Documentation Number 232D4SS84502 Manual
1
B&B Electronics Mfg Co – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104
B&B Electronics Ltd – Westlink Comm. Pk – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445
Chapter 1: HARDWARE
Introduction
The RS-232 Eight Port Smart Switch (232D4SS8) 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
232D4SS8, depending on the pins you use. Other options and
additional RS-422/485 ports are available by contacting B&B
technical support. 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 232D4SS8 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 232D4SS8 is transparent to data flow.
There are nine red indicator LED's on the front of the
232D4SS8. Eight LED's represent ports "A" through "H" and
indicate the selected port. The ninth LED is the power on indicator.
Nine connectors are located on the back of the 232D4SS8, 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 Smart Switch. This control
string consists of a user-defined character, address character, and
port character. When the 232D4SS8 receives the control string the
"Master" port will be connected to the designated port. There is no
delay through the 232D4SS8 and the data is not buffered. When
the 232D4SS8 is set to Smart Switch Mode Port "A" will be selected
at power up.
The eight ports on the 232D4SS8 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 232D4SS8.
