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With the bme68x.h sensor API, the gas resistance value occasionally saturates to 102400000.0 and this doesn't seem correct. This really only happens for lower temperatures in the heater profile (say 100C, as opposed to 150C or above) I ran some debugging and here's what I know: The gas resistance value is calculated using two inputs, gas_res_adc and gas_range. The calculation is 102400000.0 when both of these inputs are 0. (They shouldn't ever be 0). These values come from registers gas_adc and gas_range, at addresses x2C and x2D. It appears that often times when I read these registers, they store 0. This is the case even when the status bits BME68X_NEW_DATA_MSK, BME68X_GASM_VALID_MSK, BME68X_HEAT_STAB_MSK are TRUE. So it seems that the gas_adc and gas_range registers often hold no data even when the status bits indicate that there should be data there. This only happens for lower temperatures of the gas heater profile. I cannot figure out why this could be. Anyone seen this before? I am not using BSEC or the Development Kit, I am just using the source code API from GitHub: https://github.com/BoschSensortec/BME68x-Sensor-API/blob/master/bme68x.h ... View more

We're looking to use the bme68x sensor to detect different gases such as coffee, smoke, fresh air, etc. So, we're looking for the right gas heater profile(s) to use, and we don't have much intuition on how to come up with them on our own. Any tips or resources on choosing heater profiles? Is the default heater profile from the datasheet the best place to start? If that doesn't work, what do you recommend next? Is it also recommended to use multiple heater profiels for detecting different gases? Or is there a one-size-fits-all? ... View more