LiquidCrystal_I2C.cpp

#include "LiquidCrystal_I2C.h"

#if defined(ARDUINO) 
    #include "ArduinoImpl.h"
#else
    #include "RPIImpl.h"
#endif

#include <inttypes.h>
#include <stdio.h>
#include <string.h>

// When the display powers up, it is configured as follows:
//
// 1. Display clear
// 2. Function set: 
//    DL = 1; 8-bit interface data 
//    N = 0; 1-line display 
//    F = 0; 5x8 dot character font 
// 3. Display on/off control: 
//    D = 0; Display off 
//    C = 0; Cursor off 
//    B = 0; Blinking off 
// 4. Entry mode set: 
//    I/D = 1; Increment by 1
//    S = 0; No shift 
//
// Note, however, that resetting the Arduino doesn't reset the LCD, so we
// can't assume that its in that state when a sketch starts (and the
// LiquidCrystal constructor is called).

LiquidCrystal_I2C::LiquidCrystal_I2C(uint8_t lcd_Addr,uint8_t lcd_cols,uint8_t lcd_rows)
{
    _Addr = lcd_Addr;
    _cols = lcd_cols;
    _rows = lcd_rows;
    _backlightval = LCD_NOBACKLIGHT;
    _adapter = 2;
    createDevice();
}

LiquidCrystal_I2C::LiquidCrystal_I2C(uint8_t lcd_Addr, uint8_t lcd_cols,
uint8_t lcd_rows, uint8_t lcd_adapter)
{
    _Addr = lcd_Addr;
    _cols = lcd_cols;
    _rows = lcd_rows;
    _backlightval = LCD_NOBACKLIGHT;
    _adapter = lcd_adapter;
    createDevice();
}

// compile time factory to get proper implementation class

void LiquidCrystal_I2C::createDevice()
{
#if defined(ARDUINO) 
    _pImpl = new ArduinoImpl(_Addr, _cols, _rows);
#else
    _pImpl = new RPIImpl(_Addr, _cols, _rows, _adapter);
#endif
    _pImpl->setBacklightVal(_backlightval);
}

void LiquidCrystal_I2C::write(uint8_t value) 
{
    send(value, Rs);
}

void LiquidCrystal_I2C::oled_init()
{
    _oled = true;
    init_priv();
}

void LiquidCrystal_I2C::init()
{
    init_priv();
}

void LiquidCrystal_I2C::init_priv()
{
    _pImpl->init_priv(); // Wire.begin() on arduino;
    _displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS;
    begin(_cols, _rows);
}

void LiquidCrystal_I2C::begin(uint8_t cols, uint8_t lines, uint8_t dotsize) 
{
    if (lines > 1) {
        _displayfunction |= LCD_2LINE;
    }

    _numlines = lines;

    // for some 1 line displays you can select a 10 pixel high font
    if ((dotsize != 0) && (lines == 1)) {
        _displayfunction |= LCD_5x10DOTS;
    }

    // SEE PAGE 45/46 FOR INITIALIZATION SPECIFICATION!
    // according to datasheet, we need at least 40ms after power rises above 2.7V
    // before sending commands. Arduino can turn on way befer 4.5V so we'll wait 50

    _pImpl->delayMilliseconds(50); 
  
    // Now we pull both RS and R/W low to begin commands

    expanderWrite(_backlightval);	// reset expanderand turn backlight off (Bit 8 =1)
    _pImpl->delayMilliseconds(1000);

    //put the LCD into 4 bit mode
    // this is according to the hitachi HD44780 datasheet
    // figure 24, pg 46
	
    // we start in 8bit mode, try to set 4 bit mode
 
    write4bits(0x03 << 4);
    _pImpl->delayMicroseconds(4500); // wait min 4.1ms
   
    // second try
    write4bits(0x03 << 4);
    _pImpl->delayMicroseconds(4500); // wait min 4.1ms
   
    // third go!
    write4bits(0x03 << 4); 
    _pImpl->delayMicroseconds(150);
   
    // finally, set to 4-bit interface
    write4bits(0x02 << 4); 

