No LED activity or usb serial connection

Using Arduino Installation & Troubleshooting
#1

I just bought a new Arduino UNO R3 from Radioshack yesterday, whne I plug it in to either of my computer there is no LED activity on the board and it does not create a /dev/ttyUSB* or /dev/ttyACMO* on my (linux) system. In my googling I have learned that the Arduino is suppoed to light up when simply plugged in, but mine does not even do that. I have tried 2 USB cables so far, but no luck.

This is the output of dmesg|tail before I plug it in:

[ 2217.032117] usb 3-1: device descriptor read/64, error -71
[ 2217.260108] usb 3-1: device descriptor read/64, error -71
[ 2217.476097] usb 3-1: new low-speed USB device number 31 using uhci_hcd
[ 2217.600051] usb 3-1: device descriptor read/64, error -71
[ 2217.824097] usb 3-1: device descriptor read/64, error -71
[ 2218.096120] usb 3-1: new low-speed USB device number 32 using uhci_hcd
[ 2218.508033] usb 3-1: device not accepting address 32, error -71
[ 2218.620071] usb 3-1: new low-speed USB device number 33 using uhci_hcd
[ 2219.032060] usb 3-1: device not accepting address 33, error -71
[ 2219.032075] hub 3-0:1.0: unable to enumerate USB device on port 1

This is the result of dmesg|tail after I plug it in:

[ 2751.648065] usb 3-1: device descriptor read/64, error -71
[ 2751.872102] usb 3-1: device descriptor read/64, error -71
[ 2752.088086] usb 3-1: new low-speed USB device number 35 using uhci_hcd
[ 2752.212074] usb 3-1: device descriptor read/64, error -71
[ 2752.436102] usb 3-1: device descriptor read/64, error -71
[ 2752.652075] usb 3-1: new low-speed USB device number 36 using uhci_hcd
[ 2753.068060] usb 3-1: device not accepting address 36, error -71
[ 2753.180120] usb 3-1: new low-speed USB device number 37 using uhci_hcd
[ 2753.596069] usb 3-1: device not accepting address 37, error -71
[ 2753.596087] hub 3-0:1.0: unable to enumerate USB device on port 1
#2

If it isn't powering up and it isn't getting enumerated then it can only be:

  1. The board is damaged.
  2. The cable(s) being used are bad.
  3. The USB port of the PC isn't providing power.
#3

Is it possible to fix whatever is damaged myself? Or do I need to return it?

#4

I just tried using an external power supply, the 'ON' and 'L' LED's are now on, but the unit still can't enumerate.

#5

I was using a 3-12v 2A power supply, at 12v some smoke was emitted from the regulator, I immediately unplugged the arduino, it looks fine and doesn't have any less function than before.I have noticed that the 'L' LED turns OFF when the USB cable is plugged into the computer, I don't know if that is supposed to happen or if the computer USB ports are somehow drawing current from the arduino.

#6

If you bought it from RadioShack then don't waste you time, just go back and exchange it.

#7

When plugged into a 9v 500mA supply, the ATMEGA chip became too hot to touch, is this normal?

#8

hiduino:
I you bought it from RadioShack then don't waste you time, just go back and exchange it.

I be able to get over there in a couple of hours, I think I'll do that, but I would still like to find out what the exact problem is. :~

#9

Sounds like something is shorted on the board.

Without poking around with a multimeter or physical inspection it would be difficult to determine what.

#10