Error message -200077 when running GenMultVoltUpdates-Int Clk.vi with PCI-6703

[M_Vrinkle]

Hello,

I would like to run different voltage signals on the 16-channels of my PCI-6703 DAQ board and update them dynamically. Gen Mult Volt Updates-Int Clk.vi seems to provide a basic template.

However, when attempting to run the basic program with the PCI-6703, I get the the following message: 

Property Node DAQmx Timing (arg 1) in Waveform Buffer Generation (multi).vi->Gen Mult Volt Updates-Int Clk.vi
Property: SampTimingType
Requested Value: Sample Clock
You Can Select: On Demand

Task Name: _unnamedTask

I don't know where to select "On Demand" from the timing DAQ block. Does this mean that the PCI-6703 doesn't support sample clock updates? I know that there are some postings on this forum suggesting to uninstall and reinstall LabVIEW, but before I do that I would like to make sure of any other possible solutions.

Actually, if I try running this program on a different DAQ card (the PCI-6259) there is no such error, but instead there is a different one -- -200220.

Please help! Thanks!!

[Travis-E]

Hello M_Vrinkle,

Unfortunately the PCI-6703 can only be timed through software. This means that what you will have to do is remove the Timing function from the code and allow writing to the Analog output to be updated depending on the wait time in the while loop where you place the write function. Any code that involves setting a sample rate cannot be used with the PCI-6703.

Regards,

[M_Vrinkle]

Hello,

Thanks for the suggestion.

Let me see if I can get this straight -- do I just remove the timing function (DAQmx Timing (Sample Clock).vi) from the program or if there are more steps to take? I do want the Analog output to be updated in real time, and I also want the output rate be the same for all of my waveforms (I would like to output 16 voltages at once, say at the rate of 1 sample/millisecond). Where can I specify the output rate?

I have tried just removing the timing function from the GenMultVoltUpdates-Int Clk.vi, but I still receive the same error. Any ideas?

Thanks for your help!

[Travis-E]

 Hello M_Vrinkle,

When you use the Waveform data type DAQmx tries to internally create a clock and go the speed necessary to output that data. Since you cannot generate a clock internally with your device you cannot directly use Waveform Data. The "Voltage_On Demand Output.vi" is a good starting point for development. It writes one data point to each channel of your device depending on the value you enter into the data array on the write node. I hope this is helpful!

Regards,

-Travis E

[M_Vrinkle]

Thanks for the tip! Now that I know that I can't use a clock with my device, and hence no Waveform Data, I will try to figure out something else.