diff --git a/cores/arduino/WString.cpp b/cores/arduino/WString.cpp
new file mode 100644
index 0000000..667a304
--- /dev/null
+++ b/cores/arduino/WString.cpp
@@ -0,0 +1,396 @@
+/*
+  WString.cpp - String library for Wiring & Arduino
+  Copyright (c) 2009-10 Hernando Barragan.  All rights reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include <stdlib.h>
+#include "WProgram.h"
+#include "WString.h"
+
+
+String::String( const char *value )
+{
+  if ( value == NULL )
+    value = "";
+  getBuffer( _length = strlen( value ) );
+  strcpy( _buffer, value );
+}
+
+String::String( const String &value )
+{
+  getBuffer( _length = value._length );
+  strcpy( _buffer, value._buffer );
+}
+
+String::String( const char value )
+{
+  _length = 1;
+  getBuffer(1);
+  _buffer[0] = value;
+  _buffer[1] = 0;
+}
+
+String::String( const unsigned char value )
+{
+  _length = 1;
+  getBuffer(1);
+  _buffer[0] = value;
+  _buffer[1] = 0;
+}
+
+String::String( const int value, const int base )
+{
+  char buf[33];   
+  itoa((signed long)value, buf, base);
+  getBuffer( _length = strlen(buf) );
+  strcpy( _buffer, buf );
+}
+
+String::String( const unsigned int value, const int base )
+{
+  char buf[33];   
+  ultoa((unsigned long)value, buf, base);
+  getBuffer( _length = strlen(buf) );
+  strcpy( _buffer, buf );
+}
+
+String::String( const long value, const int base )
+{
+  char buf[33];   
+  ltoa(value, buf, base);
+  getBuffer( _length = strlen(buf) );
+  strcpy( _buffer, buf );
+}
+
+String::String( const unsigned long value, const int base )
+{
+  char buf[33];   
+  ultoa(value, buf, 10);
+  getBuffer( _length = strlen(buf) );
+  strcpy( _buffer, buf );
+}
+
+char String::charAt( unsigned int loc ) const
+{
+	return operator[]( loc );
+}
+
+void String::setCharAt( unsigned int loc, const char aChar ) 
+{
+  if(_length > loc) {
+    _buffer[loc] = aChar;
+  }
+}
+
+int String::compareTo( const String &s2 ) const
+{
+  return strcmp( _buffer, s2._buffer );
+}
+
+const String & String::concat( const String &s2 )
+{
+  return (*this) += s2;
+}
+
+const String & String::operator=( const String &rhs )
+{
+  if ( this == &rhs )
+    return *this;
+
+  if ( rhs._length > _length )
+  {
+    delete [] _buffer;
+    getBuffer( rhs._length );
+  }
+  _length = rhs._length;
+  strcpy( _buffer, rhs._buffer );
+  return *this;
+}
+
+const String & String::operator+=( const char aChar )
+{
+  if ( _length == _capacity )
+    doubleBuffer();
+
+  _buffer[ _length++ ] = aChar;
+  _buffer[ _length ] = '\0';
+  return *this;
+}
+
+const String & String::operator+=( const String &other )
+{
+  _length += other._length;
+  if ( _length > _capacity )
+  {
+    char *temp = _buffer;
+    getBuffer( _length );
+    strcpy( _buffer, temp );
+    delete [] temp;
+  }
+  strcat( _buffer, other._buffer );
+  return *this;
+}
+
+
+int String::operator==( const String &rhs ) const
+{
+  return ( _length == rhs._length && strcmp( _buffer, rhs._buffer ) == 0 );
+}
+
+int String::operator!=( const String &rhs ) const
+{
+  return ( _length != rhs.length() || strcmp( _buffer, rhs.toCharArray() ) != 0 );
+}
+
+int String::operator<( const String &rhs ) const
+{
+  return strcmp( _buffer, rhs._buffer ) < 0;
+}
+
+int String::operator>( const String &rhs ) const
+{
+  return strcmp( _buffer, rhs._buffer ) > 0;
+}
+
+int String::operator<=( const String &rhs ) const
+{
+  return strcmp( _buffer, rhs._buffer ) <= 0;
+}
+
+int String::operator>=( const String & rhs ) const
+{
+  return strcmp( _buffer, rhs._buffer ) >= 0;
+}
+
+char & String::operator[]( unsigned int index )
+{
+  // need to check for valid index, to do later
+  return _buffer[ index ];
+}
+
+char String::operator[]( unsigned int index ) const
+{
+  // need to check for valid index, to do later
+  return _buffer[ index ];
+}
+
+boolean String::endsWith( const String &s2 ) const
+{
+  if ( _length < s2._length )
+    return 0;
+
+  return strcmp( &_buffer[ _length - s2._length], s2.toCharArray() ) == 0;
+}
+
+boolean String::equals( const String &s2 ) const
