please very fast

(%25) Assume that you are required to control a stepper motor with 10 of stepping angle connected to lower 4 bits of Data Port of a standard parallel port. When you press 'u' from the keyboard the motor speeds up by 100 rpm at a time. Similarly, if you press 'd' from the keyboard the motor slows down by 100 rpm at a time. The speed changes between 0 rpm and 500 rpm. Speeding up higher than 500 rpm and slowing down from 0 rpm is not allowed. Write an assembly language program to control the speed of the stepper motor. Furthermore, the program displays the current speed at the center of the screen