pattern generation doesnt work - DIOHS96

[Gabi1]

Hello

I have a trouble getting the DAQmx to do a pattern generation as expected.

the first mode of operation, is when i set the clock configuration to "sample clock": the card should support 2MHz operation, however, above about 2KHz, the card spits out everything BUT the last 16 samples! . the error i get is underbuffer, when i force the task to stop after having waited too long. above 1MHz the output operation dies in the middle, underbuffer error.

to note, i monitor all the time the data written to buffer, and the actual nb of samples generated. i see that i have written a nb of samples, that the memory has filled, that it recovers as the data is spit out, and that suddenly, 16 bits from the end it stops.

the second mode of operation, is by setting the clock configuration to " burst (input)", after the recommendation of Johannes from this same forum (by the way, i still want to understand why first mode of operation doesnt work). then, on most computers installed with same card the system works nicely, and i get 2MHz operation working.

But for one computer: a new HP, which had a bug already not recognising the NI card first, but after the bug fix from knowledgebase it recognised it. it seems this card work using traditional DAQ now on this specific computer.

What happens on this computer is that the "sample clock" configuration works as on any other computer, meaning badly. and the "burst input" mode, doesnt work at all. it spits out only the first 16 samples, then dies. i have to stop the task manually.

so you can check that i make no mistake, i attach my piece of code that does the work.

Hope that i get help fast! thanks

OOPS! this should have gone to hardware board! - disregard!

Message Edited by Gabi1 on 05-10-2007 04:56 AM