Profibus Master Slave communication

[JesperMP]

But if he uses the S7-300 he will need the TIA Configuration software, and the avaluationversion works only for 20 days or so, correct? This is why I believe the simulator would be better for the master, and for the Profibus DP slave, yes, I totally agree, the best is to get a used device from eBay.

He would need STEP7 Classic (V5). If he purchase the very old (and cheap) CPU that I suggested, then it is not supported by TIA since TIA only supports the very latest S7-300 hardware.
If he dont have STEP7 already, then it is indeed an extra expense. Alternatively he could get the 30-day trial software.

My suggestion regarding the old S7 hardware is because for Profibus he will need some kind of hardware. And old S7 stuff is abundant and cheap. To my knowledge there is no such thing as a "Profibus stack" that you can install on a PC to work over a serial port for example.
When you mention "simulator for the master", do you mean there exist a software-based Profibus master for PCs ?

Anyway, I think that to learn about these protocols by simply listening in on the wires will be a big task, if not impossible. I wonder what it is that momo aims to achieve.

 

[momo1501]

With Codesys there is a Raspberry PI version You can get two RaspberryPi use one as the profinet Controller the other as the Profinet slave. Or you can use the Windows version of Codeys, in which the PLC application will run in Windows. You can have two PCs. and you can combine for example Windows for the controller, Raspberry for the slave. The Wireshark will decode in great detail the communication.

AlfredoQuintero: this is what I need to do. Would it be possible to give me more details about that? Should I have a raspberryPI card to do it? Or it would be possible through two PCs running windows (I think one PC is enough as I can use the localhost 127.0.0.1 address)

Thank you for your reply

 

[cardosocea]

AlfredoQuintero: this is what I need to do. Would it be possible to give me more details about that? Should I have a raspberryPI card to do it? Or it would be possible through two PCs running windows (I think one PC is enough as I can use the localhost 127.0.0.1 address)

Thank you for your reply

Are you looking for ProfiBUS or ProfiNET? These sound the same and although similar at some level, they are definitely not the same thing.

 

[momo1501]

Are you looking for ProfiBUS or ProfiNET? These sound the same and although similar at some level, they are definitely not the same thing.

I am aware that they are different. I am looking for master and slave softwares communicationg through virtual serial ports for both of them.

Best regards

 

[momo1501]

He would need STEP7 Classic (V5). If he purchase the very old (and cheap) CPU that I suggested, then it is not supported by TIA since TIA only supports the very latest S7-300 hardware.
If he dont have STEP7 already, then it is indeed an extra expense. Alternatively he could get the 30-day trial software.

My suggestion regarding the old S7 hardware is because for Profibus he will need some kind of hardware. And old S7 stuff is abundant and cheap. To my knowledge there is no such thing as a "Profibus stack" that you can install on a PC to work over a serial port for example.
When you mention "simulator for the master", do you mean there exist a software-based Profibus master for PCs ?

Anyway, I think that to learn about these protocols by simply listening in on the wires will be a big task, if not impossible. I wonder what it is that momo aims to achieve.

Dear JesperMP,
Thank you for your reply
"When you mention "simulator for the master", do you mean there exist a software-based Profibus master for PCs ?"
Of course, I downloaded such a software for a PC

What I need to do is very simple. I need to write a source code which can go and retreive data from real world profibus, profinet, hart and hart-ip devices. I need such softwares in order to do tests for the code I will develop

 

[JesperMP]

Dear JesperMP,
Thank you for your reply
"When you mention "simulator for the master", do you mean there exist a software-based Profibus master for PCs ?"
Of course, I downloaded such a software for a PC

I am curious, what software is that then ?

 

[momo1501]

I am curious, what software is that then ?

Profibus Master Simulator downloaded from Bihl+Wiedemann GmbH 4.2.29.0
Thank you

 

[JesperMP]

I did not know about this product. I checked on their website, and it seems that it is a combination of software and an adapter called "PROFIBUS-DP UART".
I dont think you can use it with a regular serial port without this adapter.

