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Broblem with property node and DAQ-card

Hi!

I am using NI DAQ-card to control mini relays and I have a following broblem. I use a "binary" button to control the DAQ-assistant and so on the relays. I have made property node of the "binary" button and set it to value mode(write). When I change the value of property node, the "binary" button in user interface works properly, but the the relay doesn't change the state.
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Message 1 of 5
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There is insufficient information to really determine the problem without seeing the code.

If you use an event structure to sense the value change, you need to write a signaling value property, not just a plain value property.

Please attach a simple version of your code. Have you tried to monitor the code using execution highlghting?
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Message 2 of 5
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Here is the example code of my broblem.

There is a speed measurement and with speed the limit button you can set the limit for the speed. When function is turned on, it should stop the system when speed limit is exceeded. Buttons works properly, but relay doesn't change the state.
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Message 3 of 5
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up
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Message 4 of 5
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The boolean array constant that you are writing to the property node is empty. That is it has been defined as a boolean array, but it has no elements.



The array constant on the left is an empty boolean array. Notice that all teh boolean constants are grayed out. This indicates that none of the constants are 'active'. The array on the right contains 8 active elements. Note that the 8 elemants are more solid in color adn the the 9th element is grayed out.

What you need to do is define your boolean array with the proper constants to turn on or off the proper digital lines.

Ed

Message Edited by Ed Dickens on 05-25-2005 09:15 AM



Ed Dickens - Certified LabVIEW Architect - DISTek Integration, Inc. - NI Certified Alliance Partner
Using the Abort button to stop your VI is like using a tree to stop your car. It works, but there may be consequences.
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