A Step motor (stepping or stepper motor) is a digital motor. The digital signal is a square wave signal. The step motor responds by rotating its axis a certain number of degrees as the digital signal. A controller programming of a half-step operation of the step motor and a counter of the number steps use a MCS-51 experiment broad to display the results, and an Atmel’s AT89C51 stores and executes the instructions. The Atmel’s AT89C51 has the 128-byte internal static random access memory (SRAM) and 4-KB flash memory. When the instructions are recorded in the AT89C51, this device can control the step motor in half steps by using the MCS-51. For the number of steps counting is limited by display on the MCS-51. This broad has only two 7-segment display. The number of steps can be calculated the rotational angles.