I used a usb to computer to begin with for power, then I used an external power supply of 12v/1amp and it wasn't doing anything. Then I unplugged and switched the wires from the 5v on the Arduino to pin 9 on my ULN2004A, and left Vin attached to the 50k trimpot and Unipolar 2-phase stepper(4vdc, 1.2A/phase) Com A and Com B. I heard a pop when I plugged it in, and immediately unplugged it; smelling burnt chips. It will still operate the stepper, but unrecognized by my computer.
My question is, can I replace my AtMega328 and get programming again, and what was the moronic decision I made that fried my Arduino?
Thanks guys! XD