// Based on the work by DFRobot upgraded by DVSProductions #include "LiquidCrystal_I2C.h" #include /*********** mid level commands, for sending data/cmds */ #define COMMAND(value) send(value, 0) #define printIIC(args) i2c->write(_Addr, args, 1) size_t LiquidCrystal_I2C::write(uint8_t value) { send(value, Rs); return 1; } inline void LiquidCrystal_I2C::command(uint8_t value) { send(value, 0); } // 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). /*! Creates a new LCD instance !*/ LiquidCrystal_I2C::LiquidCrystal_I2C(uint8_t lcd_Addr, uint8_t lcd_cols, uint8_t lcd_rows, PinName sda, PinName scl) { _Addr = lcd_Addr << 1; _cols = lcd_cols; _rows = lcd_rows; _backlightval = LCD_NOBACKLIGHT; i2c = new I2C(sda, scl); i2c->frequency(1000000); } void LiquidCrystal_I2C::init() { init_priv(); } void LiquidCrystal_I2C::init_priv() { _displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS; begin_priv(); } void LiquidCrystal_I2C::begin_priv(uint8_t dotsize) { if (_rows > 1) { _displayfunction |= LCD_2LINE; } _numlines = _rows; // for some 1 line displays you can select a 10 pixel high font if ((dotsize != 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. Nucleo can turn on way befer 4.5V so we'll wait // 50 wait_us(50000); // Now we pull both RS and R/W low to begin commands expanderWrite(_backlightval); // reset expanderand turn backlight off (Bit 8 =1) wait_us(1000000); // 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); wait_us(4100); // wait min 4.1ms // second try write4bits(0x03 << 4); wait_us(4100); // wait min 4.1ms // third go! write4bits(0x03 << 4); wait_us(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 | LCD_ENTRYLEFT | LCD_ENTRYSHIFTDECREMENT); home(); } void LiquidCrystal_I2C::begin(uint8_t cols, uint8_t lines, uint8_t dotsize) { _cols = cols; _rows = lines; begin_priv(); } /********** high level commands, for the user! */ void LiquidCrystal_I2C::clear() { COMMAND(LCD_CLEARDISPLAY); // clear display, set cursor position to zero wait_us(2000); // this command takes a long time! } void LiquidCrystal_I2C::home() { COMMAND(LCD_RETURNHOME); // set cursor position to zero wait_us(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 (uint8_t 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); } /************ 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); } char buff; inline void LiquidCrystal_I2C::expanderWrite(uint8_t _data) { buff = (_data) | _backlightval; printIIC(&buff); } void LiquidCrystal_I2C::pulseEnable(uint8_t _data) { expanderWrite(_data | En); // En high wait_us(1); // enable pulse must be >450ns expanderWrite(_data & ~En); // En low wait_us(10); // commands need > 37us to settle } // Alias functions inline void LiquidCrystal_I2C::cursor_on() { cursor(); } inline void LiquidCrystal_I2C::cursor_off() { noCursor(); } inline void LiquidCrystal_I2C::blink_on() { blink(); } inline void LiquidCrystal_I2C::blink_off() { noBlink(); } inline 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 use sketch doesn't have to be changed print(c); } // unsupported API functions void LiquidCrystal_I2C::off() { noBacklight(); } void LiquidCrystal_I2C::on() { begin_priv(); backlight(); } void LiquidCrystal_I2C::setDelay(int cmdDelay, int charDelay) {} uint8_t LiquidCrystal_I2C::status() { return 0; } uint8_t LiquidCrystal_I2C::keypad() { return 0; } uint8_t LiquidCrystal_I2C::init_bargraph(uint8_t graphtype) { return 0; } void LiquidCrystal_I2C::draw_horizontal_graph(uint8_t row, uint8_t column, uint8_t len, uint8_t pixel_col_end) { } void LiquidCrystal_I2C::draw_vertical_graph(uint8_t row, uint8_t column, uint8_t len, uint8_t pixel_row_end) { } void LiquidCrystal_I2C::setContrast(uint8_t new_val) {}