#include "LiquidCrystal_I2C.h" #include #include #include // 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, uint8_t charsize) { _addr = lcd_addr; _cols = lcd_cols; _rows = lcd_rows; _charsize = charsize; _backlightval = LCD_BACKLIGHT; } void LiquidCrystal_I2C::begin() { Wire.begin(); _displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS; if (_rows > 1) { _displayfunction |= LCD_2LINE; } // for some 1 line displays you can select a 10 pixel high font if ((_charsize != 0) && (_rows == 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(); } /********** 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 > _rows) { row = _rows-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); } bool LiquidCrystal_I2C::getBacklight() { return _backlightval == LCD_BACKLIGHT; } /*********** mid level commands, for sending data/cmds */ inline void LiquidCrystal_I2C::command(uint8_t value) { send(value, 0); } inline size_t LiquidCrystal_I2C::write(uint8_t value) { send(value, Rs); return 1; } /************ 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){ Wire.beginTransmission(_addr); Wire.write((int)(_data) | _backlightval); Wire.endTransmission(); } 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 } 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); }