Step 7 Symbols and DBs

I have program which was freshly uploaded from a Siemens PLC. No original copy, no symbols, no comments, joy joy. I'm going through and starting to label all the addresses, but have noticed that I cannot assign symbols to bits/words within a DB.

For example,
I right-click on "DB52.DBX262.3" and choose Edit Symbols and it takes me to the Symbol editor for DB52.

Can I give symbols to bits/words within the DB? And if I can, where I can access them? I tried from the Symbol list but it won't let me insert the DB52.DBX262.3 address without telling me it's invalid. I see in the DB editor I can assign comments, but no symbols.

It is more than likely an Instance Datablock, to change - edit the declaration of the paired Function block.

Have a look at your block view type column for the DB in question it will say something like 'instance data block for FBxx'

For multiple instance you will only need to do this once.

It's not an instance DB, just a DB. I attached a few pictures of what I'm seeing.

It looks to me like Symbols can't be assigned to bits/words. Kinda disappointing, but I guess I can work around it.

Tharon said:

It's not an instance DB, just a DB. I attached a few pictures of what I'm seeing.

It looks to me like Symbols can't be assigned to bits/words. Kinda disappointing, but I guess I can work around it.

Click to expand...

They are UDT's

I see now. I'll have to modify the Name field. Probably can't assign Symbols to UDTs.

Tharon said:

I see now. I'll have to modify the Name field. Probably can't assign Symbols to UDTs.

Click to expand...

You could try to re-create the UDT's.