Professional OPC
Development Tools

logos

lupa

Online Forums

Technical support is provided through Support Forums below. Anybody can view them; you need to Register/Login to our site (see links in upper right corner) in order to Post questions. You do not have to be a licensed user of our product.

Please read Rules for forum posts before reporting your issue or asking a question. OPC Labs team is actively monitoring the forums, and replies as soon as possible. Various technical information can also be found in our Knowledge Base. For your convenience, we have also assembled a Frequently Asked Questions page.

Do not use the Contact page for technical issues.

  1. Forum
  3. Discussions
  5. QuickOPC-UA in COM
  7. Reading, Writing, Subscriptions
  9. ReadMultipleValues exception

ReadMultipleValues exception

More
29 Jan 2020 15:15 #8178 by support
Replied by support on topic ReadMultipleValues exception
Hello,

have you regenerated the unit files for the QuickOPC assemblies from the new type libraries (see documentation)?

Best regards

Please Log in or Create an account to join the conversation.

More
29 Jan 2020 15:05 #8177 by Boris
ReadMultipleValues exception was created by Boris
Hello!

I'm using Delphi XE8. I tried to upgrade from version 2018.3 (5.54.1281.1) to version 2019.2 (5.56.475.1). Immediately after the update, a critical error occurred while executing the ReadMultipleValues function.The error occurs only when reading a tag with data type "18 [ExpandedNodeId]" from the UA AnsiC Demo Server (I did not test with other UA servers).
The problem is easy to reproduce using your demo project "..\OPC Labs QuickOPC 2019.2\Examples-COM\OP\UADocExamples\_EasyUAClient\ReadMultipleValues.Main.inc". You need to take this example and change part of the code, like this:
ReadArguments3 := CoUAReadArguments.Create;
ReadArguments3.EndpointDescriptor.UrlString := 'opc.tcp://PC_NAME:48020';  // AnciC UA Demo Server
ReadArguments3.NodeDescriptor.NodeId.ExpandedText := 'ns=4;s=Demo.Dynamic.Scalar.ExpandedNodeId';
Now this project will always end with an error of EAccessViolation.
In the old version, this error does not occur.
Attachments:

Please Log in or Create an account to join the conversation.

Moderators: support
  1. Forum
  3. Discussions
  5. QuickOPC-UA in COM
  7. Reading, Writing, Subscriptions
  9. ReadMultipleValues exception
Time to create page: 0.042 seconds