Hello Everyone,

I have been working with the XDK from past 2 months and thanks to the community from which i have clarified most of my doubts. I am keenly interested and working in data transfer over wifi.

I have some basic questions relating to the accelerometer BMA 280, now if i am setting the Bandwidth of BMA280 as 500 hz it means that i am sampling it at 1K hz and accordingly i can accumulate/read 1000 samples of raw data per second. And i want to store all the samples of data along with the timestamp or just display it on the console at first step , is it possible ?  

And also there is problem in updating the workbench from 1.3 to 1.4 and i am not inside BGN.

Can anyone please help me with these things?

Thanks
-Mirza
0 (0 Votes)
Accumulation of all samples of raw data along with timestamp?
Answer
12/7/15 12:24 PM as a reply to mirza qadir-baig.
Hi Mirza,

good to hear that you are interested in working with the XDK.

Your assumptions about the accelerometer are correct.

To read the output data with 1KHz, create an autoreloading timer with OS_timerCreate and set the expiration period to 1 ms.
To log the data with timestamp to the XDK-Workbench console, simply use printf and OS_timeGetSystemTimeMs.
If you want to store the data on the SD card or send it via network connection, you may want to use a buffer since the minimum write interval for the medium may be over 1 ms.

The workbench problem is caused by issues with the updating process on our side. The development team is working on it. I will let you know when the problem is fixed.

Did this information solve your issue?

Kind regards,
Manuel
0 (0 Votes)
Accumulation of all samples of raw data along with timestamp?
Answer
12/8/15 1:38 PM as a reply to Manuel Cerny.
Hi manuel,

Thats Exactly what i did. But for every 10ms read of values i am able to print only 7 values, i think that is because the data read out time plus time to prints exceeds 1ms, so i am working with ping pong buffer to get all samples.

And i am working on the application with UI similar to sensor monitor but with added controls and the new modes for analyzing the data sent over wifi.

Also i have some more doubts,
1. I used printf statements with no arguments to check the flow of the program, but everytime i load the application on XDK the print statements  does not get displayed on console, they are just getting ignore, why is that so?
2. About the program i said to read the samples of BMA280, i have used the  OS_timeGetSystemTimeMs in printf statements and everytime there is an offset required for XDK startup which is not constant, Is this normal? to overcome that i am using interrupt to start logging the data, 
3. I think we cannot have the real time timestamp on the XDK right?

I read about the sensor monitor plugun in the 1.4 version, waiting for the update !

Thanks for the reply and waiting for the reply!

Regards
-Mirza

 
0 (0 Votes)
Accumulation of all samples of raw data along with timestamp?
Answer
12/10/15 9:31 AM as a reply to mirza qadir-baig.
Hi Mirza,

I think your ping pong buffer solution is the way to go here.

Let me try to clarify your other questions:
1. & 2. Every time you restart the XDK, the COM link over the USB connection has to be reestablished, which takes some time. We can't change this behaviour and the duration of this process will variate as it depends on multiple systems. Since the flashed applications are started before this link is ready, printf's that are called in this startup time will be executed, but are not visible in the XDK-Workbench console. If you need the same timestamp offset every run, I'm afraid you have to find a workaround, like in your case the interrupt.
3. From the SDK you only receive a realtive timestamp, not an absolute time, that's right. But you could use NTP to receive the "real" time over the internet.

By the way, the workbench update works again.

I hope you get ahead with your project!

Kind regards,
Manuel
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