analogRead() returns junk when I print via serial [Arduino]

Question

I'm making a clock with the Arduino and I want to make a button to set the time. So, just to test, I pluged a wire in the Analog Input pin 0 and wrote two lines of code to read the pin an print it via Serial, but all I get is junk.

  valm = analogRead(0);
  Serial.println(valm);

And what I get from the serial monitor is this:

?j?d?±µ?Ê??jDd?±µ???ºjRd?±µ???ºj?d?±µ?Ê??j?d?±µ?É?ªjRd?±µ???ÊjRd?±µ???Âj?d?±µ????j?d?±µ?É??j
Rd?±µ????j?d?±µ???ºj?d?±µ?É??jRd?±µ????j?d?±µ?Ê?ÊjDd?±µ???Âj?d?±µ????j?d?±µ?É??jRd?±µ????j?d
?±µ?É?ÂjRd?±µ???Êj?d?±µ???ªj?d?±µ?Ê?Êj$d?±µ???ÂjRd?±µ????j?d?±µ????jdd?±µ????jRd?±µ???Âj?d?±
µ?É?ÊjRd?±µ????j?d?±µ?Ò?Êj?d?±µ?É?ÂjRd?±µ????j?d?±µ????j?d?±µ?É??jRd?±µ???Âj?d?±µ???Êj?d?±µ?
??ªj?d?±µ???Êj?d?±µ???ÂjRd?±µ????j?d?±µ????j?d?±µ?É??jRd?±µ???Âj?d?±µ?Ò?Êj?d?±µ?É?ªj?d?±µ?É?
?jTd?±µ???Âj?d?±µ????j?d?±µ?É??jRd?±µ????j?d?±µ?É?ÂjRd?±µ???Êj?d?±µ?É?ªjRd?±µ???Êj?d?±µ???ºj
?d?±µ?È??jTd?±µ????jRd?±µ???ªj?d?±µ?È?ÂjTd?±µ?É?ÊjRd?±µ???ªj?d?±µ???Êj?d?±µ???ºj?d?±µ?É??jRd
?±µ???Êj?d?±µ???ªj?d?±µ?É?ÂjPd?±µ???Êj?d?±µ???ªj?d?±µ?Â?Êj?d?±µ?É?ºjRd?±µ????j?d?±µ?É??jRd?±
µ???ªj?d?±µ?Ê?Âj?d?±µ???ÊjRd?±µ???ªj?d?±µ?Ò?Êj?d?±µ???ºjRd?±µ????j?d?±µ???Êj?d?±µ?Ê?ªjdd?±µ?
??ÂjRd?±µ???Âj?d?±µ?É?ªjPd?±µ???Êj?d?±µ????j?d?±µ?É??jRd?±µ???Êj?d?±µ?É?ªjdd?±µ???ÂjRd?±µ???
Âj?d?±µ?É?ªjDd?±µ???Êj?d?±µ?Ê??j?d?±µ?É??jRd?±µ???ÊjRd?±µ???ªj?d?±µ?Ê?ÂjPd?±µ???Âj?d?±µ???ªj
?d?±µ?É?Êjdd?±µ?É??jRd?±µ????j?d?±µ?É?Êj$d?±µ???ªjRd?±µ???Âj?d?±µ?Â?ÂjTd?±µ???ªj?d?±µ???Êj?d
?±µ????jRd?±µ????j?d?±µ?É?ÊjTd?±µ???ªjRd?±µ???Âj?d?±µ???Âj?d?±µ?É?ªjRd?±µ???ÊjRd?±µ?Ò??jTd?±
µ????j?d?±µ???Êj

Anyone know why?

Edit:

I had set the digital pin 0 to output, and I tought maybe that was the probleme so I went to the Arduino website and found this page (http://arduino.cc/en/Tutorial/AnalogInputPins)

So I tried to Read from the pin 14 wich they say is the analog input pin 0, but i got the same output.

By the way, I'm trying to read from the analog only pins, not the one wich are also digital.

Answer 1

From what your output looks like, it seems like you need to convert valm into a string, so that you can print the value numerically.

Also, is the wire you plugged into analog in floating? Because if it is, it'll just act like an antenna and grab random noise (though, might have a strong 60Hz component).

Answer 2

Try running this sample code found on the arduino website. You shouldn't need to convert valm or anything.

/*
  Analog input

 reads an analog input on analog in 0, prints the value out.

 created 24 March 2006
 by Tom Igoe
 */

int analogValue = 0;    // variable to hold the analog value

void setup() {
  // open the serial port at 9600 bps:
  Serial.begin(9600);
}

void loop() {
  // read the analog input on pin 0:
  analogValue = analogRead(0);

  // print it out in many formats:
  Serial.println(analogValue);       // print as an ASCII-encoded decimal
  Serial.println(analogValue, DEC);  // print as an ASCII-encoded decimal
  Serial.println(analogValue, HEX);  // print as an ASCII-encoded hexadecimal
  Serial.println(analogValue, OCT);  // print as an ASCII-encoded octal
  Serial.println(analogValue, BIN);  // print as an ASCII-encoded binary
  Serial.println(analogValue, BYTE); // print as a raw byte value

  // delay 10 milliseconds before the next reading:
  delay(10);
}

If your output is still gibberish, there's something wrong with your serial terminal.