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Hello,

I getting problems to run the example of two menus (P3Speller_Menus.prm). When the matrixes change, the flickers appear in a very fast way till the application is stable. It seems the system is reading the input signal while the matrix is chargering and it starts to flicker once it appears (instead of waiting till the matrix appears). After few matrixes change, I got these error:

2011-11-17T17:24:37 - Warning: DataIOFilter::EvaluateTiming: Roundtrip time approaches block duration (currently 89.73%).
2011-11-17T17:24:51 - DataIOFilter::EvaluateTiming: Roundtrip time consistently exceeds block duration (currently 201.71%).

I am using a quite powerfull computer. Nevertheless, I have done the same experiment with the SignalGenerator and it works. I guess it is happening due to the NI Adquisition Card, but it should work. Could someone help me?

Thanks in advance.

Thank you for reporting this problem.

Version 3.0.3 has a problem with changing matrices. Changing matrices causes a large time delay, which is blocking the system, so a considerable amount of data will accumulate in a buffer. Once the delay is over, accumulated data will be released from the buffer all at once, causing the fast flickering.
It does not appear with the SignalGenerator because that simulates data acquisition by waiting for an appropriate time, which is never less than the duration of a data block.

To alleviate this problem, you might either switch to Version 3.0.2, or compile the latest source code from SVN.

Regards,
Juergen

Hello Juergen,

I have updated to the last source code and compiled it. It works fine now.

Thanks.