Chapter 1: Introduction - B&B Electronics 232MSS2 User Manual

Chapter 1: INTRODUCTION

The RS-232 Four Port Mini Smart Switch/Port Combiner, Model
232MSS2, allows one RS-232 host device to connect to as many as
four RS-232 devices. The switch can be controlled in two different
ways. The first way is referred to as smart switch mode. In this
mode, the switch is controlled by sending a programmable preamble
code to the "Master" port of the 232MSS2. The other way the switch
can be controlled is referred to as port combiner mode. In port
combiner mode, a slave port can gain access to the master port by
asserting a handshake line. If none of the slave ports have their
handshake line asserted, the switch can be controlled using the
preamble code.
The master port can be configured as a DTE or DCE port by an
internal switch setting. If the master port is configured as a DTE port,
the four slave ports will become DCE ports. The 232MSS2 supports
the following signals: TD, RD, RTS, and CTS.
The 232MSS2 has an enhanced mode which offers special
timer features. The timer features can be used to prevent slave
devices from receiving preamble commands, inadvertently switching
from binary/graphic file transfers, and inactive slave devices from
holding control of the master port.
The 232MSS2 will work with baud rates from 1200 to 115,200
bps; 7 or 8 data bits; even, odd or no parity; and 1 or 2 stop bits
(7,N,1 is not allowed).
NOTE: The data format and rates mentioned are used to switch
the 232MSS2. The communication between the devices can use
any format or data rate.
There are four LED's on the 232MSS2 to indicate which port is
connected to the master port. The master port has a DB-25S female
connector and the slave ports have DB-9S female connectors. The
232MSS2 requires 12Vdc at 10ma. which is provided through a
2.5mm power jack.
Documentation Number 232MSS2-0108 Manual
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445
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