+{
+  return ( _length == s2._length && strcmp( _buffer,s2._buffer ) == 0 );
+}
+
+boolean String::equalsIgnoreCase( const String &s2 ) const
+{
+  if ( this == &s2 )
+    return true; //1;
+  else if ( _length != s2._length )
+    return false; //0;
+
+  return strcmp(toLowerCase().toCharArray(), s2.toLowerCase().toCharArray()) == 0;
+}
+
+String String::replace( char findChar, char replaceChar )
+{
+  String theReturn = _buffer;
+  char* temp = theReturn._buffer;
+  while( (temp = strchr( temp, findChar )) != 0 )
+    *temp = replaceChar;
+
+  return theReturn;
+}
+
+String String::replace( const String& match, const String& replace )
+{
+  String temp = _buffer, newString;
+
+  int loc;
+  while ( (loc = temp.indexOf( match )) != -1 )
+  {
+    newString += temp.substring( 0, loc );
+    newString += replace;
+    temp = temp.substring( loc + match._length );
+  }
+  newString += temp;  
+  return newString;
+}
+
+int String::indexOf( char temp ) const
+{
+  return indexOf( temp, 0 );
+}
+
+int String::indexOf( char ch, unsigned int fromIndex ) const
+{
+  if ( fromIndex >= _length )
+    return -1;
+
+  const char* temp = strchr( &_buffer[fromIndex], ch );
+  if ( temp == NULL )
+    return -1;
+
+  return temp - _buffer;
+}
+
+int String::indexOf( const String &s2 ) const
+{
+  return indexOf( s2, 0 );
+}
+
+int String::indexOf( const String &s2, unsigned int fromIndex ) const
+{
+  if ( fromIndex >= _length )
+    return -1;
+
+  const char *theFind = strstr( &_buffer[ fromIndex ], s2.toCharArray() );
+
+  if ( theFind == NULL )
+    return -1;
+
+  return theFind - _buffer; // pointer subtraction
+}
+
+int String::lastIndexOf( char theChar ) const
+{
+  return lastIndexOf( theChar, _length - 1 );
+}
+
+int String::lastIndexOf( char ch, unsigned int fromIndex ) const
+{
+  if ( fromIndex >= _length )
+    return -1;
+
+  char tempchar = _buffer[fromIndex + 1];
+  _buffer[fromIndex + 1] = '\0';
+  char* temp = strrchr( _buffer, ch );
+  _buffer[fromIndex + 1] = tempchar;
+
+  if ( temp == NULL )
+    return -1;
+
+  return temp - _buffer;
+}
+
+int String::lastIndexOf( const String &s2 ) const
+{
+  return lastIndexOf( s2, _length - s2._length );
+}
+
+int String::lastIndexOf( const String &s2, unsigned int fromIndex ) const
+{
+  // check for empty strings
+  if ( s2._length == 0 || s2._length - 1 > fromIndex || fromIndex >= _length )
+    return -1;
+
+  // matching first character
+  char temp = s2[ 0 ];
+
+  for ( int i = fromIndex; i >= 0; i-- )
+  {
+    if ( _buffer[ i ] == temp && (*this).substring( i, i + s2._length ).equals( s2 ) )
+    return i;
+  }
+  return -1;
+}
+
+boolean String::startsWith( const String &s2 ) const
+{
+  if ( _length < s2._length )
+    return 0;
+
+  return startsWith( s2, 0 );
+}
+
+boolean String::startsWith( const String &s2, unsigned int offset ) const
+{
+  if ( offset > _length - s2._length )
+    return 0;
+
+  return strncmp( &_buffer[offset], s2.toCharArray(), s2._length ) == 0;
+}
+
+String String::substring( unsigned int left ) const
+{
+  return substring( left, _length );
+}
+
+String String::substring( unsigned int left, unsigned int right ) const
+{
+  if ( left > right )
+  {
+    int temp = right;
+    right = left;
+    left = temp;
+  }
+
+  if ( right > _length )
+  {
+    right = _length;
+  } 
+
+  char temp = _buffer[ right ];  // save the replaced character
+  _buffer[ right ] = '\0';	
+  String outPut = ( _buffer + left );  // pointer arithmetic
+  _buffer[ right ] = temp;  //restore character
+  return outPut;
+}
+
+String String::toLowerCase() const
+{
+  String temp = _buffer;
+
+  for ( unsigned int i = 0; i < _length; i++ )
+    temp._buffer[ i ] = (char)tolower( temp._buffer[ i ] );
+  return temp;
+}
+
+String String::toUpperCase() const
+{
+  String temp = _buffer;
+
+  for ( unsigned int i = 0; i < _length; i++ )
+    temp._buffer[ i ] = (char)toupper( temp._buffer[ i ] );
+  return temp;
+}
+
+String String::trim() const
+{
+  String temp = _buffer;
+  unsigned int i,j;
