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Communication problems with 570 after updating Visilogic


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I have some problems with connection between V570 and PC. I can't communicate via Ethernet with v570. But my program written in Java without any problems works with v280.

Earlier, I worked without problem when I have Visilogic, but after programming Unitronics with Visilogic 8.6.1, my program stopped its properly work.

My program connects to the PLC (opening socket), writing to socket, but when trying to read from it, there isn't any answer from PLC.

The same problem was when I used another v570, 100% Ethernet card is working successfully.

Can you help me?

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Hi, Does Visilogic manage to communicate with your PLC?

If only your program fails, then you should check that the checksum in your program is calculated right and that the request you have sent is legal.

If you enter the INFO in your V570 --> Ethernet --> Monitor --> Choose the right port (0 to 3, depends on the port on the PLC you are using), you can see the Tx and Rx buffers.

In the Rx you should see the message that the PC sent to the PLC. You can choose to see the buffers in either HEX or ASCII.

The Monitor shows the message after stripping the "Ethernet Header". In case of a Binary Protocol, you should see that the message sent from the PC starts with /_OPLC

If you see that there is data in the Rx buffer, but nothing in the Tx then it means that either your checksums are wrong, or something else in your message is wrong.

If you don't see anything in the Rx buffer then it means that your PLC does not receive the message and it is therefore a problem with the communication settings in the PLC (Socket is used, IP address changed, port changed, protocol changed, Master/Slave changed).

Please keep me posted about the progress of finding the problem.

I'm not from Unitronics support but actually from their R&D so I'm not always available to help and answers questions, but I do my best.

So if you have any technical question about the communication protocol, you can always forward it to the R&D through out great support.

I hope it helps.

Thank you, and have a nice day.

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