Replay captured voltage data

[JessioM164]

Hi, I have been measuring AC voltages through two channels for 5 minutes at 5000Hz using DAQ Assistant and writing them to LVM files. The LVM files have two voltage columns and a time from start column. I'm now wanting to replay these exact voltages at the same timing/frequency back into the machine I collected them from. I've attached the VI I've been using to collect the data. I'm very new to LabVIEW so any help would really be appreciated, thanks.

[GerdW]

Hi Jessio,

what have you tried so far?

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@JessioM164 wrote:

I'm now wanting to replay these exact voltages at the same timing/frequency back into the machine I collected them from.

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You need a DAQ device capable of outputting the same voltages at the required frequency.

Once you have it then you could read your measurement data and write it to your DAQ device…

[JessioM164]

Hi GerdW,

All I've thought to do so far is change the DAQ assist to output to the two channels after reading in the the LVM file. It seems to put out the signal instantly rather than at the timing I recorded it at, I'm unsure how this needs to be timed.

And I'm quite confident the cards I have in the PXI should be capable of doing this.

(If that's what you mean)

Thanks

[GerdW]

Hi Jessio,

when reading the voltage signals you were using "Finite samples" sampling mode, despite you should use the "continuous sampling" mode.

When outputting the signals you are using the "1 sample hardware-timed" mode.

How does that fit to each other?

Have you done any of the "Training resources"? Have you examined any of those example VIs coming with LabVIEW and DAQmx? Have you ever tried to refuse from using just a bunch of ExpressVIs and use "plain" LabVIEW functions instead?