Arduino Due defective??

Using Arduino IDE 1.x
1

Hi! I have an Arduino Due for a few days and I think its inputs malfunctioning.
When I was testing this simple code WITHOUT ANY INPUT CONNECTED:
void setup() {
** pinMode(42,INPUT);**
** Serial.begin(9600);**
** }**
** void loop() {**
** Serial.print(digitalRead(42));**
** delay(1000);**
** }**

This is the result (on the input 42 in this example, but I tested it on other inputs analogs and digitals and I had the same result)
111111111000000111111000111111111111100000000000111111.......

It is because my Arduino Due have a malfunctioning? I have not got any connection on this pin, and I tested it with a little button not preessed and I had the same result, why is it? is it normal?

2

https://www.google.com/search?q=unconnected+pin+defective+site:arduino.cc%2Fforum

3

tonyvlc:
is it normal?

Yes, if nothing is connected what would you expect? Of course you will probably say "nothing" or "zero". But if nothing is connected, then the pin is picking up whatever stray energy is around it. It is called "floating".

Videos of what happens with a floating pin and explanation of how to use the internal pull-up resistors:
http://www.cmiyc.com/tutorials/arduino-pull-ups/

Written for a Uno but will apply to a Due just the same.

You can also call pinmode with INPUT_PULLUP to enable the pull-up. (My tutorial was written before that was an option.)