232XSSD43800 Manual
1
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5104
Chapter 1: HARDWARE
Introduction
The RS-232 Eight Port Expandable Smart Switch (232XSSD4)
allows one RS-232 host device to connect to eight asynchronous
serial devices. Refer to Figure 1. Four RS-232 ports and four RS-
232 or RS-485 (two or four wire, send data contol) are standard on
the 232XSSD4, depending on the pins you use. Other options and
additional RS-422/485 ports are available by contacting B&B
technical support. The 232XSSD4 can be easily expanded to add
up to sixty additional ports for a total of sixty-eight ports by using the
Model 232PE Port Expander. Ports configured as RS-232 support
signals TD, RD, RTS, CTS, DTR, and DSR or CD. Refer to Figure
5. Ports configured as RS-422/485 support signals TD and RD only.
Refer to Figure 6.
The Master port is DTE or DCE configurable. RS-232 ports "A"
through "H" are configured as DTE ports. The 232XSSD4 will switch
with baud rates from 300 to 38,400 bps, 7 or 8 data bits, even, odd
or no parity, and 1 or 2 stop bits. After the switch is made the
232XSSD4 is transparent to data flow.
There are nine red indicator LED's on the front of the
232XSSD4. Eight LED's represent ports "A" through "H" and
indicate the selected port. The ninth LED is the power on indicator.
Ten connectors are located on the back of the 232XSSD4, a twenty
pin expansion bus connector, a DB-25S female Master port
connector, and eight DB-25P male connectors for ports "A" through
"H". Refer to “Front View” diagram.
Port selection is accomplished by sending a programmable
control string to the "Master" port of the Expandable Smart Switch.
This control string consists of a user-defined character, address
character, and port character. When the 232XSSD4 receive the
control string the "Master" port will be connected to the designated
port. There is no delay through the 232XSSD4 and the data is not
buffered. When the 232XSSD4 is set to Smart Switch Mode Port "A"
will be selected at power up.
The eight ports on the 232XSSD4 can also be used as a smart
switch/port combiner. In addition to using the Master Port for port
selection, any of the eight ports can select the Master Port by
asserting their CTS line. This function is enabled by setting a switch
inside the 232XSSD4.
