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sparkfun / SparkFun_MLX90640_Arduino_Example

Controlling and reading from the MLX90640 IR array thermal imaging sensor
https://www.sparkfun.com/
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NaN result for specific pixel #16

Closed vishalkothari closed 5 years ago

vishalkothari commented 5 years ago

Hi,

I am running Example2_OutputToProcessing. I am facing a problem that Pixel 22 always has value NaN. All other pixel values seem to be ok. I traced this further and found that irData calculated in MLX90640_API.cpp > MLX90640_CalculateTo() has a large negative value like -6874.43 for Pixel 22. irData for other pixels is in -10 to -20 range.

I have tested this with Teensy 3.5 and ESP32, I see the same issue with both. Has anyone faced similar issue?

LBuydens commented 5 years ago

Hi,

the MLX90640 can have up to 4 dead pixels. These should be indicated in the EEPROM table. I expect that in your sensor, pixel 22 is malfunctioning. Depending on your application you can ignore that pixel or replace it by the median temperature value of the surrounding pxiels.

vishalkothari commented 5 years ago

Thanks @LBuydens .