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/* Copyright 2009-2011 Oleg Mazurov, Circuits At Home, http://www.circuitsathome.com */

//this code is heavily borrowed from official Arduino source v.0017

// link to original http://code.google.com/p/arduino/source/browse/trunk/hardware/libraries/LiquidCrystal/LiquidCrystal.cpp

#include "Max_LCD.h"

#include "Max3421e.h"

#include <stdio.h>

#include <string.h>

#include <inttypes.h>

#include "WProgram.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 it's in that state when a sketch starts

// pin definition and set/clear

#define RS  0x04    // RS pin

#define E   0x08    // E pin

#define SET_RS  lcdPins |= RS

#define CLR_RS  lcdPins &= ~RS

#define SET_E   lcdPins |= E

#define CLR_E   lcdPins &= ~E

#define SENDlcdPins()   MAX3421E::gpioWr( lcdPins )

#define LCD_sendcmd(a)  {   CLR_RS;             \

                            sendbyte(a);    \

                        }

#define LCD_sendchar(a) {   SET_RS;             \

                            sendbyte(a);    \

                        }

static byte lcdPins;    //copy of LCD pins

Max_LCD::Max_LCD()

{

    lcdPins = 0;

}

void Max_LCD::init()

{

    _displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS;

 //   MAX3421E::gpioWr(0x55);

  begin(16, 1);  

}

void Max_LCD::begin(uint8_t cols, uint8_t lines, uint8_t dotsize) {

  if (lines > 1) {

    _displayfunction |= LCD_2LINE;

  }

  _numlines = lines;

  _currline = 0;

  // 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

  delayMicroseconds(50000);

  lcdPins = 0x30;

  SET_E;

  SENDlcdPins();

  CLR_E;

  SENDlcdPins();

  delayMicroseconds(10000); // wait min 4.1ms

  //second try

  SET_E;

  SENDlcdPins();

  CLR_E;

  SENDlcdPins();

  delayMicroseconds(10000); // wait min 4.1ms

  // third go!

  SET_E;

  SENDlcdPins();

  CLR_E;

  SENDlcdPins();

  delayMicroseconds(10000);

  // finally, set to 4-bit interface

    lcdPins = 0x20;

    //SET_RS;

    SET_E;

    SENDlcdPins();

    //CLR_RS;

    CLR_E;

    SENDlcdPins();

    delayMicroseconds(10000);

  // finally, 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 romance languages)

  _displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;

  // set the entry mode

  command(LCD_ENTRYMODESET | _displaymode);

}

/********** high level commands, for the user! */

void Max_LCD::clear()

{

  command(LCD_CLEARDISPLAY);  // clear display, set cursor position to zero

  delayMicroseconds(2000);  // this command takes a long time!

}

void Max_LCD::home()

{

  command(LCD_RETURNHOME);  // set cursor position to zero

  delayMicroseconds(2000);  // this command takes a long time!

}

void Max_LCD::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 Max_LCD::noDisplay() {

  _displaycontrol &= ~LCD_DISPLAYON;

  command(LCD_DISPLAYCONTROL | _displaycontrol);

}

void Max_LCD::display() {

  _displaycontrol |= LCD_DISPLAYON;

  command(LCD_DISPLAYCONTROL | _displaycontrol);

}

// Turns the underline cursor on/off

void Max_LCD::noCursor() {

  _displaycontrol &= ~LCD_CURSORON;

  command(LCD_DISPLAYCONTROL | _displaycontrol);

}

void Max_LCD::cursor() {

  _displaycontrol |= LCD_CURSORON;

  command(LCD_DISPLAYCONTROL | _displaycontrol);

}

// Turn on and off the blinking cursor

void Max_LCD::noBlink() {

  _displaycontrol &= ~LCD_BLINKON;

  command(LCD_DISPLAYCONTROL | _displaycontrol);

}

void Max_LCD::blink() {

  _displaycontrol |= LCD_BLINKON;

  command(LCD_DISPLAYCONTROL | _displaycontrol);

}

// These commands scroll the display without changing the RAM

void Max_LCD::scrollDisplayLeft(void) {

  command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVELEFT);

}

void Max_LCD::scrollDisplayRight(void) {

  command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVERIGHT);

}

// This is for text that flows Left to Right

void Max_LCD::leftToRight(void) {

  _displaymode |= LCD_ENTRYLEFT;

  command(LCD_ENTRYMODESET | _displaymode);

}

// This is for text that flows Right to Left

void Max_LCD::rightToLeft(void) {

  _displaymode &= ~LCD_ENTRYLEFT;

  command(LCD_ENTRYMODESET | _displaymode);

}

// This will 'right justify' text from the cursor

void Max_LCD::autoscroll(void) {

  _displaymode |= LCD_ENTRYSHIFTINCREMENT;

  command(LCD_ENTRYMODESET | _displaymode);

}

// This will 'left justify' text from the cursor

void Max_LCD::noAutoscroll(void) {

  _displaymode &= ~LCD_ENTRYSHIFTINCREMENT;

  command(LCD_ENTRYMODESET | _displaymode);

}

// Allows us to fill the first 8 CGRAM locations

// with custom characters

void Max_LCD::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]);

  }

}

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

inline void Max_LCD::command(uint8_t value) {

  LCD_sendcmd(value);

  delayMicroseconds(100);

}

inline void Max_LCD::write(uint8_t value) {

  LCD_sendchar(value);

}

void Max_LCD::sendbyte( uint8_t val )

{

    lcdPins &= 0x0f;                //prepare place for the upper nibble

    lcdPins |= ( val & 0xf0 );      //copy upper nibble to LCD variable

    SET_E;                          //send

    SENDlcdPins();

    delayMicroseconds(2);  

    CLR_E;

    delayMicroseconds(2);

    SENDlcdPins();

    lcdPins &= 0x0f;                    //prepare place for the lower nibble

    lcdPins |= ( val << 4 ) & 0xf0;    //copy lower nibble to LCD variable

    SET_E;                              //send

    SENDlcdPins();  

    CLR_E;

    SENDlcdPins();

    delayMicroseconds(100);

}