B&B Electronics 232BSS4 Manual page 21

Back to Back Operation (mux/demux)
Printer
PC
Printer
RF Modem
PC
Figure 2.2. Back to Back Operation
Two 232BSS4s can be connected together through their Master ports
to provide a simple form of multiplexer/demultiplexer. Any Slave port on
one switch can automatically send to one or more ports on the other over
the single Master port communication channel. The setup software walks
the user through the configuration and automatically sets the Slave port
preambles.
When two 232BSS4s are connected for Back to Back operation, the
Slave ports would typically be set up for a slower baud rate than the Master
ports. If the Master ports will not be running at a baud rate at least four
times the speed of the Slaves, or if the main Master channel will be
connected over a slow communications channel such as through modems,
all ports should be configured through the setup software to use hardware
handshaking.
Hardware handshaking is automatically turned on for the Master ports
when you configure the switches for back to back operation. If you are
operating the switches with a direct cable connection or if your
communications link does not require handshaking, this option can be
turned off in the single unit configuration setup. For details on how to use
the setup software, see Chapter 4.
Note that in Back to Back operation the 232BSS4 Master ports will
normally be connected to either the Master port of another switch or some
type of modem. Because the Master ports are almost always connected to
another DCE device, a null modem cable will probably be required. Refer
to the cable charts in Appendix B for connecting the Master port to another
DCE port.
Documentation Number 232BSS4-2907m
&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 – www.bb-elec.com
B&B Electronics – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445 – www.bb-europe.com
Direct Cable Connection
or
Modem Modem
or
RF Modem
Measurement
78.6
78.6
Scale
Measurement
78.6
78.6
Scale
17