Refresh rate issue about uldaq

[FaSoa]

Hello @thojDufour .
Which MCC daq device are you using?

[sbazaz]

Are you using the continuous option (SO_CONTINUOUS)? If that the case, then that's the expected behavior. the scan samples are transferred in multiples of block size from the scan buffer. If you don't like this behavior, you can use the single I/O option with the continuous option, however, you might get buffer overrun error at high scan rates.

[thojDufour]

Hello @FaSoa ,
I'm using both the USB-1808 and USB-1808X.

@sbazaz Yes, I'm indeed using the SO_CONTINUOUS option.
Is there anywhere in the documentation where I can find out the block size of the scan buffer for specific devices?

Let's say for example I set the sampling rate to 10kS/s and I'm polling 100 times a second. I receive therefore 128 samples. But there is only 100 new samples that have happened since last poll. Is it correct to assume that the first 28 samples of the last scan are the same as the last 28 samples from the previous scan?