I was running my arduino uno for a couple of hours switching a few led’s on and off. nothing special, flickering them on for around 10millis then off for around 5 seconds. pins 8,9,10,11,12,13 are all wired the same way:-
pin → led → resistor (270ohm) → gnd
all are wired seperately (i.e. 6 led’s and 6 resistors).
this has been working just fine for a few weeks, I use it as a test board. then, suddenly, pin 11 stopped working. nothing unusual, it was sat on my desk merrily blinking away, then suddenly pin 11 stopped blinking.
I’ve measured the output from the pin, the others all read 4.3v and pin11 reads 0.25v, and if I PWM it then it does change, it just maxes out at 0.25v… as though this pin has been “turned down” compared to the others.
I should probably note that I measured it at the pins directly on the chip, so I know it’s definately the chip, not a bad connection on the board.
I suspect the pin is “broken”, is this the case or am I missing something? Is it usual for a broken pin to still be responsive in this way? (namely, still responding and scaling with PWM, but at a much lower voltage).
if so, can i just pop out the chip and pop in a new one?
– edit –
forgot to say which model of arduino i have, it’s the UNO
aaaaand updated with the right resistor value, because my blinky eyes don’t seem to be working today!