Siemens to CLX on Profibus

[cdavis]

Has anyone ever setup communication between a Siemens S7300 to a ControlLogix PLC using a Prosoft MVI-PDPS slave module? The Siemens is the master and the Prosoft card is the slave.

I can see the Prosoft card on the profibus network, but when I try and read using SFC14 (DPRD_DAT), it gives me the following error:

"The length of the specified destination area is not identical to the user data length configured with STEP 7"

I have set up the prosoft card for 50 words of I/O. I have set up the module in Step7 with 50 words of i/O.

 

[LJBMatt]

Double check to make sure that you are dealing with words and not bytes. Most AB cards will default to 2 or 4 byte words, but Siemems being octal uses 1 byte words.
Also check for any overhead information that the Profibus slave card adds on top of your user I/O words.

 

[cdavis]

Data is being transferred between the ControlLogix and the Siemens. I can read the data if I access PI's individually. The DPRD_DAT instruction is the problem now. I continue to get the error that I described above. The slave is configured for 50 words (16-bit) and the DB that I am reading into contains 50 words.

 

[cdavis]

Working finally

Ok, I got back to working on this problem and got it figured out. When you drop a slave into the Siemens hardware config, pay close attention to the configuration of the modules. If the module says "consistent over unit" as opposed to "consistent over length", you will only be to read/write 4 bytes at a time (even using SFC14/15). I got a FC from Siemens called PI_Move and PQ_Move that you can use instead.