I think NI needs to realize that with the latest round of high-speed DAQ cards, they've broken the back of the PCI/PXI bus. The PCI/PXI backplane, in reality, will only handle 70-80 MBytes/sec. Continuous 60 MS/s of 12-bit or better data is 120MBytes/sec.

What we have used for high data rate xfers is the ICS-554 from ICS Ltd. The cards are expensive, but they have LabVIEW support on both Windows and Linux. AND with a 66MHz, 64-bit PCI 2.2 interface they can keep up with your data rate.
http://www.ics-ltd.com/info/ productInfo.cfm?ID=10&prod=1&info=Analog%20Input%20Boards.



Richard


On Tuesday, February 10, 2004, at 06:30 AM, E. Blasberg wrote:

Hi All,

This may sound naive, but I have a customer who wants to sample up to 6 channels across 3 boards (2 channels/board) at a sampling rate of 10 Megasamples/sec/channel (i.e., 60 MS/s in total).

Three different units are being measured simultaneously, which is why 3 boards are necessary (they don't all start or stop at the same time, but they could all be on at the same time).

Currently the system measures 50KS/s/channel with no problem (plus up to 2 channels of AO). The data is averaged each second and put into a FIFO buffer which is usually 2 minutes (120 samples) long. Every 2 seconds, the FIFO is averaged (to get a running average). I should add that a GPIB data logger is read every 2 seconds for slower data.

My NI rep has suggested the PCI-6115 whose specs could certainly handle this. What I'm worried about is the computer keeping up with averaging 60MS/s.

Anyone have any experience using these data rates over an extended period of time (measurements can last WEEKS).

Much TIA,
E. Blasberg
iDAQ Solutions Ltd







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