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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
//LiquidCrystal
// 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 LiquidCrystal.cpp
// 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. The original library has been reworked in such a way that
// this class implements the all methods to command an LCD based
// on the Hitachi HD44780 and compatible chipsets using the parallel port of
// the LCD (4 bit and 8 bit).
//
// The functionality provided by this class and its base class is identical
// to the original functionality of the Arduino LiquidCrystal library.
//
//
// This library is only compatible with Arduino's SDK version 1.0
//
//
// @author F. Malpartida - fmalpartida@gmail.com
// ---------------------------------------------------------------------------
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#if (ARDUINO < 100)
#include <WProgram.h>
#else
#include <Arduino.h>
#endif
#include <LiquidCrystal.h>
// STATIC helper routines
// ---------------------------------------------------------------------------
/*!
@function
@abstract waits for a given time in microseconds (compilation dependent).
@discussion Waits for a given time defined in microseconds depending on
the FAST_MODE define. If the FAST_MODE is defined the call will return
inmediatelly.
@param uSec[in] time in microseconds.
@result None
*/
inline static void waitUsec ( uint16_t uSec )
{
#ifndef FAST_MODE
delayMicroseconds ( uSec );
#endif // FAST_MODE
}
// CONSTRUCTORS
// ---------------------------------------------------------------------------
LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
{
init(LCD_8BIT, rs, rw, enable, d0, d1, d2, d3, d4, d5, d6, d7);
}
LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t enable,
uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
{
init(LCD_8BIT, rs, 255, enable, d0, d1, d2, d3, d4, d5, d6, d7);
}
LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t rw, uint8_t enable,
uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3)
{
init(LCD_4BIT, rs, rw, enable, d0, d1, d2, d3, 0, 0, 0, 0);
}
LiquidCrystal::LiquidCrystal(uint8_t rs, uint8_t enable,
uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3)
{
init(LCD_4BIT, rs, 255, enable, d0, d1, d2, d3, 0, 0, 0, 0);
}
// PRIVATE METHODS
// ---------------------------------------------------------------------------
// 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).
// A call to begin() will reinitialize the LCD.
//
// init
void LiquidCrystal::init(uint8_t fourbitmode, uint8_t rs, uint8_t rw, uint8_t enable,
uint8_t d0, uint8_t d1, uint8_t d2, uint8_t d3,
uint8_t d4, uint8_t d5, uint8_t d6, uint8_t d7)
{
uint8_t i;
// Initialize the IO pins
// -----------------------
_rs_pin = rs;
_rw_pin = rw;
_enable_pin = enable;
_data_pins[0] = d0;
_data_pins[1] = d1;
_data_pins[2] = d2;
_data_pins[3] = d3;
_data_pins[4] = d4;
_data_pins[5] = d5;
_data_pins[6] = d6;
_data_pins[7] = d7;
// Initialize the IO port direction to OUTPUT
// ------------------------------------------
for ( i = 0; i < 4; i++ )
{
pinMode ( _data_pins[i], OUTPUT );
}
// Initialize the rest of the ports if it is an 8bit controlled LCD
// ----------------------------------------------------------------
if ( !fourbitmode )
{
for ( i = 4; i < 8; i++ )
{
pinMode ( _data_pins[i], OUTPUT );
}
}
pinMode(_rs_pin, OUTPUT);
// we can save 1 pin by not using RW. Indicate by passing 255 instead of pin#
if (_rw_pin != 255)
{
pinMode(_rw_pin, OUTPUT);
}
pinMode(_enable_pin, OUTPUT);
// Initialise displaymode functions to defaults: LCD_1LINE and LCD_5x8DOTS
// -------------------------------------------------------------------------
if (fourbitmode)
_displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS;
else
_displayfunction = LCD_8BITMODE | LCD_1LINE | LCD_5x8DOTS;
}
// PUBLIC METHODS
// ---------------------------------------------------------------------------
//
// begin
void LiquidCrystal::begin(uint8_t cols, uint8_t lines, uint8_t dotsize)
{
if (lines > 1)
{
_displayfunction |= LCD_2LINE;
}
_numlines = lines;
_cols = cols;
// 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 before 4.5V so we'll wait
// 50
// ---------------------------------------------------------------------------
delayMicroseconds(50000);
// Now we pull both RS and R/W low to begin commands
digitalWrite(_rs_pin, LOW);
digitalWrite(_enable_pin, LOW);
if (_rw_pin != 255)
{
digitalWrite(_rw_pin, LOW);
}
//put the LCD into 4 bit or 8 bit mode
// -------------------------------------
if (! (_displayfunction & LCD_8BITMODE))
{
// 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);
delayMicroseconds(4500); // wait min 4.1ms
// second try
write4bits(0x03);
delayMicroseconds(4500); // wait min 4.1ms
// third go!
write4bits(0x03);
delayMicroseconds(150);
// finally, set to 4-bit interface
write4bits(0x02);
}
else
{
// this is according to the hitachi HD44780 datasheet
// page 45 figure 23
// Send function set command sequence
command(LCD_FUNCTIONSET | _displayfunction);
delayMicroseconds(4500); // wait more than 4.1ms
// second try
command(LCD_FUNCTIONSET | _displayfunction);
delayMicroseconds(150);
// third go
command(LCD_FUNCTIONSET | _displayfunction);
}
// 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 the LCD
clear();
// Initialize to default text direction (for romance languages)
_displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;
// set the entry mode
command(LCD_ENTRYMODESET | _displaymode);
}
/************ low level data pushing commands **********/
// send
void LiquidCrystal::send(uint8_t value, uint8_t mode)
{
digitalWrite( _rs_pin, mode );
// if there is a RW pin indicated, set it low to Write
// ---------------------------------------------------
if (_rw_pin != 255)
{
digitalWrite(_rw_pin, LOW);
}
if (_displayfunction & LCD_8BITMODE)
{
write8bits(value);
}
else
{
write4bits ( value >> 4 );
write4bits ( value );
}
waitUsec ( EXEC_TIME ); // wait for the command to execute by the LCD
}
//
// pulseEnable
void LiquidCrystal::pulseEnable(void)
{
// There is no need for the delays, since the digitalWrite operation
// takes longer.
digitalWrite(_enable_pin, HIGH);
waitUsec(1); // enable pulse must be > 450ns
digitalWrite(_enable_pin, LOW);
}
//
// write4bits
void LiquidCrystal::write4bits(uint8_t value)
{
for (uint8_t i = 0; i < 4; i++)
{
digitalWrite(_data_pins[i], (value >> i) & 0x01);
}
pulseEnable();
}
//
// write8bits
void LiquidCrystal::write8bits(uint8_t value)
{
for (uint8_t i = 0; i < 8; i++)
{
digitalWrite(_data_pins[i], (value >> i) & 0x01);
}
pulseEnable();
}
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