A0 - V_BATPIN: after the resistor divisor we should get [0V;5V]->[0;1023] on analogue V_BATPIN with R1=33k and R2=51k, i.e. (+12v)51k(A0 pin)33k(GND)
A2 - BUZZERPIN
I2C:

A4 - SDA
A5 - SCL
RC control:

D2 - CPPM (PPM_SUM)
Motor driver pins:

D5 - STEP1 (PORTD 5)
D6 - STEP2 (PORTD 6)
D7 - DIR1 (PORTD 7)
D8 - DIR2 (PORTB 0)
D4 - ENABLE (for both)
If you look to the tail of the robot:

right motor = STEP1 & DIR1
left motor = STEP2 & DIR2
Also see for new defines added with this project for robot setup:

#define CURRENT_AXIS PITCH // possible to choose ROLL or PITCH axis as current.

//#define INVERT_CURRENT_AXIS // invert current axis sign, i.e. instead of turning sensor board

//#define REVERSE_MOTORS_DIRECTION // reverse both motors direction

#define MAX_SPEED 400 // should be <= 500 #define MAX_TARGET_ANGLE 120 // where 10 = 1 degree, should be <= 15 degree (i.e. <= 150) #define MAX_STEERING 90 // should be <= 100

//#define GY_521_INVERTED_BY_Z // Chinese 6 DOF with MPU6050, LLC, inverted/reversed by Z