Example FXOS8700CQ Driver Code in Datasheet gives 0,0,256 for magnetometer x,y,z values

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Example FXOS8700CQ Driver Code in Datasheet gives 0,0,256 for magnetometer x,y,z values

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peter_macleod_t
Contributor I

The FXOS8700 is connected to Beaglebone Black via i2c.    The example code from the Datasheet is copied - print statements were added.   The accelerometer data seems fine but the magnetometer data is consistently 0,0,256.

The magnetometer control register 2,  FXOS8700CQ_M_CTRL_REG2, is being set to 0x20 for a burst read but it does not seem to work.

Not sure if this is being posted in the correct location....#

Peter

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TomasVaverka
NXP TechSupport
NXP TechSupport

Hi Peter,

First off, please double check if m_hms[1:0] = 0b11 (hybrid mode). 

Then I would recommend to check what is going on the bus using an oscilloscope or a logic analyzer. I have used a burst read in my example without any problems.

Best regards,

Tomas 

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