Step 7 symbol editting

Hi
If I need to edit a symbol or an entry in a DB (spelling mistake, for instance), do I need to open each program block using this symbol?

If I have "address priority" set to absolute address, Step 7 correctly updates the symbol when I open a block, but sometime later I may have switched to symbol has priority and if I open a block that I didn't open with address priority, it can't update.

Love those red italics.

Thanks

If I need to edit a symbol or an entry in a DB (spelling mistake, for instance), do I need to open each program block using this symbol?

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It depends. If the variable that you are changing is part of a UDT, then you only need to change it in the UDT (that is why ALL of my DBs are composed of UDTs). Otherwise you have to edit it manually.

If I have "address priority" set to absolute address, Step 7 correctly updates the symbol when I open a block, but sometime later I may have switched to symbol has priority and if I open a block that I didn't open with address priority, it can't update.

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This part confuses me. Why do you switch back and forth? Normally, you design a project with one of the two methods in mind, and leave it there for the duration. I'm not sure what would happen if I switched part way through the development, and I don't think I'll try and find out. Anyway, try this: Select Blocks>Check Block Consistency>Compile All, and see what it does (archive the project first until you get the hang of it). It may fix all of the problems automatically, or it will at least point you to the things it couldn't fix.

When I change a symbol name (i.e. correct spelling) in a DB or UDT, I'll switch switch the Address Priority to Absolute Address and then run the Check Block Consistency>Complile All. This will change the symbol in the DBs, FCs, and FBs. I then switch Address Priority back to Symbol. I don't have to open each block and update it. I think this is what paraffin power is after.

The Check Block Consistency works well with Step 7 version 5.3 but it was painfully slow with version 5.2. Even with version 5.3 and a large program, I have time to straighten up some of those unsightly paper piles on my desk.

S7Guy, I failed to get this to work if I leave the Address Priority to Symbol and then run the Check Block Consistency after changing a symbol in a UDT. The DBs will update, but not the FCs or FBs. Am I missing a step (besides spelling correctly the first time)? I don't want to manually open each FC and FB to correct symbol name changes.

By the way, I notice neither method updates the VATs. Is there a way to get the VATs to update too?

By the way, I notice neither method updates the VATs. Is there a way to get the VATs to update too?

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Not that I know of. The VATs don't seem to follow the Symbol Priority even though you can enter the variables symbolically. Therefore I sort of gave up on VATs a long time ago. I'll use them day to day for debugging, but I find it more valuable to arrage my data in the DBs very logically and then monitor them online.

The Check Block Consistency works well with Step 7 version 5.3 but it was painfully slow with version 5.2. Even with version 5.3 and a large program, I have time to straighten up some of those unsightly paper piles on my desk.

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I haven't used V5.3 yet, so I don't have anything to compare it to. But yes, it can be slow. Usually I schedule my compiles during breakfast or lunch so it can plod away on its own....

When I change a symbol name (i.e. correct spelling) in a DB or UDT, I'll switch switch the Address Priority to Absolute Address and then run the Check Block Consistency>Complile All. This will change the symbol in the DBs, FCs, and FBs. I then switch Address Priority back to Symbol. I don't have to open each block and update it. I think this is what paraffin power is after.

Click to expand...

Ok, I see what you mean now. Still, it sounds scary. I'm afraid that it would somehow screw up some addressing somewhere and it wouldn't be evident until my code blew up (I've seen this behavior in earlier versions, especially if I inserted a new bool inside an existing struct of bools.) But if you're confortable with this procedure, go for it.

One thing you might experiment with is the type of Symbolic Priority. If you look at the selections, you'll see that one option is "For All Accesses (I,Q,M,T,C and DB). I've never tried this, but maybe that option handles misspelling a little better.