CompactLogix ...First Pass bit ...where? Help!

[Joe Bob Briggs]

I'm programming a CompactLogix project (1769-L32E) and ...it's my first time with RSLogix 5000. I need to write some configuration info to a couple of module profiles just once ...when the logic executes the first scan for example. There doesn't seem to be an S:1/15 First Pass bit or tag or ??? I can easily use the Power Up config of the controller to run a Power Up routine, but the help file only mentions that this routine runs "after an abnormal power-down/power-up during RUN mode". Does it also run when somebody switches to "RUN"? How do I solve my "write module profile config data once on first scan ...normal start *OR* upon a power up after a power loss"??????

Thanks a mil!

JBB

 

[TConnolly]

S:FS

I believe that each task has a S:FS bit, something to keep in mind when you are designing your program, especailly with periodic tasks that may not run until the continuous task has executed several times.
See accessing runtime controller configuration and status under online help.

 

[Joe Bob Briggs]

Thanks you! You're a gentleman and a scholar!

Now ...why the heck doesn't the help system have anything under all the stuff that *I* looked under ("first pass", "first scan", etc)? Don't answer... haha.

JBB

 

[Gerry]

...don't panic when you never see the bit high-lighted - it never is.

(You might expect to see the following high-lighted during normal running, but you won't)

   S:FS

 --]/[--

 

 

[TConnolly]

That is because they are not booleans, at least not in the sense of normal program tags.. S:XX is is a shortcut method to system flags instead of having to make a GSV call.

 

[Joe Bob Briggs]

Thanks again! One good thing about running into difficulties or questions is that you usually end up learning 2X or 3X more than you started out to... thx.


JBB