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what is the difference between compile and compare block?
Created by: hazem at: 6/13/2010 10:30 PM (3 Replies)
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| 6/14/2010 5:50 AM | |
Joined: 7/2/2008 Last visit: 8/26/2024 Posts: 928 Rating:
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Hello hazem,
1-Compile I believe he compile function you mean is found beneath check block consistency. This compiler checks your offline program structure and catches time stamps and calling errors. Like calling an FB that had been deleted or calling FB with wrong I/O interface. That's different to STL compiler that can catch both consistency errors and syntax errors as well in a source file. 2-Compare blocks This is used to compare either 2 offline programs or online program with offline one. So, you can use it when you doubt that a program in PLC is different to what you have on your engineering station and it will give you a report about differences between the 2 programs. And it can also be used with 2 offline programs to track software changes in programming phase. (F1 press in SIMATIC manager will give you more info. on both functions.)
The compiler report will never tell you if online program is different to offline program. And if you could compile both programs, they might be compiled successfully. What's strange here is that you downloaded the modified program and got the same message. I'll go far with my guess, Maybeyou had an EPROM and downloaded to CPU's working memory and forgot to load your program on EPROM. So, after a restart the program in EPROM was loaded again.
Most probably you had something wrong in your first download.
Because showing differences is the main job of compare blocks not the compiler's job. Best regards. H-H |
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