PCI-6723 voltage output drop observed for 8 channels coninuous updation at 100ks/sec

[embedded systems engineer]

Hi all,
Iam working on labview 7.1 NIDAQmx7.3 and pci-6723 card.i am generating 8 analog outputs simultaneously,and the voltages and frequency can be changed during fly.The problem is during the run time iam observing some voltage drop of 1mv to 4mv this is really worst for me .out of 8 channels 6 are dc voltages, for these channels also iam sampling at 100ks/sec.is this really a problem.bcos dc voltage needs 1 sample also.if sampling is the problem how can i change individual channel sampling frequency or number of sampples,gothrough the attachment please.

THANKS AND REGARDS
LABVIEW BOY

[Dr._Imad]

I am not sure what is causing that.
But for the dc signals, use instead the daqmx functions that outputs DC. what your are doing is generating a DC from a waveform (simply by setting its frequency to zero). Genration is still performed even though it is DC.

You should have 2 sets: the waveform channels (0,1), and the DC channels (2:7), each set has its all initiallization and output function (in the same vi, or 2 vi's, does not matter)

[embedded systems engineer]

Hello Dr Imad,
Thanks very much for your response.by your ideas i implemented the new vi ,in the same vi i have to utilize the daqmx write source 2 times, then there will be generally conflict which results in NOT SUPPORTING of multiple writes.can u please update my vi and send so that ican clear off the doubts.

Regards
LABVIEW BOY

[Dr._Imad]

Here is the modified vi. Hope it works or at least illustates the idea.