08-28-2009 04:21 PM
Why doesn't DAQ Assistant show the coerced values of the Max/Min analog input range, instead of accepting whatever I enter into it? In a LabVIEW 8.6 project, if I add a task that defined a group of analog inputs, (NI USB 6229), I can defined the Max/Min values to be (0.1V, 0V), (no scaling). However, when I run the project and look at the AI.MAX and AI.MIN values, I see that they are coerced to the hardware supported range (0.2, -0.2).
Why does DAQ Assistant tell me about the coerced values when I enter them?
This would be useful information when I'm entering it.
08-28-2009 11:06 PM
08-29-2009 09:11 AM
said, "A particular device may only have specific ranges that it can be set to and not any arbitrary analog input range. To know what ranges the device supports, you can look that information up in the device's manual. "
Sorry, I guess I didn't make it clear. I know that a particular hardware device has limited supported voltage ranges. I want to know why DAQ Assistant does not tell me when it will be coercing those values. It lets me enter anything, but then uses something else.
08-29-2009 11:03 AM
My guess is that the behavior of the dialog would be more annoying if it coerced the values. Suppose you select a channel then pick a range. Then you select a different channel that has different ranges that could be selected. How would the dialog handle that. Coerce the values to the new channel? Uncoerce the range back to what you originally selected for the first channel? I think it would feel like you were fighting the dialog box depending on the order you entered in all of your properties. You'd always be wondering why the dialog box doesn't take what you want.
Perhaps what would be better is that instead of coercing, it just gives a note highlight on the box what the possible ranges are.