The provided driver has built-in maximum values such that if the sensor reports above 100% or 102.4% (depending on precision setting), the maximum value is reported, rather than what the ADC is reading. However, given the stated accuracy from the data sheet, its possible to be in a state where the BME280 functions correctly, and still reports that value. That is, 99.4% relative humidity, +/- 3% humidity, includes 102.4% Are those limits built into the hardware? I removed the min/max values from the driver to see if I could characterize the accuracy in the top 5% of the sensor's stated range. However, the readings still maxed out at 102.4%. If that limit is built into the hardware, the range should more correctly be stated as (accuracy at min) to (100 - accuracy at max).
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