NI PCI-6111 On-Board Memory vs Qty of data

[Barrette]

Hi,

I'm planning to buy a NI PCI-6111 card but I don't know how to interpret what "On-Board Memory : 8192 samples" really mean.

My application require that both channels of the PCI-6111 card read simultaneously scans of 262k samples two or four times per second (524kS/s to 1.048MS/s each channel simultaneously).

Does 8192 samples of FIFO buffer memory size is enough ?  (The PCI-6111 card will be used in a Intel Core 2 Quad processor PC with 4GB of RAM @ 800MHz running LabVIEW 8.5).  Is this "On-Board Memory" is only there in case the PCI bus is busy ?  Does it limit the quantity of data that can be send to the PC ?

Thanks for helping.

Frank

[Brooks_C]

Hello Frank,

I understand your confusion with this specification and it’s because the FIFO size is really more of a low level specification.  It's true that having a larger FIFO increases the maximum sample rate by reducing the number of direct memory access (DMA) transfers the card has to make each second, but this specification is essentially masked by the sample rate specification.  The PCI-6111 is capable of reading at a rate of 5Ms/S/ch meaning that you can read up to 5 Ms/S on each channel so the 524kS/s/ch or 1.048Ms/S/ch you need won't be a problem.

If you need any more specifics please feel free to ask more questions.  Have great day!

Cheers,

[Barrette]

Hello Brooks,

Thank you for your explanation.  Very clear and helpful.  I will place my order in confidence that the product will work for my application.

Thank you again and have a great day too!

Frank