DP Communication

Hi,
I have 3 S7-313C CPUs each of them attached with a CP324-5 Communication processor for DP communication with a S7-400 (I dont know the exact CPU code) as a master. I want to receive and send data to these slaves from S7-400. I have found some documentation from www.sea.siemens.com/Support but I could not really get the idea from those documents. I am curious about which FC or FB to use because there are some FCs and FBs for DP communication and I dont exactly know which one would fit for my project. Also on the S7-400 side how the data for each S7-300 slaves could be adressed. If you have a sample piece of code ,not the whole project, only data transmission part on slaves and the master I would greatly appreciate your help.
Thanks in advance.

Hakan ARMUTCU
SC Endüstriyel A.Ş.
Gersan Sanayi Sitesi, 657.Sk.,No:70
Batıkent/ANKARA
Türkiye

Hello aldarin;

This link take you to a Siemens FAQ discussing the setting of a CP342-5 as a Profibus slave, connected to a S7-300/400 master. There is also a downloadable sample project covering the subject:
http://support.automation.siemens.com/WW/view/en/6519580

As noted in the above link, a CP342-5 setup as a DP slave will need FC1 and FC2 to exchange between your CPU (the CPU313C) and the communication processor over the backplane; echanges with the master should be transparent,

This link provides information on different communication blocks you can use for different types of exchanges between DP partners, including FC1 and FC2:
http://support.automation.siemens.com/WW/view/en/19054790

Hope this helps getting you started,
Daniel Chartier

thanks. I will take a look at it now.

Do not forget to configure the hardware for profibus communications first. Connect the cpu's to a profibus network. Connect to the master CPU the preconfigured s7-342-5 stations (hardware catalog, profibus dp) and configure the I/O to exchange data. The functions as described needs to be called cyclic and configured with exactly the same amount of bytes otherwise you will get a system failure.
If you need the profibus port of the cpu you have to use sfc's to communicate.