Stepper motor driver code

Somebody please give me code for the driver used for stepper motor.

i need slow acceleration from low to high so that stepper will attain higher rpm.

The AccelStepper library uses acceleration for stepper movements. Lots of example code with the library.

Usually the ramp up/down speed is controlled with a loop. So you would have a delay that is set as a variable in the loop that slowly increases on decreases. For example, the delay between steps might start at 100 milliseconds and each time through the loop you decrease the delay for 5 milliseconds until you achieve the speed you want.