Using I2C on ATMEGA328P-PU not working

spycatcher2k:
DON'T DO THAT! Post new info inline.

I am not sure how to upload a picture when doing the "Quick Reply" - so I just edited my original post.

Here is my reply (but please see the image I attached above):

I've uploaded the schematic. Some more details:

  • Blue wires are the SCL and SDA
  • Crystal clock is 16 MHz with two 22 pF caps to ground
  • Real Time Clock is "RTC DS1307" .. not exact as shown in schematic. However, as stated, I've tried this with other I2C components with similar bad results.
  • FTDI breakout is "FT232R Breakout" ... again it is not exactly as shown in schematic. The one I have is not available in Fritzing.
  • The capacitor to reset is 0.1 uF. I actually had lots of trouble with this. Without this cap, I couldn't upload sketches. But it was in this forum that I found the answer.

Lastly - I've tried this with and without the 10k Ohm pull up resistors. Similar results either way.