DL240 Editting Crash

[cnrservices]

Thanks Guys,

If I got this right - Stage S0 isn't shut off or called anywhere else in the program so it must always run every scan. Or not?

If I put the timer to check X11 in SO and then replace all XIC X11 with XIC my timer Done this should work?

marksji,

If some input or program code turned off S22 without me adding any calls to stages would this cause a CPU fault - and stop the PLC communicating with Directsoft, unable to check error, clear fault, change mode, etc.? (Remember - on 2 different CPU's, but the same edit worked fine in another stage.)

Again, thanks for all the input.

 

[Thomas Sullens]

stages

Greg you are right S0 is always scanned because it is ISG
so it is ACTIVE at powerup it is not Jumped out of or reset
any where in the program. This means GTS K1,K2,K3 are always
scanned. S100 is always on because it is SET in S0 and never
reset so GTS K4, K5 are always scanned. If you JMP out of a
stage the stage you JMP out of is turnedoff the next scan.
If you JMP out in the middle of a stage it
finishes all below it and turns off the next scan.
I hope this helps?
Tom

 

[testsubject]

I swear by stage programming and will take a look at this when i get into work today.

 

[MarkTTU]

If some input or program code turned off S22 without me adding any calls to stages would this cause a CPU fault - and stop the PLC communicating with Directsoft, unable to check error, clear fault, change mode, etc.? (Remember - on 2 different CPU's, but the same edit worked fine in another stage.)

Any stage turning off shouldn't cause a CPU fault. What firmware are you using and is it the latest for the 240?

Also, what I/O cards are in what places in the rack? I didn't have any I/O when I tried it and didn't get a fault, I might get different results with some I/O.

 

[testsubject]

Mark,

That was going to be my first question; what is the firmware. Could be a new software old firmware issue. Been there, done that.

cnrs,

What output controls the dropping of the carton? I also think that it is somewhere from s22 on where you might be having your problem. As far as the fault is concerned, my first guess would be that the timer is acting funny from within the subroutine and could have caused a timeout condition. I can understand some of the posters positions in having difficulty understanding this program. I try to never have more than one JMP to any Stage. I liken it to doublecoiling. It also makes it difficult to troubleshoot.

 

[cnrservices]

Thanks for all the help,

I added a rung to S0 to time delay X11, and changed all other checks to the timer. So far all tested OK.

Mark & testsubject:
I'm not sure of the firmware in the original 240 CPU I removed, but the NEW 240 I replaced it with was just bought from A-D last month - so it should be very current firmware.

P.S. - Just for fun I tried the original noted edit in line 90 & the CPU faulted, no COMMs, DirectSoft reported "Unable to verify write to memory" - had to power down PLC & restart to get COMMs, had to close DirectSoft AND DSLaunch and restart to activate 240 link.


Again, thanks for the guidance - now that this thing is done I can get back to programming REAL PLC's - #&^&$ them stages.

 

[elevmike]

cnrs,

you can update your old 240 cpu with new a new firmware chip for $7.00. I found out the hard way that some instructions dont work with earlier firmware.

 

[testsubject]

Greg,

I say the same thing about Rockwell software. I just do not know why you would want to have to use function keys to draw rungs and branches when using the arrow keys is just so much easier!

I rely very heavily on the scan time reduction that I get from using Block/Stage programming. It can be a bit confusing to the uninitiated, but when you get a handle on it, there is no other way I would rather use.

Bob

 

[cnrservices]

I just do not know why you would want to have to use function keys to draw rungs and branches

Funtion keys?

I dont think I have pressed any of the function keys on my keyboard more than 5 times in the last year.

Other than typing in descriptive names & timer settings, I program RSLogix using only a trackball & mouse - actually I don't even keep the keyboard in front of me when I am programming, I have to move stuff & bring it down when I need to type (like here.)

 

[Eric Nelson]

I rarely use a mouse when programming. Soooo much quicker with hotkeys, even for a two-finger typist like myself... :nodi:

beerchug

-Eric

P.S. That explains your lack of nicknames and comments...

 

[cnrservices]

That explains your lack of nicknames and comments...

Eric,

The reason the program didn't have nicknames & comments, was it was an upload from a machine in service I was working on without schematics or an original program.

A lot of customers (especially this particular cheap one) balk at paying $135.00 per hour for Panel Backtrace Engineering even before the troubleshooting begins.

 

[Eric Nelson]

The reason the program didn't have nicknames & comments, was it was an upload from a machine in service I was working on without schematics or an original program.

Yeah, I know. I was just kiddin'...

beerchug

-Eric

 

[testsubject]

Eric,

Same here. CTRL+(arrow) gets me all the rungs and branches that I want. I rarely use the mouse. Hotkeys are our friends! So are Block/Stages.

Bob

 

[Eric Nelson]

Never say I didn't warn you...

So are Block/Stages.

One of these days you're gonna have to program a different brand and ask "Where's my $%^&@#$ SG instruction?"... banghead

Nothing wrong with 'em, but I need portability. I accomplish essentially the same end result with my 'step progamming', and it works on ALL brands! (that I'VE ever used)... :nodi:

beerchug

-Eric

 

[testsubject]

I say that everytime I have to use RS. (Dumb software!)

lolis

Bob

P.S. I do have a serious question though. How do you minimize scan time in RS? Since I started using Block/Stages, my scan time for a 3000+step program went from 60+ms to High 20s. This was important to me. That is one of the main reasons I really love it.