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This example is for Wiring version 1.0 build 0100+. If you have a previous version, use the examples included with your software. If you see any errors or have comments, please let us know.

CharacterAnalysis by Tom Igoe
Examples using the character analysis operators. Send any byte and the sketch will tell you about it.

    void setup()
    {
      // Open serial communications:
      Serial.begin(9600);

      // send an intro:
      Serial.println("send any byte and I'll tell you everything I can about it");
      Serial.println();
    }

    void loop()
    {
      // get any incoming bytes:
      if (Serial.available() > 0)
      {
        int thisChar = Serial.read();

        // say what was sent:
        Serial.print("You sent me: \'");
        Serial.write(thisChar);
        Serial.print("\'  ASCII Value: ");
        Serial.println(thisChar);

        // analyze what was sent:
        if (isAlphaNumeric(thisChar))
        {
          Serial.println("it's alphanumeric");
        }
        if (isAlpha(thisChar))
        {
          Serial.println("it's alphabetic");
        }
        if (isAscii(thisChar))
        {
          Serial.println("it's ASCII");
        }
        if (isWhitespace(thisChar))
        {
          Serial.println("it's whitespace");
        }
        if (isControl(thisChar))
        {
          Serial.println("it's a control character");
        }
        if (isDigit(thisChar))
        {
          Serial.println("it's a numeric digit");
        }
        if (isGraph(thisChar))
        {
          Serial.println("it's a printable character that's not whitespace");
        }
        if (isLowerCase(thisChar))
        {
          Serial.println("it's lower case");
        }
        if (isPrintable(thisChar))
        {
          Serial.println("it's printable");
        }
        if (isPunct(thisChar))
        {
          Serial.println("it's punctuation");
        }
        if (isSpace(thisChar))
        {
          Serial.println("it's a space character");
        }
        if (isUpperCase(thisChar))
        {
          Serial.println("it's upper case");
        }
        if (isHexadecimalDigit(thisChar))
        {
          Serial.println("it's a valid hexadecimaldigit (i.e. 0 - 9, a - F, or A - F)");
        }

        // add some space and ask for another byte:
        Serial.println();
        Serial.println("Give me another byte:");
        Serial.println();
      }
    }