ArduPilot Legacy (Atmega328)

Hi,

I've connected the 4th pin to the SDA, 5th pin to the SCL, Ground to the ArduPilot ground, and Vcc (because I was lacking options) to the 6th PWM pin (in which I've set it at 3.3Volts in the IDE).

Today, I decided that would be a better decision to use a voltage regulator. Surprisingly I have a LM317. I've made all the connections and now the voltage regulator powers up the I2C sensor while the input is being send to the Ardupilot. It works.

Now, even if I got here, what was the original problem with that pin? (It was set at 165 in the Arduino)

Thank you,
RobertEagle