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MODULAR SMART SWITCH
5. Installing the Modular Smart Switch
5.1 Selecting Ports for Your Equipment
Printer and Plotter Sharing Applications
Unless otherwise specified, all print and plot data will automatically be routed
to port 1. If you are automatically sharing a single printer or plotter, connect
it to port 1. All ports have equal priority and data output is handled on a
“first-come-first-served” basis.
General Datacomm Applications
For applications involving a central controlling PC, the PC should normally
be connected to port 1 since data is routed to this port by default.
5.2 Positioning the Modular Smart Switch
Choose a central position for the Modular Smart Switch. This keeps cable
lengths to a minimum.
5.3 Cable Requirements
You will need a suitable cable for each device that you wish to connect to the
switch. Mechanical and electrical specifications for the cables are given in
Appendix A
(serial) and
Appendix B
(parallel).
NOTE
A great number of serial cables are available that are not suitable for use
with your Modular Smart Switch. Do not assume that an existing cable is
of the correct type because it has the correct connectors on each end or
because it works between two other pieces of equipment. Always use
the cabling recommended in this manual.
Centronics parallel cables should be less than 22.9 ft. (7 m) long. If the
parallel computer or printer is more than 22.9 ft. (7 m) from the switch, the
cable may be susceptible to spurious pick-up such as that generated from
switching on fluorescent lights. Reduce the cable runs or use a booster if you
have problems.
5.4 Connecting Devices to the Modular Smart Switch
Switch off all computers and printers before making any connections to the
Modular Smart Switch. Also, park any hard disks if you need to move any PCs
to allow access.
20
MODULAR SMART SWITCH
Figure 4-3. Setting Serial Port Options and Protocols.
OFF
(0)
ON
(1)
1
ON
2
3
4
5
6
7
8
9 10
1 0 1
1 1 1
0
0
0
0
0
1
0
1
1
0 1 0
1 0 0
1 1 0
57k6 baud
38k4 baud
19k2 baud
9k6 baud
4k8 baud
2k4 baud
1k2 baud
300 baud
0
1
RS422
RS232
XON/XOFF-printer/plotter connections
0
0
1
0
1
1
1 0
XON/XOFF-computer connections
ETX/ACK handshake
DTR/CTS handshake
0
1
7 bits
8 bits
0
1
2 stop bits
1 stop bit
0
0
0
1
1 1
Even parity
Odd parity
No parity
HIGH port
Dual serial
port module
LOW port
HIGH port
switches
LOW port
switches