Arduino Uno onboard LED and power-on LED flashing, board not detected

Hi,

I was trying to implement a push-button program (similar to this: http://microcontrollerslab.com/use-push-button-arduino-uno-r3/) using my Arduino Uno and neglected to use a resistor between the +3.3V and analog input, which I think was a mistake (it’s been almost 10 years since my college E&M class…).

Now the board cannot be detected by the Arduino editor (both on a Macbook Pro and a PC running Windows 10), and when the board is only connected to a power supply, the onboard LED and the power-on-indicator LED both flash at a frequency of approx 1 Hz. The reset button doesn’t do anything, and I can’t do a software reset. Have I totally hosed the board? Does anyone have any suggestions on whether this can be recovered, or what the blinking of these two LED’s indicates?

The code is below and I’ve a photo of the board setup. (Pins 10+GND are just going to an oscilloscope; +3.3V, GND, and A1 are connecting to the breadboard.)

Thanks.

/*

*/
int buttonStatus; // Variable declare to store status of digitalWrite
 void setup() {

  pinMode(A1, INPUT); 
  pinMode(13, OUTPUT); // led
  pinMode(8, OUTPUT);  // other pin
 }

void loop()
 {

 buttonStatus = analogRead(A1);
  if (buttonStatus == HIGH) 
  { 
  digitalWrite(13, HIGH); // led
  digitalWrite(8, HIGH);  // other pin
  } 
  else 
  {

  digitalWrite(13, LOW); 
  digitalWrite(8, LOW);
  }
 }

tmandel0:
when the board is only connected to a power supply, the onboard LED and the power-on-indicator LED both flash at a frequency of approx 1 Hz./*

I have read that Arduinos (like the uno) have something called a polyfuse. The polyfuse, is supposed to protect the usb host from excessive current drawing. When you say power supply, do you mean usb computer?

Is the regulator hot?

Are driver correctly installed?

Thanks for the reply. When the Uno is not connected to a computer but to its own power supply, the LED's flash. When the Uno is connected by USB to a computer, but not to a separate power supply, both LED's stay illuminated.

I'm very new to using Arduinos so not entirely sure where the regulator is... the board itself has felt warm but not overly hot. I've left it to "cool" 24 hrs in case something was overheated (e.g. this thread: http://forum.arduino.cc/index.php?topic=303289.0), but still have the exact same problems.

I'm assuming the drivers are correctly installed, as the board interfaced fine previously.

How is the power supply?

And here's a Arduino uno regulator:

If link does not work: click here

Check in tools that the correct board and port is correct. Once, I was coding and the code would not upload correctly and I kept checking and checking looking through everything and it was just the wrong board!

OK, I'll have to check the regulator. What would that indicate if the regulator were running hot?

The selected board type is correct, but in the web editor (on Mac) the board is not detected, and in the IDE software (on PC) the "Port" selection menu is greyed out when the board is connected.

If the regulator is hot, turn it off, and make sure there are no short circuits, or anything that would be bad for batteries. (Shorting, wrong polarity?)

tmandel0:
but in the web editor (on Mac) the board is not detected

Web editor???

Arduino Create???

If yes, than is the Arduino Plugin is working correctly?

And try to upload the blink example sketch with windows or mac, ide or web editor, as long it runs.

Yes, Arduino Create. I'm not sure what you mean by the Arduino plugin?

For Mac/PC and web/IDE, the board is not detectable so I cannot upload any sketches.

Arduino Create: Go to here

IDE: What does the tools->boards menu say?

Sorry I added the wrong URL please refresh.

Fixed.

Thanks. I already have the Arduino plugin then. I've been able to successfully upload different sketches with this board previously, but since the push-button incident it is no longer detected and I'm getting the flashing LED's.

Try with a different Arduino...

tmandel0:
Hi,

I was trying to implement a push-button program (similar to this: Push Button Interfacing with Arduino - Reading Digital Inputs) using my Arduino Uno and neglected to use a resistor between the +3.3V and analog input, which I think was a mistake (it's been almost 10 years since my college E&M class...).

Draw and post a diagram on how you "broke your Arduino".

And, if you don't mind, post a picture of how your arduino looks.

Without knowing how it was connected, we can't venture a guess at HOW you damaged it.

Does the board detect at all? As in, do you get a serial port when you connect it? If not, and it worked previously with the same computer and a known good cable (there is a plague of bad cables going around - I think someone is selling arduino starter kits with low quality USB cables), you've trashed the serial adapter. Throw the board out and buy a new one.

The official boards (and faithful clones, ie, ones with the 16u2 as serial adapter) seem very easy to damage if you abuse the power rails - much harder to damage the cheap clones with ch340g or cp2102 serial adapter.

OK, thank you both for your replies. My question was not how I damaged the board, but whether anyone else had experienced this blinking of both the pin-13 LED and the power-on LED, whether this was some recognizable and diagnosable error, and whether it was something that I could fix on my own.

In my first post, I attached a .jpg of the board and I’ve re-attached it here. (And for anyone else’s future reference — add a resistor to the push-button setup!)

DrAzzy, the board does not detect at all. Guess I’ll use a new board and a resistor now.

Sorry I did not see the picture.

Yep. Your arduino has been shorted a most likely it is dead.

Sorry I am typing on a phone messy a lot.