Hardware reference guide
Intelligent/Special Purpose
35013379 02 October 2007 407
Rear Panel 
Switches
The MSX has an RS-232 serial port to connect the module to an IBM PC (or 
compatible) running the Modicon Motion Development Software (MMDS). A two-
position Dip switch is located on the rear panel of the module (see the following 
illustration). SW1 is used to specify the module’s operating mode (984 or MMDS 
control). SW2 is used to specify the communication characteristics of the Modbus 
port upon power-up.
The following figure shows the two-position Dip switch. 
The following table shows the settings for the Dip switch settings.
Switch Setting Function
SW1 *Closed MMDS control
Open PLC control
SW2 Closed Programmed baud
*Open Modbus default
*Factory setting
Note: SW1 and SW2 are open when they are switched away from the internal PCB 
of the module.
CLOSED OPEN
1
SLIDE SWITCH
AREA OF DETAIL
2
This document provided by Barr-Thorp Electric Co., Inc. 800-473-9123 www.barr-thorp.com










