Hi, Steve-Tee, I don't know what are you talking about. I use the 16F84 version in this thread. Like I said RB7 till RB5 is pulsing but RB4 never pulsing that why someone here say his stepper just humming. I debug it using TurboCNC 1Hz function. I don't believe some short of software simulation. Who is here that has tried it on real hardware?? No one i believe.