Stepper Motor Controller
This is a PIC based Stepper Motor Controller.There is a lot of online literature about stepper motors and controlling them. A Google search turned up the circuit below. It uses a PIC microcontroller to sequence the steps, TIP120 Darlington pairs for the switching circuitry, and a cd4050 hex buffer for logic levels and circuit protection.
   Stepper Motor Controller with PIC16F84
More detail on Stepper Motor Controller with PIC16F84 website
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