S7 STL -- programming FBs

I'm attempting to write a function block that will use a pointer as an input that points to the DB where the results will be stored. I find I'm missing some basic info about handling pointers. I also don't see how to reference the instance data block. Can anyone point me to the correct Siemens manual that contains this info? So far I've found two manuals with the instruction list and timing information, but nothing else.

Use search in here.

TurpoUrpo said:

Use search in here.

Click to expand...

Did that before I posted. Read a lot of good stuff in the bubble sort thread, but never did find the answers I'm looking for.

I'd also like to find the Siemens manual that explains this stuff.

Can you be a little more helpful? <smile>

Well, have you ever looked at siemens manual? They explain a lot, but not how to make an application with stuff.... Yes we can be more helpful. Just wait a litte.

Where do you take data from and what do you want to do with it before storing to another datablock?

http://www.scribd.com/doc/47367113/Sitrain-S7-Pointers

Example attached.

Thanks! I was 'or'ing in a 0x84000000 to the DB address. I see you're just truncating it with a 0x00FFFFF. I also missed the L DINO instruction.

Can you point me to the Siemen's documentation about this stuff? Apparently I have also missed finding that.

I got my information from Hans Berger's book (STL) + experimentation:

http://www.amazon.co.uk/s/?ie=UTF8&...x=aps&hvadid=5860588329&ref=pd_sl_howzmu1eh_b

IMHO, you get lot more from just searching LD's posts (yes, I do have bergers book).

mbay, I have felt your pain.

You shouldn't need to buy another book. The Siemens documentation should be complete. The fact that questions similar to yours get asked over and over and over again should tell you that you aren't the only one that has had this problem.

I would pass just the DB number to a function and open the DB using the DI register within the function. Just to be safe I would save away the DI registers before changing it and restore the DI register back to its original value before exiting the function. The last time I tried this all the offsets from AR2 had to be hard coded. That was not good.