USB-6255 and C# DAQ Question

[JustAProgrammer]

Hope this is the right location for this inquiry.  I need to read in AI data at a fairly quick rate I would call it deterministic more so than real-time as I am will be using XP as the OS and a managed VS.Net language, my question has to do with acquiring the data and how fast it can be acquired.  What is the fastest data can be streamed from the 40 differential analog inputs into memory from a USB-6255 using C# on a XP machine?  I know there are other factors that will come in to play but generally what are some rates seen on say a Quad Core processor with 4GB or ram.  I see the specs on the card are 1MS/s with 4095 samples listed as the onboard memory, is that 4095 MS? Basically I need to know that the fastest data can be acquired over 20 channels of differential analog input into a PC via a USB-6255 running XP SP3 using Measurement Studio .NET before data loss is an issue.  Can data be acquired/streamed into the PC memory at 1khz/channel over the 20 channels?  

[JustAProgrammer]

I am thinking that it may be possible using the ContAcqVoltageSamples_IntClk example, but want to make sure that the device in question can do the task with a pc spec'ed as above.

[Dennis_Knutson]

The specs for the card are actually 1.25 MS/s but that is for a single channel. The max aggregate rate is 750 MS/s so divide that by however many channels you are going to use. That is how fast you can acquire. If your pc does not have a Hi-Speed USB port, then you would have problems. See this.

When the spec says 4095 samples, it means 4095 samples. It's not a typo.

[JustAProgrammer]

I knew that according to the specs that essentially I could get (750Ks/s)(/20 Channels) = 37Ks/s capability so I guess I should have phrased my question a little different and asked if you can acquire/stream that amount of data into the PC via USB 2.0 without dataloss for an extended period of time.

If the spec is the tested rate of data transfer per second over USB then that answers my question.  I was reading that as the card capable acquisition rate and not thinking of it as the acquisition and transfer to pc rate.

Thanks.

[Dennis_Knutson]

The spec is the acquisition and transfer rate. Wouldn't make much sense to me to spec just what the hardware can do and not be able to transfer it. Sort of worthless spec.