A stepper motor (or step motor) is a brushless synchronous electric motor that can divide a full rotation into a large number of steps.
The motor's position can be controlled precisely without any feedback mechanism, as long as the motor is carefully sized to the application.
Stepper motors are similar to switched reluctance motor (which are very large stepping motors with a reduced pole count, and generally are closed-loop
The stepper motor can be interfaced with the 8051 using l293d connected to p1.0,p1.2,p1.3,p1.4
Stepper motor two types of step sequence 1) full step and 2) half step sequence
In the full step sequence, two coils are energized at the same time and motor shaft rotates. The order in which coils has to be energized is given in the table below
WHAT IS STEPPER MOTOR ?
Full step and half step sequence In the full step sequence, two coils are energized at the same time and motor shaft rotates. The order in which coils has to be energized is given in the table below. In Half mode step sequence, motor step angle reduces to half the angle in full mode. So the angualar resolution is also increased i.e. it becomes double the angular resolution in full mode. Also in half mode sequence the number of steps gets doubled as that of full mode. Half mode is usually preffered over full mode. Table below shows the pattern of energizing the coils.