VL53L1X reading returns 0 with error code 31

[will3]

I am getting occasional readings from this sensor of zero(0) reading result with the error code 31.  According to the header file this error corresponds to:

#define VL53L1X_WARNING_OFFSET_CAL_MISSING_SAMPLES ((VL53L1X_Error) - 31)
/*!< Thrown if there is less than the requested number of
* valid samples. */

This is not during Calibration offset process,  which we do use,  but at run time after SetOffset using the stored offset value.  

Very confused why I would get this error,  occasionally,  at run time?

Thanks,

Will

[John E KVAM]

That is strange indeed. Something is happening somewhere as that bit combination is not in the hardware of the device. I found nothing in all the documentation I have that shows you can get a 31. 

So if the hardware is not throwing a 31, then you have to dig through the code to see what is going on. 

Sorry to leave you with homework, but I have no clues as to what could be going on. 

Perhaps you could add a check right after the range status is being read to see if you could trap something. 

-john

[will3]

The #define I show is taken from the vl53l1x.h file.  How is that not in the hardware at all? The header file is from ST. 

[will3]

The API I use to return the status is the same I use to return the reading:

VL53L1X_ERROR VL53L1X_GetResult(VL53L1X_Result_t *pResult)

Would this change your answer?

[will3]

Hi John,

One change to my original posting,  I miswrote what the sensor reading.  It is in fact 32256 not Zero. 

Does this tell you anything more? 

Thanks,

Will