Cheddy

Thanks for the help.  The online version (CPU) is considerably different than the offline project.  Doing a compare it appears that several of the DB's are not the same.  I'll let you know how this goes.  Thanks again for the help.

Thanks for the reply. It's been about 10 years since I've even looked at STEP 7.  But that's kind of the issue I see, looking at the call from FB409 to FB373 I don't see a DB referenced at all in the body of the STL for that call to FB373.  FB409 has a DB but going into that DB it doesn't have any reference to I_Start at all.  I know the sequence works, it was running until they had an equipment failure and now they haven't been able to recover.  I can send some additional screen shots if you think this would help.  Thanks again!!

Hello, I'm pretty rusty on my STEP 7 software so looking for some help.  We have  FB's all written in STL.  In the block interface/environment there are IN, OUT, IN-OUT, STAT & TEMP sections that have tags assigned.  I have several boolean tags in the IN like I_Start, I_Stop and so forth that are only used in 2 or 3 areas of the STL but I cannot find what sets the I_Start tag. It isn't set in the body of the STL so must be from another FB or more likely a DB but can't figure where/how.  I suspect these are buttons on an HMI but none of the HMI's appear to have buttons that set these bits (Operators pressed any start button they could find).   This FB is called by other blocks but those blocks do not set these tags either.  I looked in the DB that flashed under the DB1 & DB2 header and there are tags with the same name but not the same address that shows in the interface of the FB.  Any help would be greatly appreciated.