TWI Wire.setClock() on non arduino AVR MCU issue
Looking to get 100 kHz clock. What am I missing?


Calculations are int (16-bits) by default in AVR GCC. Try 100*1000L. Or even better:

#define F_TWI 100000L 


and use: 

TWBR = ((F_CPU/F_TWI)-16)/2;


or:

Wire.setClock(F_TWI);


Cheers!