i.MX ProcessorsのトピックRe: Working with iMX6UL-EVK I2C Accelerometer/Magnetometer

Working with iMX6UL-EVK I2C Accelerometer/Magnetometer

arnaudne — Sat, 30 Apr 2016 20:50:59 GMT

Hi everyone,

I'm a bit of a noob in Embedded Linux development. I just got an iMX6UL Evaluation Kit and succeeded to build a working Yocto Project image (core-image-minimal based, with some development packages added, as evtest).

I would like to retrieve (from an user-space console for the moment) events from the FXLS8471 Accelerometer and MAG3110 Magnetometer I2C devices already populated and configured (I looked in the imx6ulevk device tree).

I then launched evtest where I could see that /dev/input/event2 and /dev/input/event3 refer respectively to the accelerometer and magnetometer, but they return no event when I read them.

I suppose that we should configure them to provide interrupts at a fixed rate, but I could not figure where I should be looking.

Could someone help me with this ?

Thanks a lot in advance.

Arnaud N. (France)

Re: Working with iMX6UL-EVK I2C Accelerometer/Magnetometer

igorpadykov — Sun, 01 May 2016 01:05:02 GMT

Hi Arnaud

for sensor test one can look at unit tests :

imx-test package ../mxc_sensor_test/acctest.c

http://patches.openembedded.org/patch/103551/

https://support.bluetechnix.at/wiki/Linux_Software_User_Manual_%28i.MX6%29#Magnetometer_.28Freescale_MAG3110_module.29

Best regards

igor

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Re: Working with iMX6UL-EVK I2C Accelerometer/Magnetometer

arnaudne — Sun, 01 May 2016 20:13:20 GMT

Hi Igor,

Thanks to your answer, I managed to get the magnetometer working. Still seeking to enable the accelerometer input.

For the magnetometer, I used :

echo 1 > /sys/devices/virtual/input/input3/enable

Then I could watch for events with :

evtest /dev/input/event3

But "/sys/devices/virtual/input/input2/enable" does not exist for Accelerometer... I will find another way to get it working !

Thanks again

Arnaud.