I am fairly new to the electronics scene, so I don't have the experience or knowledge yet to answer my questions and fix my problem.
I have an Arduino Uno R3 and I am trying to control a lot of inputs and outputs. I have three monetary switches as inputs, and I have 2 LEDs, an LCD, and a 180 degree servo motor that I am trying to use as outputs. After wiring all of the components to a solderless breadboard to what I thought and still think is the right set up, I typed out all of my code that I needed to give my circuit a test. When I went to plug in my Uno to my computer, I noticed that the mini LEDs on the arduino uno board would be lit for about a second but then immediately fade. My original thought was, "ok, the USB must not be providing enough power." So I hooked up a 9V battery and bridged my positives on each side of the bread board as well as the negatives on each side of my breadboard. When I plugged the USB back into my computer, everything flashed (including my computer screen) and my computer turned off. I'm pretty sure that I fried something on my board because I disconnected the 5V power wire and ground off the board so I can at least transfer my coding onto the board but now my computer will not recognize the serial port.
After Some research of the Arduino Forums, I have pretty much have accepted that I fried a component on my board and need a new one. Is this right to assume or is there a way to still use what I have?
also, if I do get another board, what board shall I get to make this not happen? (I was thinking the Mega). and How can I prevent this from happening again if the board capability itself is not the problem? (i.e. using more resistors, capacitors, diodes?)
Somewhere in your circuit you have a low resistance (short circuit) path from +5V to GND. The reason the power light faded out was a resettable fuse in line with the USB 5V to offer some protection - and it's fading out should have been an immediate red flag to say, hang on, something isn't right. Supplying more power isn't usually the best first step for debugging - not on a prototype of something anyway.
Double check all of your connections, use a multimeter if you have one to check for short circuits. Also you can use the multimeter to check for a short circuit in the arduino board (with nothing else connected!) before plugging the board back in to the computer - just to make sure that if something has fried you don't do any more damage to the PC.
I plugged my circuit back into my computer this time without the 9V battery and for some reason there fade problem is not happening. Maybe I had two wires touching and shorting the circuit.
KenTF:
Try working through this sequentially.
Find a usb mouse or memory card and plug it in that usb port. Does it still work?
If not find another usb port that does. (if you can)
Having found a USB port on your computer that actually still works
Now open the arduino ide (without any arduino attached to your computer)
Goto tools.. Serial port and take note of what ports are being reported.
Now plug your bare uno into the usb port (without anything connected to it).
Go back to tools.. Serial port. Has another port appeared?
If so, pick that one.
Let us know how it goes thus far.
I went through your steps and I still have the problem that my chip won't communicate with my computer. It still gets power through the USB but the IDE cannot detect the port.
Is the device detected at all? If not then you have probably blown the USB to serial chip in which case it would be very difficult to get the board going again. You could get a different USB to serial cable and programming with that though there is no guarantee that the atmega chip is not blown too.
Hi, can you post a copy of your circuit please.
A CAD or a picture of a hand drawn circuit in jpg, png or pdf format will help us a lot to see where your problem can be.
