Ack to, Peration, Demux – B&B Electronics 232BSS4 - Manual User Manual
Page 21: Back to back operation (mux/demux), 232 bss 4, Scale measurement modem printer printer pc pc, Scale, E le ct ro n ic s

Documentation Number 232BSS4-0812m
17
&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
Back to Back Operation (mux/demux)
Scale
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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. 
