Error -200486 "specified channel is not in Task"

[richjoh]

persistly get error -200486 after using the DAQmx save Global Task VI or save virtual task to save an existing task. I have the boolean set to True to overwrite an existing class. Saves are only successful if I rename the task. I'm using USB-DAQ6218 for voltage differential Dev2/io0:7,Dev2/io16:23 on these channels.

Have not figure out what wrong here.

[richjoh]

OK correct some issues but Save Global Task does not work with a multi channal list, for example Dev2/io0:7, Dev2/io16:23. If I use a single channel Dev2/io0 saving Global is OK.

[PeterGC]

When you overwrite are you trying overwriting all your channels at once?  Is it possible that you have a channel in that range that you are not using and therefor not being overwritten?

[richjoh]

No problems overwriting channels. Saving multi channel (local) task works just fine. Use the Save Global Task using a multi channel addressing constant control I persistantly get this error. If I subsequently look at whats setup in MAX Virtual Task, its the first channel only e.g. io0 physical channel, voltage measurement etc etc. Btw, using LV2011.

[PeterGC]

It sounds like you need to specify those channels as active in the task.  Try doing it directly in MAX.   Have already you done that?   Or are you saying that once you have specified these channels and try to save over task it reverts to a one channel setup?

Also,  what version of DAQmx are you using?

[richjoh]

I'm running whatever version of DAQmx in LV2011 device driver.

How do I make a task multi channeled and save it as a Global. I'm successful when I save this as a local task. Whenever I use the Save Global Task the DAQmx VI repoorts error -200486, specified channel is not in Task.

The VI below is from NI, if I use a single physical channel in my task all is OK. If I use the multi-physical channel task I get -200486 error.

[PeterGC]

richjoh,

I don't believe that function is saving a global "task", I think it is saving a global channel.  And it looks like only a single physical channel can be configured for each global channel.  What exactly are you trying to do, there may be a better way of going about it.

-Pete

[richjoh]

When the save is successful (using 1 channel) the save is listed under Global Task. I'd expect this to work for multi channel task just as it does with saving a local task. Local task saves multi-channel task just fine.

This is NI's VI, I'm only using a multi-channel for the "channels" input of the VI and it errors.

[PeterGC]

That VI is creating a "global virtual channel", not a global task.  You can only setup one physical channel for each global virtual channel.

[richjoh]

---

PeterGC wrote:

"You can only setup one physical channel for each global virtual channel."

---

Labview Help context:

Tasks in NI-DAQmx

A task is a collection of one or more virtual channels with timing, triggering, and other properties. Conceptually, a task represents a measurement or generation you want to perform. All channels in a task must be of the same I/O type, such as analog input or counter output.

So I should be able to setup mutiple channels in the same Task. So it appears there is a problem with the "Save Global Channel" VI since its "Task/Channels" input doesn't handle multiple channels or is it multiple task (I have no time to verify how it checks for channels or a Task). As you can see the VI above connects a Task (not channel).

Btw, your correct on your physical channel quote but I'm questioning why does the VI throw the error if its not intended to save multiple (physical/virtual) channels to 1 Task. Confusing.