6008 two channel measurement

[Jaspal]

Hello,

I am using NI USB 6008 to measure a voltage and a strain signal and analysing them in real time. I am using channel 2 and 3.

I have two VI's. One for analysing the strain signal and other for anlaysing the voltage. I want to merge these into one vi so that I can compare two graphs from analysis of both these signals in real time.

Labview gives an error if I run both VI's separately or have the code pasted in 1 VI.

Is there a separate way to achieve what I am doing.

I am using DAQ assistant to measure these signals.

Thanks

[Dennis_Knutson]

What is the error that you get? Are you actually using two DAQ Assistants? If so, then you need to have a single DAQ Assistant with multiple channels. In one of the DAQ Assistants, just click the 'Add Channels'.

[Jaspal]

Hi Dennis,

Originally I was using 2 DAQ assistants. Then I used just 1 to acquire both signals.

Although it works, both signals are acquired at same sampling rate.

I want to acquire one at 1khz and the other at 100hz. Although I can acquire both at 1khz, my VI si designed around 100hz sampling rate.

Looks like my only choice is to acquire both signals at the higher sampling rate.

Does that make sense?

Thanks

Jas

[Dennis_Knutson]

Yes, that is your only choice. You can easily decimate the data array to reduce the number of samples.