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Question asked by maximus on Sep 15, 2012
Latest reply on Sep 20, 2012 by Kevin.G
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Dear Analog,

I recently ordered an eval board EVAL-ADXL346-DB. I have a couple of questions:

1) I am able to read the data out in x,y and z axis. But however this data seems like decimated data. How do I read the undecimated data out of the x,y and z registers ? because that is the actual data that is compared against the single-tap , double-tap and activity thresholds . It is very important for us to read that data.

2) I used the ARMWSD tool to load the different .hex files on the eval board using the serial cable. However it does not allow a finer control over the register settings. For example if i have to change the power modes (low power to high power) I cannot do so (i know i can use 800Hz ) but i just want to be sure that i can set those bits. Also wanted to experiment with other bits in the register. So my question is : Is there a way to program the registers in the ADXL 346 eval board using just the tools(serial cable)provided in the box ( without having to connect it to a special hw )

3) We ordered this part from digi-key and the on-off switch is very shaky. When i put this in on position , the green light does not glow until I manually adjust it by pushing is slightly on either side( Initially I make sure that I have pushed the button to the proper on position ) . Is this common behavior on eval boards or we just got a faulty one ?

4) The Excel file (data plotter) that we use only plots y axis data and hangs for a while. Then it throws an exception . I am not too concerned  with this bug but would be nice if i can get an improved one. Attaching the file for reference.

Adding a few more :

5) ) Is there an internal sampling rate that ADXL uses which is different from the sampling rate specified by the user in the BW register ? If yes what is it?

6) How different is the undecimated data vs the decimated data in terms of noise, when operating in Low Power Mode? Does the ADXL give decimated data in the x,y and z registers ? Is there a way to read the undecimated data from the ADXL ?

It would help if someone can answer this questions on priority as it will unblock us.