AT&T 6300 Programmer's Manual page 385

Syntax
n
speed
parity
OPEN COM
Statement
Opens a communications file.
OPEN "COMn:[speed][,parity][,data][,stop]
[,RS][,CS[n]] [,DS[n]][,CD[n]][,BIN] [,ACS]
[,LF]" AS [#] filenum [LEN =m]
is 1, 2, 3, or 4. It specifies the number of the Asynchronous Com-
munications Adapter.
is an integer constant that sets the transmit/receive baud rate
to one of the following speeds: 75, 110, 150,300,600, 1200, 1800,
2400, 4800, or 9600. The default is 300 bps.
designates the parity of the device to be OPENed:
E EVEN (default)
o
ODD
N NONE
M
S
MARK
(1)
SPACE
(0)
data
stop
RS
designates the number of data bits. Valid entries are 5, 6, 7, or
8. The default is 7.
designates the number of stop bits. Valid entries are 1, 1.5, or
2. Default is 2 for 75 bps and 110 bps, 1 for all other speeds.
suppresses the request-to-send (RTS) control character. If RS is
not used, RTS will be sent automatically as soon as the
communications line is OPENed.
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