Error -50103 when reading two analog channels

[DavidT]

Hello everyone,

Im getting error -50103 when reading two simulataneous analog input tasks using two analog read vi's. Im able to read the analog signals if i create a multiple channel task, but I have the problem that one channel is RSE and the other is Differential, so my signals are not correct. How can i configure the channels using a single 'daqmx create channel.vi' or do I need different hardware that would allow mutiple channel types?

Im currently using a PCI-6221 card, daqmx 7.4, LV7.1.

Thanks

[Sean_C.]

Hello David,

You are getting error -50103 because you are trying to access the same resources (AI Sample Clock) with two different tasks.  If you would like to acquire data from multiple analog input channels, they must be in the same task.  You can use multiple instances of the DAQmx Create Virtual Channel.vi to individually set a channel's input terminal configuration.  Take a look at the attached example which calls two DAQmx Create Virtual Channel.vi's in the same task to set channel 0 to RSE and channel 1 to differential.  The two property nodes verify that the separate configurations were made.

I hope this helps.  Please let me know if you have any further questions.

Regards,
Sean C.

[Poormanphysics]

Hello Sean can you do that too for analog outputs?

Thanks,

Berns B.

[Tom_W_[DE]]

Hi Berns-

Please see my response here.

Thanks-

[Charlie_Fields]

I am getting this error but for a different reason.

I am monitoring PFI1 for a trigger signal to begin my detection.

I am also monitoring two analog inputs from RTDs on AI0 and AI1.

How can I separate these two functions?  Maybe I need to combine them?!?!