CPU313C-2DP to UnidriveSP non-cyclic

I am using a Siemens CPU313C-2DP to communicate to a network of Control Techniques UnidriveSP drives by way of a SM-Profibus module (new installation -- all the latest firmware).

The network works fine. I have communication setup up with 8 cyclic in and 8 cyclic out.

I am having difficulty in figuring out how to utilize the DP-V1 non-cyclic parameter access. I am a bit confused as to how that needs to be setup (if at all) in the network config.

The manual talks about using the Profidrive channel and using the services to access the drive menu area, but it isn't clear to me what memory I access on the S7 end to accomplish this.

Any guidance would be much appreciated.

Have you called the CT guys in Grand Island NY? They are excellent.

BTalbot said:

Have you called the CT guys in Grand Island NY? They are excellent.

Click to expand...

Yeah, I've been emailing with JJ. They don't seem to have anything regarding non-cyclic comms using DP-V1. He says it has been quite some years since he last played with it. Most of what he was able to help me with was stuff I already had covered.

Thanks

Typically theres a couple of ways to do it
Setup the drive telegram using PKW data or using SFC58/58 which are
Read/Write data records

Maybe this will point you to a direction
What does CT support?

JRW said:

Typically theres a couple of ways to do it
Setup the drive telegram using PKW data or using SFC58/58 which are
Read/Write data records

Maybe this will point you to a direction
What does CT support?

Click to expand...

JRW, thanks for tip. I am looking through the PKW stuff now. Looks like I have a lot of reading to do.

CT supports DP-V1 asyclic data exchange, but they don't really have much information or any kind of examples showing how that is accomplished.

Damian
I have used the older CT profibus communication methods to talk to UnidriveV3

It is the same as CT Mode 1 - Non cyclic communications over Cyclic

I have a JSR for this in AB PLC5

It uses additional space on the cyclic comms then multiplexes telegrams in that space to read and write from any parameter
So a non cyclic read over Cyclic needs 8 cyclic messages to occur
If that time frame is acceptable then I have more information

The Manual goes into the detail but as usual is confusing on the first read

Hi Michael, I was avoiding using the "Acyclic over Cyclic" method simply because it added the same amount of words to me telegram that I would have needed just to make all my data cyclic. So it wasn't really gaining me anything but just making it more complicated. It is pretty clear to me how to get the "Acyclic over cyclic" to work. It is the DP-V1 Acyclic that CT doesn't seem to have a lot on info on. From what I have read so far it appears to require quite a bit of code to implement.

I understand what you mean - you are now beyond my knowledge

Was talking to a mate at the drive center in AU - He mentioned another method
Use a Sypt program to do your own multiplexing
eg Add one more word use 14 bits for the value (+/- 8192) and the other 2 bits to tell you which value it is (up to 4)

Or use unused bits in the status word to tell you the multiplex value (read into sypt, mask the unused bits, set the spare bits as you want then write to a spare register and have the profibus use that as the status word)