OPC write value issue-IBH opc server

[mariodavid]

Why you don’t pass valid URL to new OpcCom.Da20.Server(url, server)?

Becase I do not what is a valid URL. Could be “http://localhost/Scada/”? I really do not know.

Interface is just a declaration. The runtime executes the method of an object that was actually created.

I am trying to create a class derived from IOPCSyncIO interface. Implementing Something like this:

“private IOPCSyncIO campo;
public IdentifiedResult[] Write(ItemValue[] items)
{
if (this.campo == null)
throw new NotConnectedException();
((IOPCSyncIO) this.campo).Write(items);
}”
without return, because IOPCSyncIO.write is void method

but give me a NullReferenceException

I am trying to create a instance of a interface, but that is not possible.

[mariodavid]

Why you don’t pass valid URL to new OpcCom.Da20.Server(url, server)?

Becase I do not KNOW what is a valid URL. Could be “http://localhost/Scada/”? I really do not know.

Excuse my mistakes when writing

[mariodavid]

I have passed all kinds of values to url: int, boolean, string. The compiler said that: can not be changed to an OPC.URL type.

URL url = 12;
URL url = “nashghda”;
URL url = true;

Only allows URL url = null;

Do you know which is the valid URL to new OpcCom.Da20.Server(url, server)?

[Mikhail]

I suppose the URL here is the ID of the OPC server, e.g. Matrikon.OPC.Simulation/{f8582cf2-88fb-11d0-b850-00c0f0104305}

[mariodavid]

I tried this Opc.URL url = new Opc.URL(“”); Compile without error but appers: error sending command: remote server is not currently connected. There is no exception in the contructor with this meaning. Where do you think is the exception?. I probe it with “localhost” etc. Still the same error

[Mikhail]

Is there a method like Connect to connect to the OPC server?

[danielfernandes]

Hello,
I am using Kepware software for middleware with PLC Omron. The kepware implement the OPC server.
I already can communicate and I read the memory positions of Plc.
Now, I want write in this positions of Plc, but I don’t understand how I can doing.
Can you help me?

[Mikhail]

Hello,

Please create a new topic in https://forum.rapidscada.org/?forum=communicating-with-devices/opc
This topic is not relevant to the question.

Provide information what Rapid SCADA version do you use?
Did you do some settings to write data or have no idea how to do it?

[Author]

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