Positive supply voltage. This can be either a 3.3V or 5V source
The direction pin is used to set the direction of positive rotation. R3 pulls this pin high to set the clockwise as the default positive direction
I2C clock line. R1 pull this pin high.
I2C data line. R2 pulls this pin high.
Program option (internal pull-up, connected to GND = Programming Option B)