Messaging Using Queues and Notifiers

[Jim Kring]

Hello LAVA folks,

I wanted to invite anyone who is interested, to take a look at a new tool that I created. I call it a "Message Queue". The nice thing about this queue, is that when a message is enqueued a response notifier may be obtained. Then, when the message is dequeued by the message handler, the same notifier is returned. Finally, when the message handler is finished processing the message, notification can then be sent back to the message generator.

You can download the tool at:

http://osdn.dl.sourceforge.net/sourceforge...eue-6.0.1.0.zip

The download includes a simple calculator example and installation instructions. It is packaged so that you can just drop the tool into your user.lib folder and a pretty palette will appear. Let me know what you think. Obviously this doesn't solve all messaging problems, but it does address simple message and response needs. I am interested in your feedback and seeing any interesting examples and use cases that you come up with.

-Jim Kring

[m3nth]

That link didn't work for me but this one did :arrow: FTP Link

[ashwin]

Hi Jim,

I am trying to receive a DATAREADY message from a USB based DSO ASB3000 using its driver DLL.

Can u tell me how to use ur VIs for receiving a message from a Device?

Tnx a ton

Ashwin

QUOTE(Jim Kring @ Oct 22 2002, 11:20 AM)

Hello LAVA folks,

I wanted to invite anyone who is interested, to take a look at a new tool that I created. I call it a "Message Queue". The nice thing about this queue, is that when a message is enqueued a response notifier may be obtained. Then, when the message is dequeued by the message handler, the same notifier is returned. Finally, when the message handler is finished processing the message, notification can then be sent back to the message generator.

You can download the tool at:

http://osdn.dl.sourceforge.net/sourceforge...eue-6.0.1.0.zip

The download includes a simple calculator example and installation instructions. It is packaged so that you can just drop the tool into your user.lib folder and a pretty palette will appear. Let me know what you think. Obviously this doesn't solve all messaging problems, but it does address simple message and response needs. I am interested in your feedback and seeing any interesting examples and use cases that you come up with.

-Jim Kring

[Rolf Kalbermatter]

QUOTE(ashwin @ Jan 26 2008, 09:32 AM)

Hi Jim,

I am trying to receive a DATAREADY message from a USB based DSO ASB3000 using its driver DLL.

Can u tell me how to use ur VIs for receiving a message from a Device?

You can't.

For a driver to inform you of something it must implement some kind of event notification. For DLLs there are two possible solutions, they can either allow you to install a callback function that will be called when an event occurres or they can use OS events to inform the caller about such an event. In any case these are things that are not directly translateable into LabVIEW events so you will basically have to write a wrapper DLL that calls your Device DLL with the event notification method that your driver uses and translates it into something more LabVIEW friendly such as a user event or occurrence.

C programming knowledge will be required for sure to do that.

Rolf Kalbermatter