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Geo1000

Function Block addressing

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Hello all. 

I have a program which has 8 function blocks.

I recently added extra functionality to one of the programs (not the function blocks).

I added the new variables to the global symbols table and added the new code, but when I compiled the new code, the variable addresses in three of the function blocks had changed. This is a problem, because we use memory cassettes to download new versions of code, so when the new version is downloaded to a machine in some far flung part of the world, these variables will be overwritten (they are hours run variable, so are important for servicing purposes).

 

My understanding is that CX assign's variable addresses in Function Blocks and we have no control over this. Bit if I only added variables to the Global symbol table, why are the FB addresses affected??

 

Any input appreciated. 

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