Fast Clock can be easily activated without complicated adjustments in config.h:
Serial:
simply comment out the required port: e.g. #define SERIAL1_COMMANDS
OR
for I2C
//#define FAST_CLOCK_I2C 0x55
and define the address
serial is working
I2C is wrong
First, the initialization was incorrect. The FastClock was initialized before the I2C Manager was initialized
Second: FastClock Functions are missing