RAK1906 BME680 - Does this look familiar to anyone?

Using the ClosedCube library in the simplest possible way… gas = bme680.readGasResistance();… every time the gas resistance value exceeds about 560K it drops to about 90K until the value falls back below that 560K value, like this…

Does this pattern (the gold-colored trace) look familiar to anyone? A library issue, maybe, or possibly I’m doing something wrong?



Looks like it could be an integer overflow type of issue, the question would be, precisely where.

If you can create a serial log of values at each level, eg, raw read from teh sensor, processing, transmission, decoding, etc you may be able to figure out where the problem is.

It does, although 565K doesn’t ring a bell as a common overflow point. Anyway, I’m looking directly at the values coming out of ClosedCube. So I’m wondering particularly if ClosedCube users have seen this behavior.

If you look at the open and closed issues and pull requests in the closed cube repo there seems to be a history of bugs of this nature, some apparently fixed some maybe not

Yes, there seems to be an open issue there. So as an alternative, anyone have anything good to say for any of the other BME680 libraries out there?

I am using Zanduino’s BME680 library, but I did not use the gas resistance, because the heater process makes the temperature and humidity sensor values unusable.