    // set # lines, font size, etc.
    command(LCD_FUNCTIONSET | _displayfunction);  
	
    // turn the display on with no cursor or blinking default
    _displaycontrol = LCD_DISPLAYON | LCD_CURSOROFF | LCD_BLINKOFF;
    display();
	
    // clear it off
    clear();
	
    // Initialize to default text direction (for roman languages)
    _displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;
	
    // set the entry mode
    command(LCD_ENTRYMODESET | _displaymode);
	
    home();
}

/********** high level commands, for the user! */
void LiquidCrystal_I2C::clear()
{
    command(LCD_CLEARDISPLAY);// clear display, set cursor position to zero
    _pImpl->delayMicroseconds(2000);  // this command takes a long time!
    if (_oled) {
        setCursor(0,0);
    }
}

void LiquidCrystal_I2C::delay(int ms)
{
    _pImpl->delayMilliseconds(ms);
}

void LiquidCrystal_I2C::home()
{
    command(LCD_RETURNHOME);  // set cursor position to zero
    _pImpl->delayMicroseconds(2000);  // this command takes a long time!
}

void LiquidCrystal_I2C::setCursor(uint8_t col, uint8_t row)
{
    int row_offsets[] = { 0x00, 0x40, 0x14, 0x54 };
    if ( row > _numlines ) {
        row = _numlines-1;    // we count rows starting w/0
    }
    command(LCD_SETDDRAMADDR | (col + row_offsets[row]));
}

// Turn the display on/off (quickly)
void LiquidCrystal_I2C::noDisplay() 
{
    _displaycontrol &= ~LCD_DISPLAYON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

void LiquidCrystal_I2C::display() 
{
    _displaycontrol |= LCD_DISPLAYON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// Turns the underline cursor on/off
void LiquidCrystal_I2C::noCursor() 
{
    _displaycontrol &= ~LCD_CURSORON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

void LiquidCrystal_I2C::cursor() 
{
    _displaycontrol |= LCD_CURSORON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// Turn on and off the blinking cursor
void LiquidCrystal_I2C::noBlink() 
{
    _displaycontrol &= ~LCD_BLINKON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

void LiquidCrystal_I2C::blink() 
{
    _displaycontrol |= LCD_BLINKON;
    command(LCD_DISPLAYCONTROL | _displaycontrol);
}

// These commands scroll the display without changing the RAM
void LiquidCrystal_I2C::scrollDisplayLeft(void) 
{
    command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVELEFT);
}

void LiquidCrystal_I2C::scrollDisplayRight(void) 
{
    command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVERIGHT);
}

// This is for text that flows Left to Right
void LiquidCrystal_I2C::leftToRight(void) 
{
    _displaymode |= LCD_ENTRYLEFT;
    command(LCD_ENTRYMODESET | _displaymode);
}

// This is for text that flows Right to Left
void LiquidCrystal_I2C::rightToLeft(void) 
{
    _displaymode &= ~LCD_ENTRYLEFT;
    command(LCD_ENTRYMODESET | _displaymode);
}

// This will 'right justify' text from the cursor
void LiquidCrystal_I2C::autoscroll(void) 
{
    _displaymode |= LCD_ENTRYSHIFTINCREMENT;
    command(LCD_ENTRYMODESET | _displaymode);
}

// This will 'left justify' text from the cursor
void LiquidCrystal_I2C::noAutoscroll(void) 
{
    _displaymode &= ~LCD_ENTRYSHIFTINCREMENT;
    command(LCD_ENTRYMODESET | _displaymode);
}

// Allows us to fill the first 8 CGRAM locations
// with custom characters
void LiquidCrystal_I2C::createChar(uint8_t location, uint8_t charmap[]) 
{
    location &= 0x7; // we only have 8 locations 0-7
    command(LCD_SETCGRAMADDR | (location << 3));
    for (int i=0; i<8; i++) {
        write(charmap[i]);
    }
}

