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Callbacks in service vs GUI

08 Jun 2018 14:49 #6408 by support
Replied by support on topic Callbacks in service vs GUI
this certainly is not related to licensing. The trial license works the same in this respect.

In fact, we also do not do anything differently when running as a service vs GUI, so what you describe is quite unexpected.

Can you give some details? Such as:

1. Does this also happen with code taken from our examples, connecting to our public server?

2. Which OPC server are you connecting to?

3. Can you post here the piece of code that makes the subscription, and perhaps the skeleton of the event handler?

4. Isn't there something in your event handler that slows it down? The event handler is only called in a serialized way - meaning that until you are finished with processing of one event, it cannot start processing another one.

Thank you

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08 Jun 2018 14:45 #6407 by support
From: OPC Labs Contact Form - K.
Sent: Friday, June 8, 2018 12:52 PM
To: Z.
Subject: OPC Labs Contact Form - Callbacks in service vs GUI


I am evaluating your QuickOPC kit and have a question.

When making a Delphi VCL application everything wokrs fine and I get DataChange eventsevery 100ms.

When subscribing on the same tag in a Delphi service I get DataChange events every 1.5 s. What is the reason for this slow procedure?

I am evaluating your software so if this is something that only happens in the "free" version it would be nice to know. The only thing I have seen so far regarding the limits for the free version is that it only works for 30 minutes.

I am looking forward to your reply.

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