Kinetis Microcontrollers中的主题 Re: FRDM-K64F Accelerometer Configuration

FRDM-K64F Accelerometer Configuration

kylecote — Mon, 16 Mar 2015 20:21:34 GMT

Hello,

I'm working with the FRDM-K64F board's accelerometer to log data to an SD card for a project.

Working with the data we're noticing that it seems to be hitting the bounds of +-2g which is a configuration of of the accelerometer on board (FXOS8700CQ) but I wanted to confirm that the K64F's accelerometer is configured by default to +-2g as I couldn't find anything in relation to it in the the documentation for the board. If this is is the case the FXOS8700CQ should be reconfigurable to the other ranges of +-4 & 8 g and I was wondering how I would go about modifying the configuration within my project to make the change to allow for these ranges. Any advice is helpful!

Cheers,

Kyle

Re: FRDM-K64F Accelerometer Configuration

Rick_Li — Tue, 17 Mar 2015 05:04:04 GMT

Hi Kyle Cote,

On page 49 of datasheet of fxos8700cq, you will see the accelerometer full scale range can be selected by bit fs[1:0].

when selecting [0:0], the range would be 0.244mg/LSB * 2^14(LSB) = 4g, that is the full range is +_2g.

when selecting [0:1], the full range will be +_4g.

and [1:0] corresponding the rull range of +_8g

the datasheet is available at:

http://cache.freescale.com/files/sensors/doc/data_sheet/FXOS8700CQ.pdf?pspll=1

for communication, please refer to chapter 5.

hope it helps!

Re: FRDM-K64F Accelerometer Configuration

kylecote — Tue, 17 Mar 2015 06:50:41 GMT

Thanks for the input and help! I'll take a look at this tomorrow!