Possible issue with temperature readings

[rossb93]

I was testing my bean within a fridge and when the temperature fell to 0 it seems the reading overflows and hits 255 instead of showing a negative representation. This was done using the temp request function within bean.js just as was done in the examples.

[aguerrieri]

That's the expected behavior. getTemperature returns an int8_t, which is a signed 8-bit integer which can represent numbers from -127 to 128 (which suffices, considering the bean can report temperatures from -40C to 88C). The negative numbers are represented in the "upper half" of the 0-255 range, adding the negative number to 256. In other words, 255 is -1 (256 - 1), 254 is -2 (256 - 2), etc.