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//>>> The latest version of this code can be found at https://github.com/jcw/ !!

// LiquidCrystal library, extended for use over I2C with the LCD Plug

// 2009-09-23 <jcw@equi4.com> http://opensource.org/licenses/mit-license.php

// $Id$

// see http://news.jeelabs.org/2009/09/26/generalized-liquidcrystal-library/

#ifndef LiquidCrystal_h

#define LiquidCrystal_h

#include <inttypes.h>

#include <Print.h>

#include <Ports.h>

// 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 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

// this class defines all the basic functionality needed to drive an LCD display

// it is an incomplete (abstract) base class, which needs to be extended for use

// see the LiquidCrystal and LiquidCrystalI2C classes for two usable versions

class LiquidCrystalBase : public Print {

public:

  LiquidCrystalBase () {}

  void begin(byte cols, byte rows, byte 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 autoscroll();

  void noAutoscroll();

  void createChar(byte, byte[]);

  void setCursor(byte, byte);

  virtual void write(byte);

  void command(byte);

protected:

  virtual void config() =0;

  virtual void send(byte, byte) =0;

  virtual void write4bits(byte) =0;

  byte _displayfunction;

  byte _displaycontrol;

  byte _displaymode;

  byte _initialized;

  byte _numlines,_currline;

};

// This class can be used to create an object with drives an LCD through many

// different I/O pins, connected to the display in parallel - it is equivalent

// to the LiquidCrystal class defined in the Arduino, but has be adjusted to

// work with the above LiquidCrystalBase instead.

class LiquidCrystal : public LiquidCrystalBase {

public:

  LiquidCrystal(byte rs, byte enable,

                byte d0, byte d1, byte d2, byte d3, byte d4, byte d5, byte d6, byte d7);

  LiquidCrystal(byte rs, byte rw, byte enable,

                byte d0, byte d1, byte d2, byte d3, byte d4, byte d5, byte d6, byte d7);

  LiquidCrystal(byte rs, byte rw, byte enable,

                byte d0, byte d1, byte d2, byte d3);

  LiquidCrystal(byte rs, byte enable,

                byte d0, byte d1, byte d2, byte d3);

  void init(byte fourbitmode, byte rs, byte rw, byte enable,

            byte d0, byte d1, byte d2, byte d3, byte d4, byte d5, byte d6, byte d7);

  virtual void config();

  virtual void send(byte, byte);

  virtual void write4bits(byte);

  void write8bits(byte);

  void pulseEnable();

  byte _rs_pin; // LOW: command.  HIGH: character.

  byte _rw_pin; // LOW: write to LCD.  HIGH: read from LCD.

  byte _enable_pin; // activated by a HIGH pulse.

  byte _data_pins[8];

};

// This class allows driving an LCD connected via I2C using an LCD Plug, which

// is in turn based on an MCP23008 I2C I/O expander chip and some other parts.

// The available functions include all those of the LiquidCrystal class.

class LiquidCrystalI2C : public LiquidCrystalBase {

  DeviceI2C device;

public:

  LiquidCrystalI2C (const PortI2C& p, byte addr =0x24);

  // this display can also turn the back-light on or off

  void backlight();

  void noBacklight();

protected:

  virtual void config();

  virtual void send(byte, byte);

  virtual void write4bits(byte);

};

#endif