I am working on simulating a BME280 sensor in software, I have figured out values to pass in for the dig_T* values so that the compensation formulas just pass through what I send as my raw data over I2C, however I have been unable to work out values for the dig_P* values or the dig_H* values so that I can consistently send a value that will be translated to what I want at the end. If there are any defualt values or some values that will result in scaled versions of my raw data that would be greatly appreciated.
BME280 dig_T*, dig_P*, and dig_H* registers are trimming coefficients unique to each part. Therefore the best thing you could do is to copy 1 set of values from a sensor to simulate the output of that specific sensor.
Maybe what you are looking for is simply the API to read uncompensated data ?
First you can grab the raw data directly from the bus with this API: