my circuit

hi everyone
i am a beginner of microcontrollers and this is my first project.i made a circuit of a navigating robot.i am attaching the circuit below.please correct if there are any mistakes and do tell me whether its gonna work or nor.if not why?
The 1st motor is a stepper motor used for the linear motion of robot and the second is a micro stepping motor used for the rotation of direction
this is connect to the PC by serial port and the signals from serial port are used for controlling the robot

Hi,
i haven't work with 8051 but You will have to use a MAX232 level converter because the serial port on the pc uses +12V/-12V and a 8051 uses 5V/0V

The LT1130 is an RS232 level converter.

according to what i know LT1130 converts the 12v DC to 5 v.so there is no use of max232. i just need whether the 2 stepper motors are connected properly and will there be any problem to manage two motors with same microcontroller