With this circuit you can drive a unipolar stepper motor. It operates in full step mode. The AVR attiny2313 micro controller controls the pulses for the stepper motor. The pulses are amplified by the ULN2003 driver.

 

The driver accepts 5V inputs, the output for the driver is up to 30V so you can connect an stepper motor of up to 30V if you use an external power supply. With the two push switches you can drive the stepper motor CW or CC or control it with a microcontroller

Hardware

The hardware consist of the AT2313 microcontroller which drives the ULN2003 driver and two push buttons to control the direction.

     

Software

The software makes the pulses for the stepper motors. Two pushbuttons are used to move the motor left or right. The program code is made with the AVR BASCOM compiler. You can download it below.