why not use USB 6008?

[TommyBoy]

Hi,

I have an application that requires me to sample 6 AI channels at 1 kHz.
Processing every 20 ms.
I also need to output a PWM on 3 channels.

Normally I'd use PCI-DAQ cards.
e.g. a PCI-6023E and a PCI 6601 (timer/counter).
This costs about 700€.

Why shouldn't I use a NI USB 6008 (145€)
and two NI 6501 (99€).

Is there a big difference in programming and performance?

Are those devices all USB-2?
Because If I sample at 10Khz, I do not suppose that all that
data can go over a USB1-bus.

Thx !

[Tiptop]

Hi!


My observation is that a 6008 will work for you if you only need to acquire 6 channels at 1 kHz and you can handle 11 bits of resolution (to use six channels you must be in single ended mode, which losses one bit of resolution on this board). The other possible disadvantage of the 6008 is that you will have to learn to use DAQmx Base, if you haven't done so yet. However, if you are familiar with DAQmx, this should not be too difficult.

As for digital output, using two 6501's may not work for you. They will be software timed digital outputs, where it seems that you were looking for hardware timed outputs before (6601).

Both of these devices are USB 2.0 Full-Speed, which can handle this amount of data.

Good Luck with your project!

Justin