Q: Acquiring data using two E series devices connected by RTSI and streaming the data to disk

[manvic]

I use two E series PCI Cards, connected by RTSI. I'd like to stream the data to a file and add a header. I also need to read (plot) the stored data, with another VI. It's like having combined "Two E-series Shared ScanClk.vi" & "High Speed Data Logger.vi" into another VI.
Has somebody by chance already done it? TIA

[Photon_Dan]

The answer is yes! We at PrimeTest are asked to do things like that all the time. Currently there are several systems we developed that 1) Use RTSI 2) Stream to disk 3) Plot acquired data.

I have developed one system that acquires data continuously on 16 channels, performs FFTs every 0.4 seconds, updates live plots and streams to disk. 8 channels are on each DAQ device and there is a RTSI cable connecting them.

First, I would have to tell you that there are companies like PrimeTest out there to help you. That stuff is what we do everyday and we are experts. I know LabVIEW is marketed as simple, fast, easy, fun, etc.... but, it sometimes comes down to your application and what you want might be somewhat challenging. Paying an Alliance Member to help
you is almost always a time saver and a money saver since you know it will be done correctly... the first time. OK, editorial over.

Your observation about combining the two examples is very good! I would suggest that you do that in one hierarchy and set the top-level VI to run in another execution system (i.e. data acquisition). Then, construct another top-level VI for your GUI. That GUI can house the plot and start / stop controls. Use a queue to transmit the data from your AI Reads to the GUI thread. The GUI just has to check the queue for data updates and post them to the plot.

Daniel L. Press
PrimeTest Corp.
www.primetest.com