First, my apologies if this is in the wrong area this is my first post and seemed like the best area for it.
I'll try to make this as short as possible while still being as detailed as possible too.
So I am fairy new to Arduino's, microcontrollers and programming there of in general and while working with a pair of stepper motors for a little project I fried the chip on my UNO (literally set it on fire... Had about a 2 to 3 inch tall plasma like flame shoot out of the top of it) but I dont know how... I also couldn't back trace my wiring on my breadboard when I did it because my first reaction was to grab everything and yank it all out of everything.
Since everything looked good on the board other than the chip and the socket, I ordered a pair of new chips and sockets and thought that would fix it but apparently it did other damage too because after replacing the socket and putting in a new chip (yes, chips have the bootloader (I think thats the correct name) pre installed on them), nothing happens when I plug in the USB cable. It does power up but there is ZERO communication / computer doesn't recognize that anything was plugged into the USB Port. This I guess makes sense because when it fried initially, it actually crashed / shut down my laptop in the process (which luckily was undamaged)..
Anyways, I picked up a new UNO and went on with what I was originally trying to do with it and just made sure to quadruple check my wiring (no more problems and got everything to work as intended... (still boggled how I could have hooked anything up wrong to send 24v back into the board since all control wiring to the stepper drivers is opto-isolated but I cant think of anything else other than somehow sending 24v back into the chip.
Fast forward to yesterday / today. I started working on another little project using a Pololu motor controller to run a pair of Electric parking brake calipers. After getting it "sort of " working (still having a problem with coding one of the functions... but thats a different topic), I decided to pop the chip out of my working UNO and plug it into my one that had the problem above and plug in the motor shield just to see if it worked since it would power up, just not communicate via USB and to my surprise, it seems to work fine.
With that said, clearly the initial problem that caused to to catch fire also did something to another component that has something to do with the USB communication (which again, I guess makes sense since it crashed / forced my laptop to shut down when it caught on fire).
So my question is, does anyone else know if there is more that I could have fried that could cause basic functioning problems beyond the USB communication problem that might not show up right away?
I ask because although they are cheap, I was thinking about just using this one for the parking brake controller instead of buying another one since it appears to work fine.
Oh and although it probably doesn't matter but incase it does, this is a real / genuine Arduino UNO, not a clone / copy.