usb-6009 daq 2 inputs

[Herman Malan]

Hello

I am currently using a usb-6009 with labview 7.1 and DAQmx 8.1 to read data into a LVM file at a sample rate of 40kHz.  Everything is working perfectly when I'm only reading one channel.  Problem is I need to read 3 channels and when I set the DAQ assist to read 2 channels, the max sample rate is 24kHz, which is not sufficient for the problem.

I then thought that I could manage by just reading one channel at a time at 40kHz(using digital input to determine which channel).  Is this possible?  When I set up the DAQ assistant with more channels, I am unable to select a 40Khz sample rate.  I know you can't open multiple DAQ assistant for analogue inputs, so I tried to overcome this by creating a main program with subprograms, each using one DAQ assists, but still got the error:  "The specified resource is reserved. The operation could not be completed as specified.".

I tried to set it up without the DAQ assist, but got an error: Task specified is invalid or does not exist"(error code 200088) which seem to be a known an unfixable problem on labview 7.1. (also I am guessing I will get the same error of the resource is reserved as I did in DAQ assistant)

Is there any way I can set up one program to read an analogue input at 40kHz on one channel and then switch to another channel and do the same?

Thanks

Herman

[Dennis_Knutson · Accepted solution]

Sure, but you have to stop and clear the previous task before starting a new one. You obviously have not done that since you are getting that error.

[Herman Malan]

Thanks, that did the trick.  I previously only set a stop task function.

You'll have to forgive me for my stupid mistakes, I've only been using LV for about 3 days, really appreciate the help.

Herman

[DAQmx Error]

Where is the solution to this

[Dennis_Knutson]

The solution is described above. I don't know what else you might want.