+
+  for ( i = 0; i < _length; i++ )
+  {
+    if ( !isspace(_buffer[i]) )
+      break;
+  }
+
+  for ( j = temp._length - 1; j > i; j-- )
+  {
+    if ( !isspace(_buffer[j]) )
+      break;
+  }
+
+  return temp.substring( i, j + 1);
+}
+
diff --git a/cores/arduino/WString.h b/cores/arduino/WString.h
new file mode 100644
index 0000000..c93d493
--- /dev/null
+++ b/cores/arduino/WString.h
@@ -0,0 +1,119 @@
+/*
+  WString.h - String library for Wiring & Arduino
+  Copyright (c) 2009-10 Hernando Barragan.  All right reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef String_h
+#define String_h
+
+#include "WProgram.h"
+#include <string.h>
+#include <ctype.h>
+
+class String
+{
+  public:
+    // constructors
+    String( const char *value = "" );
+    String( const String &value );
+    explicit String( const char );
+    explicit String( const unsigned char );
+    explicit String( const int, const int base=10);
+    explicit String( const unsigned int, const int base=10 );
+    explicit String( const long, const int base=10 );
+    explicit String( const unsigned long, const int base=10 );
+    virtual ~String() { delete [] _buffer; }
+
+    // operators
+    const String & operator = ( const String &rhs );
+    const String & operator +=( const String &rhs );
+    const String & operator +=( const char );
+    int operator ==( const String &rhs ) const;
+    int	operator !=( const String &rhs ) const;
+    int	operator < ( const String &rhs ) const;
+    int	operator > ( const String &rhs ) const;
+    int	operator <=( const String &rhs ) const;
+    int	operator >=( const String &rhs ) const;
+    char operator []( unsigned int index ) const;
+    char& operator []( unsigned int index );
+//    operator const char *() const { return _buffer; }
+
+    // general methods
+    char charAt( unsigned int index ) const;
+    int	compareTo( const String &anotherString ) const;
+    boolean endsWith( const String &suffix ) const;
+    boolean equals( const String &anObject ) const;
+    boolean equalsIgnoreCase( const String &anotherString ) const;
+    int	indexOf( char ch ) const;
+    int	indexOf( char ch, unsigned int fromIndex ) const;
+    int	indexOf( const String &str ) const;
+    int	indexOf( const String &str, unsigned int fromIndex ) const;
+    int	lastIndexOf( char ch ) const;
+    int	lastIndexOf( char ch, unsigned int fromIndex ) const;
+    int	lastIndexOf( const String &str ) const;
+    int	lastIndexOf( const String &str, unsigned int fromIndex ) const;
+    const unsigned int length( ) const { return _length; }
+    void setCharAt(unsigned int index, const char ch);
+    boolean startsWith( const String &prefix ) const;
+    boolean startsWith( const String &prefix, unsigned int toffset ) const;
+    String substring( unsigned int beginIndex ) const;
+    String substring( unsigned int beginIndex, unsigned int endIndex ) const;
+    String toLowerCase( ) const;
+    String toUpperCase( ) const;
+    String trim( ) const;
+    const byte *getBytes() const { return (byte*)_buffer; }
+    const char* toCharArray() const { return _buffer; }
+    const String& concat( const String &str );
+    String replace( char oldChar, char newChar );
+    String replace( const String& match, const String& replace );
+    friend String operator + ( String lhs, const String &rhs );
+
+  protected:
+    char *_buffer;	     // the actual char array
+    unsigned int _capacity;  // the array length
+    unsigned int _length;    // the String length
+
+    void getBuffer(unsigned int maxStrLen);
+    void doubleBuffer( );
+
+  private:
+
+};
+
+// allocate buffer space
+inline void String::getBuffer(unsigned int maxStrLen)
+{
+  _capacity = maxStrLen;
+  _buffer = new char[_capacity + 1];
+}
+
+// double the buffer size
+inline void String::doubleBuffer( )
+{
+  char *temp = _buffer;
+  getBuffer( ++_capacity * 2 );
+  strcpy( _buffer, temp );
+  delete [] temp;
+}
+
+inline String operator+( String lhs, const String &rhs )
+{
+  return lhs += rhs;
+}
+
+
+#endif