Removing Comm Link from a DmD File

[Bolt]

Is there a way to remove the "Comm Link in use flag" from a .dmd file?

So my underlying issue is:
I'm connected to a PLC with a Trend View open.  I make some changes to the project, write to PLC, looks good, continue to monitor in Trend View.

I want to write the exact same project to a second PLC.  I hit Save, then Save As, saving the currently connected project to a new name (can't have 2 projects open with the same name)

I open another instance of DmD, open the originally saved project, and then it gives me the "Comm Link is already in use..." message, click No.  Connect to PLC, Write to PLC, open a saved Trend View, done.

Now I go back to the original window of DmD, and it has a blue/red line in the Trend View and is no longer logging data ever since the second instance briefly tried to access the Comm Link.  So, so much for going through all the trouble to keep this window open.  Could have just disconnected, and re-connected to second PLC.

I should have known, as the same thing occurs if I'm connected to a PLC, and open asecond window to evaluate how something was done in a prior version.  If that project happened to have been saved last while the PLC was connected, it will "kill" the Trend View in the latest project I am working on.  So, if there was a way to strip the comm link status from a file before opening, saving/etc, that would "fix" my issue.

[franji1]

After doing the Save As, do a PLC->Disconnect then PLC->Connect (to the 2nd PLC).

[Bolt]

After doing the Save As, do a PLC->Disconnect then PLC->Connect (to the 2nd PLC).

But then I would be unable to keep the Trend View alive on the first PLC?

[franji1]

After doing the Save As, do a PLC->Disconnect then PLC->Connect (to the 2nd PLC).

But then I would be unable to keep the Trend View alive on the first PLC?

Just make a copy of the .dmd file with the original session open using Windows Explorer.  Launch a 2nd instance of Designer and open up that copy.  It will tell you that the link is in-use, which is OK.  After the disk project opens, just do PLC->Connect on that copy to the 2nd PLC, write it to the 2nd PLC, and then Save it to disk.

You will have 2 online sessions, one with a Trend view with the first PLC, and a 2nd identical program, but in a different project file and different PLC.

[Bolt]

...It will tell you that the link is in-use, which is OK....
You will have 2 online sessions, one with a Trend view with the first PLC, and a 2nd identical program, but in a different project file and different PLC.

There in lies the problem, when the "Comm Link already in use.." message pops up, it "breaks" the comm link with the Trend View in the first project, and I can't get it to come "alive" again.

[franji1]

There in lies the problem, when the "Comm Link already in use.." message pops up, it "breaks" the comm link with the Trend View in the first project, and I can't get it to come "alive" again.

Aha!  We'll look at it.

[Bolt]

Have you been able to find any work arounds here? It's really frustrating me with the work I'm doing today.

[franji1]

Have you been able to find any work arounds here? It's really frustrating me with the work I'm doing today.

Sorry, no.  I hope the fix is trivial, but until I look at it, I won't know.

[franji1]

I figured out how to get the Trend View re-started:

1. On the "original" Designer doing Trend, do PLC->Link Info to bring up the Link Info dialog
2. Uncheck the Link Enabled checkbox
3. Wait a second
4. Check the Link Enabled checkbox
5. Trend View should start plotting data again

There is an issue when the 2nd Designer session tries to re-use the Comm Link in the copy of the project of the 1st Designer session.  Trend View receives a notification that the Link is Disabled, which the Trend View SAVES THAT STATE (Trend View does not update element status while the link is Disabled).  But the "Enable" link notification is never received - so the Trend View status "hangs".  If you manually do the steps above, those actions should "reset" the Trend View state and get it going again.

[Bolt]

Had a chance to use the method, works well enough for me. Thanks!