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1257 User Manual
EADS North America Defense
Computer Interfaces 4-15
Test and Services, Inc.
©
2001
•
RS-232 cable, 10 ft. (3.05 meter)
P/N 602248
This cable has a DB-9 connector at each end. The male connector
connects to the 1257 and the female connector connects to the
data terminal or computer.
If you wish to make your own cable,
Figure 4-4a
provides the
details.
Figure 4-3, Using the RS-232 Interface
Connecting to a
Modem
If you wish to connect the 1257 directly to a modem instead of a
computer or data terminal, the connection will be DCE-to-DCE. A
DCE-to-DCE connection requires a special serial cable, known as
a null-modem. In a null-modem cable, the Received Data (RxD)
and Transmitted Data (TxD) signals are reversed at one connector,
and the Clear-to-Send (CTS) and Request-to-Send (RTS) signals
are also reversed at one connector. This can be accomplished by
constructing a special nine-pin serial cable with the signals wired
as shown in
Figure 4-4b, Using the 1257 with a Modem
. Note
that the RS-232 connector at the 1257 is a 9-pin female
D-Subminiature (DB-9) type.
RS-232 Connector
RS-232 Cable
RS-232
Interface
Connector