VIPA PLC & MPI Protocol? Please help...

[JesperMP]

Hi Arik.

I use a CP5511 or ethernet myself. So I dont know about the Proces-Informatik devices.
However, if the Proces-Informatik devices were bad it would have been rumored in the market.

Anyway, for programming I would chose a USB and not a serial device, regardles of if it is from Siemens or Proces-Informatik or some others. The serial adapters are way too slow.

 

[J.A.du Toit]

Hi Guys,

Thanks a million for all your replies, I was away on Holiday the past week. That's the reason why I didn't post any comments.

I must say a great thanks to Mr. Dan Yost for your efforts, and Jesper for your help as well.

The idea behind this exercise was that, if the protocol needed a bit of "hammering", a PIC-Microchip (much cheaper) could be programmed to act as a translator/blacksmith.

So I'll talk to VIPA again...

And then I'll also try to get hold of Mr. Thomas Hergenhahn.

But in the mean-time, I didn't fully understand the difference between the two types of cables? What is the physical differences, or is it only software differences?

Do I understand it correct?
PG=Used to Program S7-PLC's?
OP=Used to Read DB's, Timers, Memory-Bits, etc... (No Programming)?

In the packets I posted: I tried to Read [DBB 777.0] to [DBB 777.19] or 20 consecutive bytes starting from [DBB 777.0]. And I suppose an OP cable should work well? Or am I mistaken?

 

[JesperMP]

But in the mean-time, I didn't fully understand the difference between the two types of cables? What is the physical differences, or is it only software differences?

The difference must be in the protocol.
My guess is that it is the connection types that are different.
STEP7 = PG connection.
HMI = OP connection.

 

[zottel]

Hi Guys,

Thanks a million for all your replies, I was away on Holiday the past week. That's the reason why I didn't post any comments.

The idea behind this exercise was that, if the protocol needed a bit of "hammering", a PIC-Microchip (much cheaper) could be programmed to act as a translator/blacksmith.

In principle, you could try this but...
1. The MPI bus is sort of Profibus.
2. Siemens and other vendors MPI adapters can connect to Profibus also.
3. When you connect an MPI Adapter to MPI/Profibus it does nothing
4. It gets commends from the RS232 side
5. The first commands tell the Adapter to participate in MPI/Profibus Token Ring Network
6. From the moment the adapter is in this network, it continues to communicate actively on the MPI/Profibus side to do at least the token passing.
7. The adapter gets some message from the RS232 side
8. It puts this message on MPI/Profibus when it is it's turn to speak.
9. It gets an answer from another MPI/Profibus participant (usually the PLC) and gives it back on RS232 side

10. If you want to do this with a microcontroller, you must implement a lot of the Profibus specifications. Profibus timing constraints are not easy to meet and Profibus speed goes up to 12MBaud. All adapters I know of use Profibus ASICs (special chips) for Profibus communication. While it might be quite possible to implement 187.5 kBaud Profibus communication with an average uC, you never know whether it is 100% Profibus compliant. So it may make a good programming adapter, but become very dangerous if somebody connects it to Profibus and real machinery is involved.

11. The data on RS232 side of MPI adapters is encapsulated by 3964R (older) or another (newer) transport protocol.

12 As far as I know, this same RS232 communication goes over VIPA's "green cable" and so do look the byte sequences you posted here.

 

[RheinhardtP]

Model of Vipa

THe protocol is different can be the only thing you would have to compare the two. It would be easier using a CP card if you are going to do the communication. what series VIPA plc is it??

The MPI adaptor had the electronics to alter the protocol, the cable cant change anything and is a hardware handshake.

Rheinhardt

 

[J.A.du Toit]

Hi Guys,

Thanks for still responding on my request for help...

But I did manage to get a very Basic 'Green-Cable-Protocol' from VIPA, which was just enought to implement a 'driver' in the Red-Lion Panel. (Which is working 100% by the way

So I'm not going the uC route anymore... (it was just one of the many attempts to solve the problem...)

Thanks again for all you support.

 

[mohamed yassen]

connect between vipa 315 2ag12 and laptop

how i can connect between vipa 315 2ag12 and laptop, what is the software to make connect , can i used step7 5.5 to make connect?

 

[osmanmom]

how i can connect between vipa 315 2ag12 and laptop, what is the software to make connect , can i used step7 5.5 to make connect?

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