Disabling a channel

[Eagle01]

The harware I am using is PXI-4461.  I am writing my application in Microsoft Visual Studio 2005 using DAQmx functions.  I have one task that contains both ouput pins.  I want to be able to run buth pin or be able to run either pin by it self.  Basically I want to disable one of the pins,  but I want to do this all with out creating a new task and rewriting the data to the pin.  Is there an easy way to do this or is there a trick I can do with the triggers to prevent one of the channels from running.

[David_Pratt]

Hey Eagle01,

There's no way to control which channels are active or not active once a task begins.  Since you're not wanting to have to reload the task each time either, you can't programatically control which channels the task use or don't use.  I would suggest approaching a post-processing method, taking an array out and only grabbing the data important to you once it's established.  Your best way though would be to use a state machine architecture that will perform or load the channels you want or don't want to work and then read.  Let me know if you have any more questions.

Thanks,

[Eagle01]

I don't want to change the task while it is running a want to change it before I start it.  The function that writes out the data(DAQmxWriteAnalogF64) takes50 Milli-seconds to return.  I want to try to get this wait time only in init and not have to have it every time I run.

[David_Pratt]

Once a task has been initialized there is not a way to enable or disable individual channels or pins without stopping, modifying, and restarting the task or changing to a seperate task.  If you're looking at a way to not slow down your program's acquisition, you'll need to do the post processing method I previously mentioned.