Rockwell Automation 1785-BCM_BEM, D17856.5.4 PLC-5 Backup Communication Module User Manual - Manual (Page 98)

Chapter
7
7-1
Programming Techniques
Read this chapter to familiarize yourself with techniques used to program your
PLC-5 backup system.
In this chapter we describe:
how to get started with a program to transfer data table values
two methods you can use to program the PLC-5 backup system to transfer
data table values
the behavior of specific instructions when used in your application program,
and give you suggestions for dealing with these instructions.
The 1785-BCM modules control switchover and transfer remote I/O data
without additional programming. However, if you want to transfer data table
values from the primary to the secondary processor, you must provide a ladder
program. Figure 7.1 shows the minimum ladder programming you must
provide to transfer 62 words of the data table between the two 1785-BCM
modules, and to provide 1785-BCM module status. You need to put this
program in both processors.
Chapter Objectives
Getting Started