Chapter 2
Installing SCXI Modules and Connecting the SCXI System to the DAQ Device
2-6
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Using an RS-232 or RS-485 Serial Port
You can use the RS-232 port on your computer to control one chassis up to
100 ft from your computer. If your chassis is farther away or you are using
multiple chassis, you must use RS-485.
If you are using an SCXI-2400 module, insert the SCXI-2400 into the far
left slot of your SCXI-100X chassis and insert the SCXI-1200 module
immediately next to it. Attach the connector adapter that is shipped with the
SCXI-2400 module to the rear of the SCXI-2400. Connect the SCXI-1200
to this connector adapter using a 7 in. IEEE 1284 parallel port cable.
If you are using an SCXI-2000 chassis, insert the SCXI-1200 into the far
left slot of your SCXI chassis. Next, connect the 7 in. IEEE 1284 parallel
port cable to the back of the SCXI-1200 and the SCXI-2000 chassis.
Note
If your SCXI chassis includes only analog output and digital I/O modules, you do
not need the SCXI-1200 module. The SCXI-2000 and SCXI-2400 can communicate
directly with analog output and digital I/O modules.
Next, connect the SCXI-2000 or SCXI-2400 to an RS-232 or RS-485 port
of your computer.
•
RS-232—You can connect one SCXI chassis directly to the standard
COM serial port of your computer. If your computer has a 9-pin
communication port, use the 2 m null modem cable included with the
SCXI-2000/2400 to connect the 9-pin RS-232 connector on the front
panel of the SCXI-2000/2400 to the serial port of your computer.
•
RS-485—Alternatively, you can connect the RS-485 connectors on the
back of the SCXI-2000 chassis or SCXI-2400 module to an RS-485
network. For example, you can wire the RS-485 connector directly to
a port of the plug-in AT-485 adapter device. The RS-485 connection is
a four-wire connection. See your SCXI chassis user manual or
SCXI-2400 User Manual for more information on configuring an
RS-485 network.
