running two DAQmx AI tasks concurrently on a single device

[Brian.Bassett]

Hi,  Is is possible to run two DAQmx AI tasks concurrently on a single device such as a PCI-6225.  For example, say I wanted task #1 to scan analog channels 0-39 at a "slow" rate to update the display at a refresh rate of approximately 4Hz.  At the same time, I wanted task #2 to scan analog channels (from the same device) 0-2 at a "high" rate of 10kHz.  Is this possible?  If not with the PCI-6225 how about with some other NI hardware? Thanks, Brian 

[Dennis_Knutson]

This question gets asked a couple times a week it seems. The answer is no, you cannot run two separate tasks. You have a single clock on the board and all of the inputs are muxed to one A/D converter. The standard asnwer is to scan at the fastest rate and in yuor software, discard samples you don't need.

[G_Lo]

Btb,

Running two tasks for the same card is not going to be an option but this knowledge base includes a possible workaround for using one task.  Keep in mind that this workaround is essentially "tricking" the card to achieve different sample rates which have a common divisor.  The samples taken will not be truly simultaneous, though.