On a NI6534 card, may I change the REQ period when continously outputing data ?

[Chris_K]

The NI6534 card can continously outputing data by enabling the onboard memory looping mode of NI 6534 devices. In that specific case, is it possible to change the datastream frequency by using the command "DIG_Block_PG_Config (deviceNumber, group, config, reqSource, timebase, reqInterval, externalGate)" without interrupting the dataflow and reload the data to the memory?

[RIO-Todd]

Greetings Chris K,

You will not be able to use the DIG_Block_PG_Config function to change the REQ frequency on the fly. You will have stop the pattern output operation, reconfigure the pattern generation, change the REQ frequency, and then restart the operation.

If you are needing to change the frequency of the pattern generation on the fly, another option would be to use an external clock for the pattern output operation. You could use a counter/timer device to generate a clock signal (you can change the frequency of an output signal from a counter/timer on the fly) and use that clock as external clock for your 6534 pattern generation. We have counter/timer devices that I've linked to below.

PCI-6601
http://sine.ni.com/apps/we/nioc.vp?cid=3589〈=
US

I hope this helps.

Regards,

Todd D.
NI Applications Engineer