/Users/fmalpartida/development/ardWorkspace/LiquidCrystal_I2C/LiquiCrystal_I2C/LCD.h

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// ---------------------------------------------------------------------------
// Created by Francisco Malpartida on 20/08/11.
// Copyright 2011 - Under creative commons license 3.0:
//        Attribution-ShareAlike CC BY-SA
//
// This software is furnished "as is", without technical support, and with no 
// warranty, express or implied, as to its usefulness for any purpose.
//
// Thread Safe: No
// Extendable: Yes
//
// @file LCD.h
// This file implements a basic liquid crystal library that comes as standard
// in the Arduino SDK.
// 
// @brief 
// This is a basic implementation of the LiquidCrystal library of the
// Arduino SDK. This library is a refactored version of the one supplied
// in the Arduino SDK in such a way that it simplifies its extension
// to support other mechanism to communicate to LCDs such as I2C, Serial, SR, 
// The original library has been reworked in such a way that this will be
// the base class implementing all generic methods to command an LCD based
// on the Hitachi HD44780 and compatible chipsets.
//
// This base class is a pure abstract class and needs to be extended. As reference,
// it has been extended to drive 4 and 8 bit mode control, LCDs and I2C extension
// backpacks such as the I2CLCDextraIO using the PCF8574* I2C IO Expander ASIC.
//
// The functionality provided by this class and its base class is identical
// to the original functionality of the Arduino LiquidCrystal library.
//
// @version API 1.1.0
//
//
// @author F. Malpartida - fmalpartida@gmail.com
// ---------------------------------------------------------------------------
#ifndef _LCD_H_
#define _LCD_H_

#if (ARDUINO <  100)
#include <WProgram.h>
#else
#include <Arduino.h>
#endif

#include <inttypes.h>
#include <Print.h>


#define FAST_MODE

inline static void waitUsec ( uint16_t uSec )
{
#ifndef FAST_MODE
   delayMicroseconds ( uSec );
#endif // FAST_MODE
}


// LCD Commands
// ---------------------------------------------------------------------------
#define LCD_CLEARDISPLAY        0x01
#define LCD_RETURNHOME          0x02
#define LCD_ENTRYMODESET        0x04
#define LCD_DISPLAYCONTROL      0x08
#define LCD_CURSORSHIFT         0x10
#define LCD_FUNCTIONSET         0x20
#define LCD_SETCGRAMADDR        0x40
#define LCD_SETDDRAMADDR        0x80

// flags for display entry mode
// ---------------------------------------------------------------------------
#define LCD_ENTRYRIGHT          0x00
#define LCD_ENTRYLEFT           0x02
#define LCD_ENTRYSHIFTINCREMENT 0x01
#define LCD_ENTRYSHIFTDECREMENT 0x00

// flags for display on/off and cursor control
// ---------------------------------------------------------------------------
#define LCD_DISPLAYON           0x04
#define LCD_DISPLAYOFF          0x00
#define LCD_CURSORON            0x02
#define LCD_CURSOROFF           0x00
#define LCD_BLINKON             0x01
#define LCD_BLINKOFF            0x00

// flags for display/cursor shift
// ---------------------------------------------------------------------------
#define LCD_DISPLAYMOVE         0x08
#define LCD_CURSORMOVE          0x00
#define LCD_MOVERIGHT           0x04
#define LCD_MOVELEFT            0x00

// flags for function set
// ---------------------------------------------------------------------------
#define LCD_8BITMODE            0x10
#define LCD_4BITMODE            0x00
#define LCD_2LINE               0x08
#define LCD_1LINE               0x00
#define LCD_5x10DOTS            0x04
#define LCD_5x8DOTS             0x00


// Define COMMAND and DATA LCD Rs (used by send method).
// ---------------------------------------------------------------------------
#define COMMAND                 0
#define DATA                    1
#define FOUR_BITS               2


#define HOME_CLEAR_EXEC      2000

#define BACKLIGHT_OFF           0

#define BACKLIGHT_ON          255


typedef enum { POSITIVE, NEGATIVE } t_backlighPol;

class LCD : public Print 
{
public:
   
   LCD ( );
   
   virtual void begin(uint8_t cols, uint8_t rows, uint8_t charsize = LCD_5x8DOTS);
   
   void clear();
   
   void home();
   
   void noDisplay();
   
   void display();
   
   void noBlink();
   
   void blink();
   
   void noCursor();
   
   void cursor();
   
   void scrollDisplayLeft();
   
   void scrollDisplayRight();
   
   void leftToRight();
   
   void rightToLeft();
   
   void moveCursorLeft();
   
   
   void moveCursorRight();
   
   void autoscroll();
   
   void noAutoscroll();
   
   void createChar(uint8_t location, uint8_t charmap[]);
   
   void setCursor(uint8_t col, uint8_t row);
   
   void backlight ( void );
   
   void noBacklight ( void );
   
   void on ( void );

   void off ( void );
   
   //
   // virtual class methods
   // --------------------------------------------------------------------------
   virtual void setBacklightPin ( uint8_t value, t_backlighPol pol ) { };
   
   virtual void setBacklight ( uint8_t value ) { };
   
#if (ARDUINO <  100)
   virtual void write(uint8_t value);
#else
   virtual size_t write(uint8_t value);
#endif
   
#if (ARDUINO <  100)
   using Print::write;
#else
   using Print::write;
#endif   
   
protected:
   // Internal LCD variables to control the LCD shared between all derived
   // classes.
   uint8_t _displayfunction;  // LCD_5x10DOTS or LCD_5x8DOTS, LCD_4BITMODE or 
                              // LCD_8BITMODE, LCD_1LINE or LCD_2LINE
   uint8_t _displaycontrol;   // LCD base control command LCD on/off, blink, cursor
                              // all commands are "ored" to its contents.
   uint8_t _displaymode;      // Text entry mode to the LCD
   uint8_t _numlines;         // Number of lines of the LCD, initialized with begin()
   uint8_t _cols;             // Number of columns in the LCD
   t_backlighPol _polarity;   // Backlight polarity
   
private:
   void command(uint8_t value);

#if (ARDUINO <  100)
   virtual void send(uint8_t value, uint8_t mode) { };
#else
   virtual void send(uint8_t value, uint8_t mode) = 0;
#endif
   
};

#endif