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[on:]

I have been playing about with my arduino since december (a fantastic xmas present) but just recently I bought some new electronics parts (a breadboard and some jumper wires) eager to build bigger ciruits but wanting to check everything worked first I set up the new bread board and completed a basic pin 13-breadboard-resistor-led-ground circuit.

It didn't work, assuming my understanding of the bread board was wrong i tried to form the circuit down a column (instead of across a row) which didn't work either. I then assumed my breadboard was bad and tried the new wires with an old bread board I know works. Nothing happened.

After a series of experiments it turns out the only thing my arduino can do right now is light up an led on pin 13 directly plugged into the arduino. Even if i write the code to make it blink, the led will not turn off. To further assume I was in the wrong I uploaded the blink tutorial code direct from the ide and still the led would not turn off.

Can someone help me restore my arduinos functionality as I very much enjoy developing with my arduino and would like to continue to do so.

Thanks.

[Reply #1 on:]

Is pin 13 the only one that fails to work correctly? It is possible that you fried that pin, and a new chip is in your future.

[Reply #2 on:]

Nope, 13 is the only one that I can determine that does anything.

Changed the blink example to use pin 12 and nothing appears to be happening. I have managed however to make the blink example work on pin 13 if the led is plugged directly into pin 13 and ground. I had to use virtualbox with windows in a virtual machine with the latest arduino software but its some small progress.

However I am still unable to use breadboards or wires.

Its an arduino Uno.

[Reply #3 on:]

make the blink example work on pin 13 if the led is plugged directly into pin 13 and ground.

Don't do that you will fry the arduino. You NEED a resistor, if it didn't work with one you have either wired it up wrong or have too high a value, you should use something between 200 ohm to 800 ohm.

Does the software say the download of the sketch was successful? If so then most of it is working.

[Reply #4 on:]

You should always put a resistor between the LED and ground, ALTHOUGH the arduino does not source enough current to fry an LED (I read this on the tutorials from the playground, but I wouldn't do it myself). Sounds to me that you might be using a resistor value that is too high so that the LED can not get enough current through it to light up enough for you to see it. Again, a cheap logic probe or multimeter would save you a lot of time now since you could just check the outputs on the arduino PINS with it and see whats going on.

try a smaller resistor as Grumpy_Mike suggested.
HTH

-Igor

[Reply #5 on:]

I can confirm I have been using 100 ohm resistors for my projects thus far. I used those as its what came with a bundled kit. I have switched to 220 ohm (I believe) and I have as yet had no luck.

Sketches are uploaded correctly so I assume most of the board is working correctly, just not with this.

I am truly stuck now, I am also very curious as to why all of a sudden the board has stopped working since it worked fine until I unplugged it and didn't use it this weekend (of course it didn't do it to itself, I am just perplexed as to what caused it to appear to run fine then just not upon the next start up).

[Reply #6 on:]

100 ohms is enough to not blow the pins.
Can you describe what the internel pin 13 LED does with the basic blink program?

[Reply #7 on:]

When I launch the ide from a windows machine (which is the latest version) the internal led blinks correctly. I am stuck using the 21 revision of the software under linux because I am using a 64 bit os.

[Reply #8 on:]

When I launch the ide from a windows machine (which is the latest version) the internal led blinks correctly. I am stuck using the 21 revision of the software under linux because I am using a 64 bit os.

Which internal LED?  There are 4 LEDs on the board, the one marked L is the pin 13 one.  If that blinks pin13 works.

Have you remembered pinMode (pin, OUTPUT) in your investigations?

[Reply #9 on:]

If the internal or included led ("L") is working then you may have some wiring problem. Post a hi-res picture. Did you switch the positive and the negative of the LED?

[Reply #10 on:]

I can comfirm the L led blinks correctly.

I also do not have a hi res camera but I have taken what I can. I believe that I have gotten the LED the right way around.







I can clarify anything if needed.

[Reply #11 on:]

Hi,
The LED needs to be mounted 'horizontally' in your pic.
The rows of 5 on the breadboard are in fact wires with 5 connection points, so you've just connected both pins of the LED together.

[Reply #12 on:]

Well that was suitably embarassing....

Thanks for your help and sorry for the evident misunderstanding of electronics.

[Reply #13 on:]

The breadboard connections are:



HTH
-Igor