Arduino Duemilanove - L led

What does the L led mean on the arduino board? I assume it means load as it lit up while i was poking at a motor with it on the 5v power out.

I don’t know what the “L” stands for, but that LED is connected to digital pin 13 (through a resistor). It lights when pin 13 is high. That makes an Arduino board more useful without needing to have more components attached.

Oh, that’s right… i totally forgot about that (i kinda… sat this down for a month or two and have gone dumb on it…)… i wasn’t 100% sure whether it was the L or rx/tx lights, but am afraid to put the motor against it in fear that it will burn out the atmega chip.

The L just stands for LED from what I know… what do you mean it

“lit up while i was poking at a motor with it on the 5v power out”?

port 13 has an internal resistance so you can connect a led to it. It depends on what motor you want to use…

port 13 has an internal resistance so you can connect a led to it.

No it depends on what type of arduino you have. Most do not have the output connected through the resistor so you can’t connect a LED directly to it.

poking at a motor with it on the 5v power out

A very good way of damaging your Arduino.

Lol… Umm… well, just as i said, i was impatiently poking at a stepper motor with the 5v out and ground seeing if the motor would respond to the 5v pin that was available, and the motor spun up and locked into place without problems and appeared functional. When it did, a light lit up and i was like “crap! did I burn it out?”. It may have just been the rx or tx for some reason.

It’s still working fine, I just wanted to make sure I hadn’t damaged something, but so far, it appears to be functional… My dad works pretty extensively with the Pic boards and suggested I could burn it out pretty easily if it’s anything like his boards, but I believe these are a bit more dummy proof.

@grumpy mike: I dont argue that… Like I said, my dad works with pic boards and immediately insisted I buy like 5 atmega386 chips and an image burner board as he knew my personality on that stuff… I never claimed it wasn’t a dumb move. :wink:

I believe these are a bit more dummy proof.

I wouldn’t count on that. Unless you mean that when it burns out, it’s proof you were a dummy.

Unless you mean that when it burns out, it’s proof you were a dummy.

Lmao! ;D

In my modest defense, it was moderately educated random poking? Does that help me boost status? No? Man…

The motor runs very happily at 1.5v so I figured that the worst that would happen was my motor (that I found in an old hard drive) would overheat and be done for.

I mean, could someone educate me on this? If I were to plug 5v directly into ground on my arduino duemilanove, it wouldn’t burn it out, would it? From my understanding the 5v could happily hang out plugged into ground on that same side all day if it wanted to. Is that correct?

Does plugging a motor between that pull more amperage and potentially cause damage?

I still have a poor understanding of amperage/wattage/voltage outside of their definition. Is there a way to calculate the wattage or amperage? I have a basic voltmeter to test voltages. Is there another tool I should get? (aside from the expensive oscilliscope that I will inevitably end up getting if I continue to play with this stuff a year or two down the road)

From my understanding the 5v could happily hang out plugged into ground on that same side all day if it wanted to. Is that correct?

No the regulator would over heat and then cut out but you would have damaged it. The output ports are more sensitive that that see the discussion at the end of this page:-
http://www.thebox.myzen.co.uk/Tutorial/LEDs.html

For a discussion on power see:-
http://www.thebox.myzen.co.uk/Tutorial/Power.html

You know you are going to have to get a scope so get it now. It is your eyes, without one you are working blind.

You know you are going to have to get a scope so get it now. It is your eyes, without one you are working blind.

You’re killing me Grumpy Mike! Dont tell me that, I’m teetering on wanting one already… Haha… Any suggestions on a good ebay purchase or some qualities you guys would look for on something used? I’m not a rich man, so new is definitely out of the question…