Stream data to disk (LabVIEW RT and NI PXI-5122)

[Gerald_Schaller]

I'm planning to acquire a signal at a rate of 20MS/s during 10 Minutes. I thought about buying a PXI Chassis containing a digitizer PXI-5122 and a controler PXI-8174 running LabVIEW RT. Is it possible to stream the data to disk or to another HOST PC with those requirements ? Does anybody have onother hardware solution ?

Thanks in advance for any answer ?

[David S]

Hi Gerald,

If you acquire data at 20MS/s with the PXI-5122, you will need to stream a little over 38 MB/s. The PXI bus should be able to get the data from the PXI-5122 to the PXI-8174, but you may run into some problems transferring that much data over the Ethernet. If you do encounter network bandwidth issues, you will need to store the data directly on the PXI controller.

The best way to store data at that rate is to use a RAID. Unfortunately, I have not seen a CompactPCI or PXI RAID. The best way to use a RAID with a PXI system is to use a PC to control the PXI system over MXI-3. This way, you could put the RAID in the PC and stream data directly from the PXI-5122 to the PC and to the RAID. If you use this method, you will not be able to use LabVIEW RT.
I hope that helps.

Regards,

David Shatila
Applications Engineer
National Instruments