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Created September 8, 2016 09:13
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/**********************************************
LiquidCrystal_I2C
last updated on 21/12/2011
Tim Starling Fix the reset bug (Thanks Tim)
www.yfrobot.com
**********************************************/
#include "LiquidCrystal_I2C_Bela.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).
inline void LiquidCrystal_I2C::write(uint8_t value)
{
send(value, Rs);
}
// conversion for sleep delays
void delay(int millis)
{
usleep(millis*1000);
}
void delayMicroseconds(int micros)
{
usleep(micros);
}
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;
}
void LiquidCrystal_I2C::init(){
init_priv();
}
void LiquidCrystal_I2C::init_priv()
{
initI2C_RW(1, _Addr, 0);
_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
delay(50);
// Now we pull both RS and R/W low to begin commands
expanderWrite(_backlightval); // reset expanderand turn backlight off (Bit 8 =1)
delay(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);
delayMicroseconds(4500); // wait min 4.1ms
// second try
write4bits(0x03 << 4);
delayMicroseconds(4500); // wait min 4.1ms
// third go!
write4bits(0x03 << 4);
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();
}
void LiquidCrystal_I2C::print(const char* text){
while (*text){
write(*text);
text++;
}
}
/********** high level commands, for the user! */
void LiquidCrystal_I2C::clear(){
command(LCD_CLEARDISPLAY);// clear display, set cursor position to zero
delayMicroseconds(2000); // this command takes a long time!
}
void LiquidCrystal_I2C::home(){
command(LCD_RETURNHOME); // set cursor position to zero
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]);
}
}
// Turn the (optional) backlight off/on
void LiquidCrystal_I2C::noBacklight(void) {
_backlightval=LCD_NOBACKLIGHT;
expanderWrite(0);
}
void LiquidCrystal_I2C::backlight(void) {
_backlightval=LCD_BACKLIGHT;
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){
uint8_t dat = _data | _backlightval;
::write(i2C_file, &dat, 1);
}
void LiquidCrystal_I2C::pulseEnable(uint8_t _data){
expanderWrite(_data | En); // En high
delayMicroseconds(1); // enable pulse must be >450ns
expanderWrite(_data & ~En); // En low
delayMicroseconds(50); // commands need > 37us to settle
}
#ifndef LiquidCrystal_I2C_Bela_h
#define LiquidCrystal_I2C_Bela_h
#include <inttypes.h>
#include <I2c.h>
#include "Utilities.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
// flags for backlight control
#define LCD_BACKLIGHT 0x08
#define LCD_NOBACKLIGHT 0x00
#define En 0x04 // Enable bit
#define Rw 0x02 // Read/Write bit
#define Rs 0x01 // Register select bit
class LiquidCrystal_I2C : public I2c
{
public:
LiquidCrystal_I2C(uint8_t lcd_Addr,uint8_t lcd_cols,uint8_t lcd_rows);
void begin(uint8_t cols, uint8_t rows, uint8_t charsize = LCD_5x8DOTS );
void init();
void clear();
void home();
void print(const char*);
void noDisplay();
void display();
void noBlink();
void blink();
void noCursor();
void cursor();
void scrollDisplayLeft();
void scrollDisplayRight();
void printLeft();
void printRight();
void leftToRight();
void rightToLeft();
void shiftIncrement();
void shiftDecrement();
void noBacklight();
void backlight();
void autoscroll();
void noAutoscroll();
void createChar(uint8_t, uint8_t[]);
void setCursor(uint8_t, uint8_t);
void write(uint8_t);
void command(uint8_t);
int readI2C() { return 0; } // Unused
private:
void init_priv();
void send(uint8_t, uint8_t);
void write4bits(uint8_t);
void expanderWrite(uint8_t);
void pulseEnable(uint8_t);
uint8_t _Addr;
uint8_t _displayfunction;
uint8_t _displaycontrol;
uint8_t _displaymode;
uint8_t _numlines;
uint8_t _cols;
uint8_t _rows;
uint8_t _backlightval;
};
#endif
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