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
}
uint8_t LiquidCrystal_I2C::pulseEnable(uint8_t _data){
uint8_t ret;
ret = expanderWrite(_data | En); // En high
if (ret != 0) return (ret);
delayMicroseconds(1); // enable pulse must be >450ns
ret = expanderWrite(_data & ~En); // En low
delayMicroseconds(50); // commands need > 37us to settle
return ret;
}
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();
}
uint8_t LiquidCrystal_I2C::write4bits(uint8_t value) {
uint8_t ret;
ret = expanderWrite(value);
if (ret != 0) return (ret);
return pulseEnable(value);
}
void LiquidCrystal_I2C::write4bits(uint8_t value) {
expanderWrite(value);
pulseEnable(value);
}
void LiquidCrystal_I2C::backlight(void) {
_backlightval=LCD_BACKLIGHT;
expanderWrite(0);
}
void LCD_I2C::backlight(void) {
_backlightval=LCD_BACKLIGHT;
expanderWrite(0);
}
void IIClcd::write4bits(uint8_t value) {
expanderWrite(value);
pulseEnable(value);
}
void IIClcd::backlight(void) {
_backlightval = LCD_BACKLIGHT;
expanderWrite(0);
}
void PCF8574_HD44780_I2C::write4bits(uint8_t value) {
expanderWrite(value);
pulseEnable(value);
}
void PCF8574_HD44780_I2C::backlight(void) {
_backlightval=LCD_BACKLIGHT;
expanderWrite(0);
}
// Turn the (optional) backlight off/on
void TinyLiquidCrystal_I2C::noBacklight(void) {
_backlightval=LCD_NOBACKLIGHT;
expanderWrite(0);
}
void LiquidCrystal::begin() {
#if defined(__AVR_ATmega1284P__) || defined(__AVR_ATmega1284__)
if (_type == LCD_I2C) {
_displayfunction = LCD_4BITMODE | LCD_2LINE | LCD_5x8DOTS;
// 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();
}
#endif
if (_type == LCD_STD) {
_displayfunction |= LCD_2LINE;
_numlines = 2;
_currline = 0;
// 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);
// 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 it off
clear();
// Initialize to default text direction (for romance languages)
_displaymode = LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT;
// set the entry mode
command(LCD_ENTRYMODESET | _displaymode);
}
}