 

[momo1501]

I did not know about this product. I checked on their website, and it seems that it is a combination of software and an adapter called "PROFIBUS-DP UART".
I dont think you can use it with a regular serial port without this adapter.

To conclude

I need a profinet/profibus/Hart device and an RS232 modem to be able to communicate with the device. Am I right?
What should I use on the PC?

 

[JesperMP]

Profibus uses RS485. I also think that the timing requirements are relativelu stringent, so a simple RS232/RS485 converter will not be enough.
Any Profibus adapter I have seen has been some kind of gateway with internal processor.

Hart is also special. Hart is overlaid on a 4-20mA signal (via a frequency carrier ? I dont know). I only once had to connect to a Hart device, and that needed a special terminal.

 

[JesperMP]

From memory, I think that for a couple of years ago there was a similar thread where someone was making a datalog by listening in to data off a Profinet network.
Since it was on ethernet, it didnt require special hardware.
Cant find that thread now.

 

[momo1501]

Profibus uses RS485. I also think that the timing requirements are relativelu stringent, so a simple RS232/RS485 converter will not be enough.
Any Profibus adapter I have seen has been some kind of gateway with internal processor.

Hart is also special. Hart is overlaid on a 4-20mA signal (via a frequency carrier ? I dont know). I only once had to connect to a Hart device, and that needed a special terminal.

Thank you JesperMP for your help. I am grateful
Could you please tell me what should I need as devices to fulfill the 3 communications across the three networks?

Best regards

 

[JesperMP]

The way I would do it, would be to get a dedicated adapter from a reputable vendor, and an OPC server for the adapter from the same vendor.
And then I would make my application as an OPC client.
But that is not what you want. You want to listen-in (to "snoop" so to speak) in the data between 2 devices.

There are some products for "listening in" to Profibus and Profinet, dont know about Hart.
They are called Profibus or Profinet analyzers.
Of course they are made by specialists that are experts within their fields, and certainly also members of the Profinet/Profibus organisation with access to all the documentation for the same.

I dont know of any vendor with adapters for Profibus or Profinet, that also provide low-level access to listen in to data directly off the bus.

Just as an example, someone has made a huge effort to create a library to communicate with Siemens S7 PLCs, without using Siemens software or hardware (look for Libnodave). It is quite good and used by many as a free alternative to Siemens licensed libraries. But I am certain that it has taken the very talented programmer many years of his life, maybe only in his spare time, but still.
So I think that your task is monumental.

 

[momo1501]

The way I would do it, would be to get a dedicated adapter from a reputable vendor, and an OPC server for the adapter from the same vendor.
And then I would make my application as an OPC client.
But that is not what you want. You want to listen-in (to "snoop" so to speak) in the data between 2 devices.

There are some products for "listening in" to Profibus and Profinet, dont know about Hart.
They are called Profibus or Profinet analyzers.
Of course they are made by specialists that are experts within their fields, and certainly also members of the Profinet/Profibus organisation with access to all the documentation for the same.

I dont know of any vendor with adapters for Profibus or Profinet, that also provide low-level access to listen in to data directly off the bus.

Just as an example, someone has made a huge effort to create a library to communicate with Siemens S7 PLCs, without using Siemens software or hardware (look for Libnodave). It is quite good and used by many as a free alternative to Siemens licensed libraries. But I am certain that it has taken the very talented programmer many years of his life, maybe only in his spare time, but still.
So I think that your task is monumental.

Thank you for your replay
But there are already free solution doing the same thing. See for example https://plc4x.apache.org/ doing the same thing. They developped adapters for the most widely used protocols. How did they test this?

 

[JesperMP]

Thank you for your replay
But there are already free solution doing the same thing. See for example https://plc4x.apache.org/ doing the same thing. They developped adapters for the most widely used protocols. How did they test this?

These are all ethernet based protocols.
For ethernet, all you need as a switch with port mirroring. You can then send a copy off all the traffic between 2 devices to your PC.