I have a problem with I2C connection between my PIC 18F4550 and Atmega 328p (Arduino Uno). In PIC I have 20Mhz XTAL and in Atmega also. I think that the problem is in Atmega(Slave), because when i run the program in PIC, the SDA and SCL works well ( i see this in oscilloscope). I´m using XC8 and I2C.h.