Controlling the same output from multiple locations in vi

Question

Hi
I have a very basic question which I do not seem to find the answer to though.
When programming a VI for measurement and control using a standard DAQ device, for example 6281 I
often want to control the same digital out pin from various places in the program.
F.ex. In the beginning I want P0,0 to be high, then later somewhere deep in the program in a while loop I want
to set P0,0 to low. How do I do this. I keep getting the message that the resource is reserved.
This I have the same question with AI, AO and Digital in.
The DAQassistant does not work and doing this more manually by creating a task, stopping it and clearing it has been problematic.
Can anyone help? Hopefully with a demonstration VI if you have it?
Thanks for reading all the way down though  

Answer 1

You should create a functional global that stores tasks for each port.
In the following image I have some code that should work.
It looks up the addressed port and creates a new task if needed, otherwise it will call the old task.
Be sure to call this VI with 'Stop?'=True at the end of your program.
Ton
Message Edited by TonP on 10-11-2008 08:41 PM
Message Edited by TonP on 10-11-2008 08:42 PM
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