I finished testing both applications with DS18B20 temperature sensor so both libraries, onewire and ds18b20 are working well with Low Layer API. And the compiled code is almost four times smaller. The applications are identical with the ones written for HAL API.

I prepared the library for the PCF8583 real clock timer that uses the I2C bus – the reason I moved to LL API – so I should be able to test it soon…

Not yet an update from STM for their CubeMX application (4.22.1 version) – functionality for generating LL code for a Makefile based application is still broken…