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?
It depends on the relative resistance of the pull-up and the LDR.
KeithB:
It depends on the relative resistance of the pull-up and the LDR.
100k - 10M ohm ldr
Have read that one. I just might be stupid but i couldnt get the answer im after from that.
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!
It means they exist and act the same way as they do on the digital ports. So you won't hurt your Arduino by enabling them. So my take is you can try, it won't hurt, but it's not guaranteed to work.hneve:
Have read that one. I just might be stupid but i couldnt get the answer im after from that.
Mee_n_Mac:
It means they exist and act the same way as they do on the digital ports. So you won't hurt your Arduino by enabling them. So my take is you can try, it won't hurt, but it's not guaranteed to work.hneve:
Have read that one. I just might be stupid but i couldnt get the answer im after from that.
Thank you 
I will try, really just nedded to know if it would harm the uno.