how to read BME280 sensor data using i2c2 protocol on stm32 blue phill? what should be replaced in the library?
This is the Arduino forum.
Which Arduino board is using the STM32?
Shouldn't you ask STM32 question on an STM32 forum?
Please note that this board's nickname is "blue pill" not "blue phill". There is (or was) a similar board nicknamed "red pill". The names are a reference to the movie "The Matrix".
Also, there is no such thing as "i2c2 protocol". The protocol is i2c. The STM32 chip on blue pill has two i2c interfaces called i2c1 and i2c2.
Why do you want to use i2c2?
Most bme280 modules have a pin or solder pads which allow selection of two different addresses. This allows 2 X bme280 connected to i2c1, which is the default interface that most libraries will work with without alteration.