I got an Arduino Mega some weeks ago. It is really a masterpiece, but I came to a point that I think is a big problem (at least for me). I connected the common +5 via 2.2k resistor to dig input and i started reading it. When the +5 is on i got "1" on Serial.print(pin, BIN) and it was stable. But when the +5 are gone (via switch or sth) the "0" are all but stable. If you ask me a percentage - 5% wrong.
Has anyone experienced this too? What sould i do to read "0" for 0V?