6v6gt:
Try adding external pullup resistors (say 4.7k) to the i2c connections so the lines are pulled up even if the rtc is missing.
Same result unfortunately. I'm using a MEGA board and the right pins (20 & 21). I guess that it has to be a code problem...but no solution comes to mind...
The thing is, if I use the I2C scanner code, it gets a response from the clock, even if I use the scanner in the program I'm running.