I think I read somwhere that I can connect an LED between pin 13 and ground without using a series resistor on a rev 3 uno, anyone know if this is correct?
richmc:
I think I read somwhere that I can connect an LED between pin 13 and ground without using a series resistor on a rev 3 uno, anyone know if this is correct?
No, that is not correct. A resistor is required.
Lefty
Thanks Lefty, must have drempt it! 
No, that is not correct.
Depends... I thought he was asking if it was correct that he read it somewhere.... but we wouldn't know
richmc:
Thanks Lefty, must have drempt it!
No you did not dream it, it's one of the most common errors around on the net. Back in 2006 ( I think ) there was a resistor in series with this pin so you could do that. However it screwed up using SPI so it was dropped. The concept however remains mainly propagated by people who do not understand what they are doing. I have seen in in several published books telling me, and everyone else, that the authors are idiots.
Grumpy_Mike:
richmc:
Thanks Lefty, must have drempt it!No you did not dream it, it's one of the most common errors around on the net. Back in 2006 ( I think ) there was a resistor in series with this pin so you could do that. However it screwed up using SPI so it was dropped. The concept however remains mainly propagated by people who do not understand what they are doing. I have seen in in several published books telling me, and everyone else, that the authors are idiots.
Hm, that explains my first book then, haha.
JimboZA:
No, that is not correct.
Depends... I thought he was asking if it was correct that he read it somewhere.... but we wouldn't know
Ah the enevitable gramatical pedant!(every forun needs one) Guess what, I'm not saying. 
That would be "inevitable" 8)
JimboZA:
That would be "inevitable" 8)
Nerd. 
Shouldn't that be nird?
JimboZA:
Shouldn't that be nird?
Poo go away, querstion answered, thank you, look forward to more fun answerers. 8)