Specifications

C - 12 RSLinx – Training Guide
BreakPoints
Breakpoints are special conditions that you assign to a rung or rungs. When these special
conditions are met, scanning (execution) of your ladder logic will be frozen at that given
rung/ breakpoint and the program scan will be turned to
One Rung Mode. This way you
can examine the data table, which is also now also frozen at that given point.
There are two circumstances where you may wish to assign breakpoints. Either you assign
a breakpoint to an existing rung whose True/False continuity needs to be evaluated or you
create a special rung(s) with conditions you want to capture.
For example, you might want to test for several inputs which should never go on at the
same time. Or perhaps you might want to test for some data table condition where x = 2
and y = 3 (one or several data table addresses equal some particular value(s) that you want
to know about).
You program the rungs in normal ladder logic (RSLogix or A.I. Series), but set the
breakpoint conditions in the emulator itself. When the rung which has been assigned a
breakpoint “hits” the breakpoint conditions, ladder logic scanning stops at that rung, and
the emulator is in put into
One Rung Mode.
The possible conditions for breakpoints are: True/False, or Any, and these interact with a
counter so you can also include the number of times the rung has gone true, false or any
(any simply means the rung has been scanned).
In the above example, there are four breakpoints, but the last one is inactive (and thus
wouldn’t have any effect). This might show a situation where, say, a special program file 6
was setup only to contain breakpoints, and in it are three special rungs which are designed
to “trap” conditions. For example, the first breakpoint would “hit” if rung zero in program
file six goes true once. The second breakpoint would hit if rung one in program file six
goes false five times. The third breakpoint would “hit” if rung zero in program file 3 were