Stepper motor control using the PIC16F684 application note (PDF!) from Microchip:
This application note describes how to drive a bipolar stepping motor with the PIC16F684. The Enhanced Capture Compare PWM (ECCP) module is used to implement a microstepping technique known as hightorque microstepping. The microcontroller’s 8 MHz internal oscillator allows the signals generated by the ECCP module to achieve frequencies above the audible range.
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