Sharing S7 projects. What must I do?

[BobB]

I am glad that someone else thinks Siemens software is a heap of ****!! The most painful software I have ever used and has not improved since I used it 10 years ago quite frankly!

Perhaps I have been spoiled with good software.

 

[Pandiani]

Peter, I use PLCSIM to test. I can test. I see that you changed FB2. Have you simulated my version of FB2 that I sent you by email?
Did you find error there?
You didn't answer me regarding that n=1 that should have been noved to first scan section?

 

[Peter Nachtwey]

Peter, I use PLCSIM to test. I can test. I see that you changed FB2.

I changed it to be closer to the Scilab version and I added some comments. There were also sections of code that didn't need to execute each time. Moved some variables into the temporary section since they are computed as needed and don't need to persist from call to call.

I changed the first_scan to a run input. This is because we may want to change parameters without restarting the program. It isn't a big deal.

Did you find error there?

No, but I couldn't edit a ladder or STL program with the errors I mentioned above.

You didn't answer me regarding that n=1 that should have been noved to first scan section?

I thought I did. n must be initialized only once during the first scan or when the parameter are recalculated. After that it is used to index into the circular queue ( FIFO ) which I called DTQ for dead time queue. n must be incremented only one each time FB2 is called and should always be between 1..nDT. This is the key part that you didn't have right initially.

I am out of action today. We are having a rare snow storm so I am staying home rather than drive with all the other idiots that will run into me. I didn't bring my laptop home and my laptop can't start the virtual machine with the Step7 anyway.
Yesterday was very frustrating This should be easy. Gerry did this the easy way

 

[rdrast]

Just as an aside, I'm absolutely thrilled that Siemens PLC's are absolutely forbidden at the company I currently work for.

Aside from Step7 and it's multitude of pieces being a complete resource hog, the very idea that a simple PLC program somehow needs to have a huge directory structure and thousands of files on my hard drive made me insane.

 

[Peter Nachtwey]

I found this item on the Siemens support site.

https://support.automation.siemens....d&objid=10805390&DataKey=10805390&treeLang=en

By declaring a data block in the source code you can generate the DB each time the FB is compiled. That would have helped with my data block deletion and creation I think.

I added

// This generates a new DB2 each time FB2 is complied

DATA_BLOCK DB2 FB2 

BEGIN
END_DATA_BLOCK

to the bottom of the source to FB2.