12/20/2009 11:58 PM | |
Joined: 1/4/2008 Last visit: 9/2/2024 Posts: 703 Rating: (96) |
Hello, it's a long talk Better is to read something about, for example here and if it will interest you (I think so) here is the manual with other information. Regards Sydney |
12/26/2009 11:46 AM | |
Joined: 1/29/2006 Last visit: 9/11/2024 Posts: 446 Rating: (64) |
Hey, nbk! If you follow links, propsed by Sydney, you will see the very good explanation of differences between SCL and other languagaes..... . I personally allways use SCL, if I have to deal with arrays and pointers to arrays. I know, that there are perfectly good sollutions for this algorhythms in STL, and also some special sollutions for dealing with pointers in LAD, but i prefer working with higher language in this special cases. Why is that so? I really dont know.... . It might be, that I am too lazy to write programs in "assembler like" language, as STL.... There is also a "programmers background" issue and a lot of otherthings about which language is the best for use. I believe, there was a discussion held about that in this forum, a few months ago..... (Ups, it was a few years ago.....): /tf/WW/en/Posts/2872 Have fun! uel123 |
Last edited by: uel123 at: 12/26/2009 11:54 AM |
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12/27/2009 11:54 AM | |
Joined: 10/7/2005 Last visit: 9/18/2024 Posts: 3020 Rating: (1054)
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Hello nbk allow me to start by quoting Aret from THIS thread who's comparison of LAD/FBD, STL & SCLis- in my humble opinion - hard to beat as far aselegance and accuray of analogy is concerned:
As for your questions, here's my take:
SCL probably isn't commonly used. To start with itis not part of the standard Step7 (which offers you LAD/FBD and STL. To be abel to use SCL you will either have tobuy Step 7 professional or the standalone optional SCL package). Assuming you do have it, you will now have a High Level (Pascal like) language availablewhich in general makes the following programming tasks "easier": - Mathematical computations(e.g. you program/type in a formula in one line) - Loop programming (e.g. FOR, WHILE and/or REPEAT loops) - Indirect (indexed) addressing (this happens symbolically in SCL whereas you need to know/be aware ofaddresses if you do it in STL) Having said the above, once you finished your SCL code and hit compile, it will compile to STL code, so anything you can do in SCL you can also do in STL (and more memory and runtime efficient for that matter as you do remove theSCL to STL compiler created "overhead" code). At the end of the day, SCL is simply one out of seven available "languages" in Step 7 (STL, LAD, FBD, SCL, S7 Graph, S7 HiGraph and CFC are all on "offer" andif you use PCS7 you'll get the "real" SFC instead of S7 Graph)). SCLcan come in handy to use and canmake programming of certain taks easier or more convinient. You can however do everyting that is possible to do in an S7 in STL, so there is no case where SCL is a "must have". Last but not least, you'll find a wealth of SCL programmed blocks in the oscat Step 7 block library, which is available free of charge at www.oscat.de I hope this helps |
Cheers |
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