So I have an Arduino Nano ATMega328 that I'm trying to upload a program to, but my board is not appearing in my devices when I plug it into my computer. I was able to do so perfectly fine last week, but I have since soldered the board to a PCB. When I plug it into the USB port, the TX, RX, and PWR lights on the board light up, but the computer does not recognize that a board has been plugged in. Several of the LEDs run off the Arduino also light up from whatever program I had last uploaded to my board. I'm running Windows 7, 64-bit. I've tried a different USB cable, a different USB port, a different computer, and a different board. My Uno works fine, but the Nano just won't show up. Could I have damaged the board when I soldered to it? Or could it be that something in my circuit is causing it to not communicate with the computer? There is a MAX3323 in my circuit. I'm not really sure how to troubleshoot this problem and I need to figure this out fast.
I thought it might be related to the fact that the TX and RX lights on the Arduino are lighting up, but I'm not sure. The board is not receiving or transmitting any information to the computer...
Also it's a pretty complicated circuit, so a picture wouldn't be enough to tell if something is wrong.
LeslieM:
Also it's a pretty complicated circuit, so a picture wouldn't be enough to tell if something is wrong.
No but a schematic (even a rough one) might help to explain to others what your circuit looks like. The question really was, where is this additional chip connected and how?
Without it, we are stuck to saying:
Yes you could have damaged during soldering.
Yes, it could be something in your circuit.
The more information--specific information you give, the better the help you get.