Not sure if it was posted already, but these are the pins I identified for the mBot, as compared to an Arduino UNO:
A0 RJ25 plug 4 (default not-connected)
A1 RJ25 plug 4 (default not-connected)
A2 RJ25 plug 3 ultrasonic
A3 RJ25 plug 3 ultrasonic
A6 light sensor
A7 button
D2 IR RCV
D3 IR TX
D4 DIR2 - direction motor2
D5 PWM2 - pwm motor2
D6 PWM1 - pwn motor1
D7 DIR1 - direction motor1
D8 buzzer
D9 RJ25 plug 2 linefollower
D10 RJ25 plug 2 linefollower
D11 RJ25 plug 1 (default not-connected)
D12 RJ25 plug 1 (default not-connected)
D13 2 WS2812 RGB leds