Allen Bradley Ladder Logic Array Indexes Getting Jumbled Up

BKoch said:
I DONT CARE ABOUT DOWNLOADING



🤷 What I am saying is that when someone connects to this controller and does an upload, as you do when you are coming to a job site other people are working on, the upload messes up this routine!
Click to expand...

An upload will get whatever is in the controller, that is your decision.

A download will put the project from your PC into the controller, again that is your decision.

But what you did in your video, was a complete waste of time, you went offline to make a change, and then to go back online you did an upload, completely wiping out the offline change you made.
 
BKoch said:
I DONT CARE ABOUT DOWNLOADING



🤷 What I am saying is that when someone connects to this controller and does an upload, as you do when you are coming to a job site other people are working on, the upload messes up this routine!
Click to expand...

An upload cannot "mess up" anything, you are simply taking a COPY of what is in the controller into your PC. What you do with it after that is your choice.

And you absolutely SHOULD care about DOWNLOADING, because that is the only way, other than by doing Online Editing, that you are going to change the code in the controller.

Step back, sit down, and calmly READ what has been written, you so obviously have your Upload and Download philosophy incorrect for Allen-Bradley
 
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Taking a closer look at the video, there is a definite difference in what is showing in the online state, and what is shown after uploading, regardless of what went on while offline.



Yes, changing the element from 18 to 22 was a waste of time, but it should not have changed to 16 when connecting to it again.


EDIT: Apologies for the pixelation.
EDIT: Highlighted changed area.
EDIT fixed time stamp of first image.

2021-02-10_17-06-42.png
 
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JordanCClark said:
Taking a closer look at the video, there is a definite difference in what is showing in the online state, and what is shown after uploading, regardless of what went on while offline.

Yes, changing the element from 18 to 22 was a waste of time, but it should not have changed to 16 when connecting to it again.

EDIT: Apologies for the pixelation.
Click to expand...

You may have spotted something I did not, but I stand by all I have said regarding the Upload/Download scenario.

I have been programming Allen-Bradley PLCs since 1987, and have been training other people how to do it for the past 12 years.

I will review the video.
 
JordanCClark said:
Taking a closer look at the video, there is a definite difference in what is showing in the online state, and what is shown after uploading, regardless of what went on while offline.

Yes, changing the element from 18 to 22 was a waste of time, but it should not have changed to 16 when connecting to it again.


EDIT: Apologies for the pixelation.
EDIT: Highlighted changed area.
Click to expand...


Check your headings in your screenshots, they can't both have the same time = 3:37 ?
 
I had an issue not very long ago with firmware v32 where, after an online edit and a power cycle, would cause a CIP offset error on the HMI when reading the tags and I couldn't go online with it at all(technote here). Although there was no real root cause given, upgrading to v33 to fixed it.

I'm not saying this artifact is from a similar cause, but it does bear noting.


I'll fix the image momentarily, but the first one is at 0:07
 
Here is a more clear 1080p, shorter video that shows the upload error I've been experiencing


http://youtu.be/ZwQpdov56r8


Note that on rung 45, where all indices are supposed to be 42, two of them become 40 after the upload
 
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BKoch said:
Here is a more clear 1080p, shorter video that shows the upload error I've been experiencing


http://youtu.be/ZwQpdov56r8


Note that on rung 45, where all indices are supposed to be 42, two of them become 40 after the upload
Click to expand...

daba, you need to watch this video. He makes a change to rung 43 offline, then uploads. Obviously the offline change will be wiped out. The issue is, the array indexes on rung 45 are now different after the upload.

Edit: I wonder what you would see if you uploaded with no file? I'm wondering if the software is simply not displaying correctly, if what is actually in the controller is not really changed.

Edit2: If my first edit is true, your copy is now wrong, so if you were to download it, what is in the controller would then be wrong. This is similar to the issue I was remembering where when you saved a program, rungs would vanish from your ACD. It would appear that the rungs were gone if you looked at them in your online program, though they would actually exist in the controller. I'll see if I can find the technote.

Edit3: KB PN997 was the one I was thinking of...
 
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My main takeaway from this is that there is some bug in RSLogix where it has trouble uploading a routine with this many static indices.


The only thing I can really think to fix this is to try and remake the routine in structured text. My thinking is that there's no way it could mess it up if it's just uploading text. :confused:


Only problem is I'm not very proficient at ST, guess there's no better time to learn than the present :ROFLMAO:
 
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dmroeder said:
daba, you need to watch this video. He makes a change to rung 43 offline, then uploads. Obviously the offline change will be wiped out. The issue is, the array indexes on rung 45 are now different after the upload.

Edit: I wonder what you would see if you uploaded with no file? I'm wondering if the software is simply not displaying correctly, if what is actually in the controller is not really changed.

Edit2: If my first edit is true, your copy is now wrong, so if you were to download it, what is in the controller would then be wrong. This is similar to the issue I was remembering where when you saved a program, rungs would vanish from your ACD. It would appear that the rungs were gone if you looked at them in your online program, though they would actually exist in the controller. I'll see if I can find the technote.

Edit3: KB PN997 was the one I was thinking of...
Click to expand...

From your edit2 : I wonder what the outcome would be if, after uploading and seeing the "errors", you then saved, closed the software, re-opened it, and then had a look online again to see what was in the controller.

I am thinking this might just be a display issue, but if uploading is changing indices at other places, then it makes me very uneasy - what else could it be doing ??

@BKoch - I notice that all your indices match on each set of rungs, including the ONS, and the code appears to be identical. Could it be a candidate for an Add-On Instruction ?
 
daba said:
From your edit2 : I wonder what the outcome would be if, after uploading and seeing the "errors", you then saved, closed the software, re-opened it, and then had a look online again to see what was in the controller.

I am thinking this might just be a display issue, but if uploading is changing indices at other places, then it makes me very uneasy - what else could it be doing ??

@BKoch - I notice that all your indices match on each set of rungs, including the ONS, and the code appears to be identical. Could it be a candidate for an Add-On Instruction ?
Click to expand...


Yeah if I close out and go back online with the original file it is fine, so it is just a display thing. The problem then is if someone doesn't notice this and makes other changes then it solidifies the errors from the upload.


As for remaking the routine, you're right there are a lot of almost identical rungs, just with incrementing indices. I figure in my ST remake I can use a FOR loop to get this done in a lot shorter program
 
BKoch said:
Yeah if I close out and go back online with the original file it is fine, so it is just a display thing. The problem then is if someone doesn't notice this and makes other changes then it solidifies the errors from the upload.

As for remaking the routine, you're right there are a lot of almost identical rungs, just with incrementing indices. I figure in my ST remake I can use a FOR loop to get this done in a lot shorter program
Click to expand...

So about a week ago, one of my coworkers experienced the issue in the KB article that I mentioned. A whole routine worth of rungs vanished. He did not notice that the rungs were gone. Had to make an offline change and download, the copy with the missing rungs was downloaded, wiping them out in the controller.

I believe the rungs were actually in the PLC when he was online, this is just an LogixDesigner artifact. Of course, the consequences are realized later when someone downloads with that copy. This is likely a similar situation. Ouch.
 
Instead of saving, try save as and create new file perhaps? Maybe old files becoming corrupted somehow.

Check your backup files too, perhaps those may have the correct values and work properly compared to original file?
 

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