This page is about interfacing a stepper motor to a MICROCHIP “PIC16F84-04/P”. I found that interfacing and controlling the stepper motor was quite easy by using ALLEGRO Microsystems UDN2916 stepper motor driver IC. The biggest thing to remember when interfacing the stepper motor to the MCU is the timing between steps. If you go too fast the motor will not step. If you go too slow the motor will not step smoothly. I wanted to get the motor to go as fast as I could with as much torque as possible, but I wanted it to be smooth. Using the UDN2916 made this task very easy. The stepper motor driver IC I was using is a Dual Full-Bridge PWM IC that can deliver up to 750mA max with a max motor voltage of 45VDC. If you are going to run this circuit for any length of time greater than a few minutes at max current, make sure you heat sink the motor driver (trust me it gets warm!). As always, a big thanks goes to everybody on the PICList who answered my questions and helped me out. THANKS!!
See the schematic here!! Motor Project Schematic
Download the assembly (.asm) file here: mckt_tst.asm