I'm familiar a bit with i2c but I'm not sure why I do not see data. I want to communicate with a thing called the wii-mote. It uses i2c to talk to its peripherals. I'm trying to emulate a peripheral with an atmega32u4. From what I have read the master should init the communication and I should see a low clock followed by a low SDA. I tried using the chip to pull up on the two lines and after no luck there I used a pair of 4k7 pullups to 5v. Both lines high is a free bus I was pretty sure. Watching the actual device and its peripheral I see the communication start. When I plug in my emulated peripheral I do not see any activity. I'm wondering if the master is waiting for something before it begins? If so what could it be waiting for? Based on what I have gathered on the net I should see the master attempting to talk even if there is no peripheral but I most certainly do not see that.
I also have read the 3 to 5 TTL can be fussy so I put things on the scope and the two pullups are holding at 2.7. Maybe this is my issue but most designed do not even use pull ups.