I2cLcd.h

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/*
    I2cLcd.h - Tools for using an I2C-based LCD such as the
    Adafruit RGB 16x2 LCD Shield .
    For AVR ATMega328p (Arduino Uno) and ATMega2560 (Arduino Mega).
    This is part of the AVRTools library.
    Copyright (c) 2014 Igor Mikolic-Torreira.  All right reserved.

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program 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 General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/


#ifndef I2cLcd_h
#define I2cLcd_h

#include <inttypes.h>
#include "Writer.h"




class I2cLcd : public Writer
{
public:

    enum
    {
        kButton_Select   = 0x01,        
        kButton_Right    = 0x02,        
        kButton_Down     = 0x04,        
        kButton_Up       = 0x08,        
        kButton_Left     = 0x10         
    };


    enum
    {
        kBacklight_Red      = 0x1,        
        kBacklight_Yellow   = 0x3,        
        kBacklight_Green    = 0x2,        
        kBacklight_Teal     = 0x6,        
        kBacklight_Blue     = 0x4,        
        kBacklight_Violet   = 0x5,        
        kBacklight_White    = 0x7         
    };


    I2cLcd();


    int init();


    void clear();


    void home();


    void displayTopRow( const char* str );


    void displayBottomRow( const char* str );


    void clearTopRow();


    void clearBottomRow();



    void displayOff();


    void displayOn();


    void blinkOff();


    void blinkOn();


    void cursorOff();


    void cursorOn();


    void scrollDisplayLeft();


    void scrollDisplayRight();


    void autoscrollOn();


    void autoscrollOff();


    void setCursor( uint8_t row, uint8_t col );


    int setBacklight( uint8_t color );


    void command( uint8_t cmd );


    uint8_t readButtons();



    virtual size_t write( char c );


    virtual size_t write( const char* str );


    virtual size_t write( const char* buffer, size_t size );


    virtual size_t write( const uint8_t* buffer, size_t size );


    virtual void flush();


private:

    enum
    {
        kWriteFourBitsSendChar = 0,
        kWriteFourBitsSendCommand = 1
    };

    int initMCP23017();
    int initHD44780U();
    size_t write( uint8_t value );
    int writeFourBitsToLcd( uint8_t value, uint8_t gpioB );
    int sendCharOrCmdToLcd( uint8_t value, bool isCommand );

    int sendCommand( uint8_t cmd )
    {
        return sendCharOrCmdToLcd( cmd, kWriteFourBitsSendCommand );
    }

    int sendCharToDisplay( uint8_t value )
    {
        return sendCharOrCmdToLcd( value, kWriteFourBitsSendChar );
    }

    uint8_t             mDisplayControl;
    uint8_t             mDisplayMode;
    uint8_t             mCurrLine;
    volatile uint8_t    mI2cStatus;
};

#endif