Rockwell Automation 1775-MX_S4A,D17756.3.1 User Manual PLC-3 BACKUP CONC(OR.DU1 User Manual

Page 75

Using the 1775ĆMX

Memory Communication Module

Chapter 4

4-28

Table 4.J

Enable Compare

If the memory communication module:

Then:

completes the program compare without

error

bit 13 is set in file 4, word 0 of the status section.

(You must reset this bit.) The memory

communication module continues the comparison

until a miscompare occurs.

encounters a miscompare LIST will show:

Enable Program Compare

Disable Program Compare

bit 12 is set in file 4, word 0 of the status section;

the address of the rung containing the

miscomparison is put into file 4, words 1 and 2;

and bit 14 is reset in file 4, word 0.

To continue the comparison, you must reset the

status bit (bit 12 in file 4 word 0) and reselect

ENABLE COMP

For a further description of status bits, see Using

Data Table Status Bits in chapter 5 of this manual.

For a program comparison to occur, the primary processor must be in run
mode or test mode. If you switch the primary processor to program mode,
the program comparison function becomes inactive. When you switch the
primary processor out of program mode, program comparison will become
active again.

To specify limits in the ladder program, use the syntax shown below. You
can use either the slash (/) or the comma (,) as a delimiter between
parameters.

ENABLE COMPARE

m/s/f

where:

is the limit for the main program section

is the limit for the subroutine program section

is the limit for the fault program section