Digital output write lag

[niUser88]

Hello,

I hope I am writing in the correct location.

We use .NET C# NIDAQmx API for Windows to write to NI 9472 digital output module with WriteSingleSampleMultiLine or WriteSingleSamplePort.

Normally it takes around 1ms to 2ms to write, but occasionally it goes up to 10, 15ms or even more. Is this normal behavior? We have no problems with a couple of milliseconds, but this occasional lag is really limiting our application.

All drivers are up to date. We also tested with official examples and tried Python and C and got the same results. Thanks!

[rolfk]

Yes it is normal. Your application is running on Windows, a distinctively non-real-time enabled OS. Windows can decide to suspend your process at anytime, for any of several thousand reasons, when it thinks it has to do anything more important, such as scanning your hard disk for "very dangerous" viruses or intercepting network messages to see if they are from a bad actor. And this suspension is typically in the range of several ms but can be 100ds of ms or more without violating any guarantees that Windows doesn't give you.