m12lrpv:
From the datasheet the atmega328 will only reliably register a low on the a digital pin when the voltage is below 0.3v in a 5v system. It has to be above 0.6V to register as high.
Wrong on both counts.
Read it again.
m12lrpv:
Presumably a continued inability to read on your part.
Pot..kettle...kettle..pot.
Please keep it civil.