#if 0
//createChar with PROGMEM input
void LiquidCrystal_I2C::createChar(uint8_t location, const char *charmap) 
{
    Serial.print("createChar 2\n");
    location &= 0x7; // we only have 8 locations 0-7
    command(LCD_SETCGRAMADDR | (location << 3));
    for (int i=0; i<8; i++) {
        write(pgm_read_byte_near(charmap++));
    }
}
#endif

// Turn the (optional) backlight off/on
void LiquidCrystal_I2C::noBacklight(void) 
{
    _backlightval=LCD_NOBACKLIGHT;
    _pImpl->setBacklightVal(_backlightval);
    expanderWrite(0);
}

void LiquidCrystal_I2C::backlight(void) 
{
    _backlightval=LCD_BACKLIGHT;
    _pImpl->setBacklightVal(_backlightval);
    expanderWrite(0);
}

/*********** mid level commands, for sending data/cmds */

inline void LiquidCrystal_I2C::command(uint8_t value) 
{
    send(value, 0);
}

/************ low level data pushing commands **********/

// write either command or data
void LiquidCrystal_I2C::send(uint8_t value, uint8_t mode) 
{
    uint8_t highnib=value&0xf0;
    uint8_t lownib=(value<<4)&0xf0;
    write4bits((highnib)|mode);
    write4bits((lownib)|mode); 
}

void LiquidCrystal_I2C::write4bits(uint8_t value) 
{
    expanderWrite(value);
    pulseEnable(value);
}

void LiquidCrystal_I2C::expanderWrite(uint8_t _data)
{                                        
    _pImpl->expanderWrite(_data);
}

void LiquidCrystal_I2C::pulseEnable(uint8_t _data){
    expanderWrite(_data | En);	// En high
    _pImpl->delayMicroseconds(1);		// enable pulse must be >450ns
    expanderWrite(_data & ~En);	// En low
    _pImpl->delayMicroseconds(50);		// commands need > 37us to settle
} 

// Alias functions

void LiquidCrystal_I2C::cursor_on()
{
    cursor();
}

void LiquidCrystal_I2C::cursor_off()
{
    noCursor();
}

void LiquidCrystal_I2C::blink_on()
{
    blink();
}

void LiquidCrystal_I2C::blink_off()
{
    noBlink();
}

void LiquidCrystal_I2C::load_custom_character(uint8_t char_num, uint8_t *rows)
{
    createChar(char_num, rows);
}

void LiquidCrystal_I2C::setBacklight(uint8_t new_val)
{
    if (new_val) {
        backlight();		// turn backlight on
    } else {
        noBacklight();		// turn backlight off
    }
}

void LiquidCrystal_I2C::printstr(const char c[])
{
    //This function is not identical to the function used for "real" I2C displays
    //it's here so the user sketch doesn't have to be changed 
    print(c);
}

// replace the Arduino implemented Print with our own 

size_t LiquidCrystal_I2C::print(const char arg1[])
{
    for (int i = 0; i < strlen(arg1); i++) {
        print(arg1[i]);
    }
    return strlen(arg1);
}

size_t LiquidCrystal_I2C::print(char arg1)
{
    write(arg1);
    return 1;
}

size_t LiquidCrystal_I2C::print(unsigned char arg1, int base)
{
    return print(((int) arg1) & 0xff, base);
}

size_t LiquidCrystal_I2C::print(int arg1, int base) 
{
    // XXX this works if value is not negative

    return print(((unsigned int) arg1) & 0xff, base);
}

size_t LiquidCrystal_I2C::print(unsigned int arg1, int base)
{
    char buf[4];
    char format[4];

    if (base == HEX) {
        strcpy(format, "%x");
    } else {
        strcpy(format, "%o");
    }
    snprintf(buf, sizeof(buf), format, arg1);
    for (int i = 0; i < strlen(buf); i++) {
        print(buf[i]);
    }
    return strlen(buf);
}

size_t LiquidCrystal_I2C::print(long arg1, int base)
{
    // TBD
    return 0;
}

size_t LiquidCrystal_I2C::print(unsigned long arg1, int base)
{
    // TBD
    return 0;
}

size_t LiquidCrystal_I2C::print(double arg1, int base)
{
    // TBD
    return 0;
}