SEN0390 firmware and/or schematic

Hi!

Is there schematic and/or firmware for HC32L110 (the chip onboard the sensor board) available for that module? The I2C implementation for this sensor is terrible and I reckon I could probably figure out better way to communicate with it, but there's no info on what is the light sensing part of it, nor how does it apply any calibration etc.

Other module manufacturers share those, but for some reason DFRobot doesn't seem to share anything on their wiki apart from broken piece of library that doesn't work well. From what I found so far it's trying to mimick I2C, but bits are off. Maybe it could be done better? HC32F110 has proper I2C hardware.