Hi. Have googled but not gotten any smarter. Ok. If i set A0 as input then do a digitalwrite(A0, HIGH) to set pullup. Then place a ldr between pin A0 and ground. Q: will this fry my Uno? Or will i be able to get any reading of light from it?

Uno r3 analog & pullup

KeithB February 5, 2013, 8:29pm 6

I said relative, which means that the resistance of the Arduino pull-up - which I do not know off hand - matters.

You would have found out by now if you would have just tried it!

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