LabVIEW Synchronizing PXIe-4300,4302,and 4353 with different data rates

[ChronicTiger]

Hi!

I am working with the following hardware:

PXIe-1084 Chassis

Controller - PXIE-8381

PXe-4300 (Slots 2-16)

PXIe-4302 (Slot 17)

PXIe-4353 (Slot 18)

The goal is to synchronize the modules and use a high sample rate for the 43XX modules and sample the 4353 at its highest rate which is 90Hz.   

I've modified the example "Analog Input - Synchroniztion.VI" and it works temporarily.  Shortly after running I get  an error related to the the application not being able to keep up with the hardware - Error -200279

My first question is if I am using the correct technique to accomplish my goal?  If not I would really appreciate suggestions on how to do this properly and without error.

Also, the collected data - won't the data be different lengths?  How do you merge the data to write to a singe file?

Thanks!!!!

I've attached information to help form suggestions for me.

[mcduff]

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@ChronicTiger wrote:

Hi!

I've modified the example "Analog Input - Synchroniztion.VI" and it works temporarily.  Shortly after running I get  an error related to the the application not being able to keep up with the hardware - Error -200279

My first question is if I am using the correct technique to accomplish my goal?  If not I would really appreciate suggestions on how to do this properly and without error.

Also, the collected data - won't the data be different lengths?  How do you merge the data to write to a singe file?

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If the example works then it is the correct method.

Issues:

1. You are collecting the same number of samples, 50, for both your tasks. For a sampling rate of 1000 Sa/s this is a 20 ms period, for a 90 Sa/s this is about a 500 ms period? Do you see an issue? Suggestion, set the number of sample for a 100ms time period, so 100 for 1000 Sa/s and 9 for 90 Sa/s. This should sync your acquisition.
2. The data will be different lengths. I like the automatic TDMS logging for DAQmx. Since you have multiple tasks you will have multiple files. If you want the data in the same file, look at producer consumer templates.

mcduff

[ChronicTiger]

mcduff,

Thanks for your time and insight!  I will try your suggestions out and let you know how it works out.

Thanks again,

Chronic