Data acquisition from ZStar3

[slegal]

Hi Freescale's developpers,

I bought the developpment board: ZSTAR3 and when I use the GUI and especially demo acquire data software, I don't have enough samples in the .xls file.

For example, in the attached file.

I lost a lot of samples indeed the duration between 2 samples isn't same (1/30=33ms). Is it normal? Else do you know what is the root cause? Data transfert from pod to dongle, GUI....

Thanks in advance for support.

Regards,

Slegal

test_accelero.txt 

Message Edited by t.dowe on 2009-09-04 02:00 PM

[Epokh]

Hi have you tried to change the sampling frequency?

Have you tried to also switch to comma separed format?

Another possibility is the data buffer is not being flushed properly on the USB connection, but I have no idea about how to check it.

I'll do some test with my kit as well.

cheers.

[Gargy]

Hi ZSTAR3 users,

 this normal behavoir of Zstar3. This cause a power managment of Zstar3 sensors, when the measured sample is nearly same as last transfered the sensor discard the current sample and prepares itself to read another one in next time. So there is restriction that sensors can discard only 10 samples in line and then sends sample always.

This feature can cause real sending frequency down to 3Hz.

But there is no problem becase all samples ar stamped by very precision time stamps (4us step). And all missing samples could be restored in PC.

Have a nice day