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Author Topic: Now I really need help.  (Read 700 times)
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None of my digital pins, except for pin 13, work. They all ouput ~4VDC and almost no current-- a 3mm green led plugged in to any of them stays off. (I wrote some simple code which pulls pins 2-13 high.)
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did you remember the pinMode(n, OUTPUT); statement in setup?  the behavior you describe is typical of leaving that out, in which case writing HIGH enables the internal pull-up resistor (about 30k[ch937]; very weak.)
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Thanks!
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And you have a 330ohm or so current limit resister in series with your LED also so you don't damage the output?
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Yes.
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