Siemens CP143 with single processor using 4 interfaces


Thread Starter

Peter van den Berg

We want to improve the speed of our network connection with a Siemens 155U and a CP143 ethernet card.
We are trying to use 4 interface areas instead of 1. The 1st interface area seems Ok, but the other 3 do not communicate.
Is it possible to use 4 interface areas with a single processor in connection with a CP143? If yes, how can I accomplish that?

I am not an expert, but I will try to help here. I'm assuming you are going to go from 1 cp143 to 4 cp143's. Things you should check are:
1) That the slots in your chassis that you are using for the CP143's are slots that allow a CP.
2) That you address each card uniquely.
3) That you add the "jobs" to each card independently via com143.
4) That your send/receive/fetch jobs called from the user program call the proper ANR/SSNR numbers for the card address and job number on that card.
5) That the communication partners have the proper parameters to communicate with the specified CP. Ie..that the remote database has the correct MAC and TSAP's for the CP that the communications are to be made.

A great source on Siemens S5 on this board has been Donald Pittendrigh. If he's reading today, he may be able to get you further than I have!!

If I understand your question you want to use four interface areas in a single CP143.

I’ve done that in a CP1430 and didn’t get better performance. The advantage of using different areas or "pages" is that you can have different code pieces talking through the CP independently.

Any way an important point to establish communications in different pages is to "synchron" each one independently. This is usually done in OB21 or OB22 (or both).

Manuel Madrid

In order to increase communication speed you should check how often do you call the send and receive jobs for the cp143.

If you call these jobs from OB1 your performance will be affected by the PLC cycle time which is not constant. I recommend calling the send-all and receive-all jobs from time dependent blocks (OB12, OB13, etc.), in a 155U you can set this blocks to run every 20ms and they will process bus messages at this rate.

Good luck