for
Dependents: LV_FGSE_Controller_Interface
TextLCD.cpp
- Committer:
- wim
- Date:
- 2013-03-02
- Revision:
- 17:652ab113bc2e
- Parent:
- 16:c276b75e6585
- Child:
- 18:bd65dc10f27f
File content as of revision 17:652ab113bc2e:
/* mbed TextLCD Library, for a 4-bit LCD based on HD44780 * Copyright (c) 2007-2010, sford, http://mbed.org * 2013, v01: WH, Added LCD types, fixed LCD address issues, added Cursor and UDCs * 2013, v02: WH, Added I2C and SPI bus interfaces * 2013, v03: WH, Added support for LCD40x4 which uses 2 controllers * 2013, v04: WH, Added support for Display On/Off, improved 4bit bootprocess * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "TextLCD.h" #include "mbed.h" /* Create a TextLCD interface for using regular mbed pins * * @param rs Instruction/data control line * @param e Enable line (clock) * @param d4-d7 Data lines for using as a 4-bit interface * @param type Sets the panel size/addressing mode (default = LCD16x2) * @param e2 Enable2 line (clock for second controller, LCD40x4 only) */ TextLCD::TextLCD(PinName rs, PinName e, PinName d4, PinName d5, PinName d6, PinName d7, LCDType type, PinName e2) : _rs(rs), _e(e), _e2(e2), _d(d4, d5, d6, d7), _cs(NC), _type(type) { _busType = _PinBus; _init(); } /* Create a TextLCD interface using an I2C PC8574 portexpander * * @param i2c I2C Bus * @param deviceAddress I2C slave address (PCF8574) * @param type Sets the panel size/addressing mode (default = LCD16x2) */ TextLCD::TextLCD(I2C *i2c, char deviceAddress, LCDType type) : _rs(NC), _e(NC), _e2(NC), _d(NC), _i2c(i2c), _cs(NC), _type(type) { _slaveAddress = deviceAddress; _busType = _I2CBus; // Init the portexpander bus _lcd_bus = D_LCD_BUS_DEF; // write the new data to the portexpander _i2c->write(_slaveAddress, &_lcd_bus, 1); _init(); } /* Create a TextLCD interface using an SPI 74595 portexpander * * @param spi SPI Bus * @param cs chip select pin (active low) * @param type Sets the panel size/addressing mode (default = LCD16x2) */ TextLCD::TextLCD(SPI *spi, PinName cs, LCDType type) : _rs(NC), _e(NC), _e2(NC), _d(NC), _spi(spi), _cs(cs), _type(type) { _busType = _SPIBus; // Setup the spi for 8 bit data, low steady state clock, // rising edge capture, with a 500KHz or 1MHz clock rate _spi->format(8,0); _spi->frequency(500000); //_spi.frequency(1000000); // Init the portexpander bus _lcd_bus = D_LCD_BUS_DEF; // write the new data to the portexpander _setCS(false); _spi->write(_lcd_bus); _setCS(true); _init(); } /* Init the LCD Controller(s) * Clear display */ void TextLCD::_init() { // Select and configure second LCD controller when needed if(_type==LCD40x4) { _ctrl=TextLCD::_LCDCtrl_1; // Select 2nd controller _initCtrl(); // Init 2nd controller // Secondary LCD controller Clearscreen _writeCommand(0x01); // cls, and set cursor to 0 wait_ms(10); // The CLS command takes 1.64 ms. // Since we are not using the Busy flag, Lets be safe and take 10 ms } // Select and configure primary LCD controller _ctrl=TextLCD::_LCDCtrl_0; // Select primary controller _initCtrl(); // Init primary controller // Primary LCD controller Clearscreen _writeCommand(0x01); // cls, and set cursor to 0 wait_ms(10); // The CLS command takes 1.64 ms. // Since we are not using the Busy flag, Lets be safe and take 10 ms } /* Init the LCD controller * 4-bit mode, number of lines, fonttype, no cursor etc * */ void TextLCD::_initCtrl() { _setRS(false); // command mode wait_ms(20); // Wait 20ms to ensure powered up #if(1) // send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus) for (int i=0; i<3; i++) { _writeNibble(0x3); wait_ms(15); // this command takes 1.64ms, so wait for it } _writeNibble(0x2); // 4-bit mode wait_us(40); // most instructions take 40us #else //Original code. Does not comply with specification and causes problems //unless used right after power-on. // send "Display Settings" 3 times (Only top nibble of 0x30 as we've got 4-bit bus) for (int i=0; i<3; i++) { _writeByte(0x3); wait_ms(15); // this command takes 1.64ms, so wait for it } _writeByte(0x2); // 4-bit mode wait_us(40); // most instructions take 40us #endif // Display is now in 4-bit mode switch (_type) { case LCD8x1: _writeCommand(0x20); // Function set 001 DL N F - - // DL=0 (4 bits bus) // N=0 (1 line) // F=0 (5x7 dots font) break; case LCD24x4: // Special mode for KS0078 _writeCommand(0x2A); // Function set 001 DL N RE DH REV // DL=0 (4 bits bus) // N=1 (Dont care for KS0078) // RE=0 (Extended Regs, special mode for KS0078) // DH=1 (Disp shift, special mode for KS0078) // REV=0 (Reverse, special mode for KS0078) _writeCommand(0x2E); // Function set 001 DL N RE DH REV // DL=0 (4 bits bus) // N=1 (Dont care for KS0078) // RE=1 (Ena Extended Regs, special mode for KS0078) // DH=1 (Disp shift, special mode for KS0078) // REV=0 (Reverse, special mode for KS0078) _writeCommand(0x09); // Ext Function set 0000 1 FW BW NW // FW=0 (5-dot font, special mode for KS0078) // BW=0 (Cur BW invert disable, special mode for KS0078) // NW=1 (4 Line, special mode for KS0078) _writeCommand(0x2A); // Function set 001 DL N RE DH REV // DL=0 (4 bits bus) // N=1 (Dont care for KS0078) // RE=0 (Dis. Extended Regs, special mode for KS0078) // DH=1 (Disp shift, special mode for KS0078) // REV=0 (Reverse, special mode for KS0078) break; // All other LCD types are initialised as 2 Line displays (including LCD40x4) default: _writeCommand(0x28); // Function set 001 DL N F - - // DL=0 (4 bits bus) // N=1 (2 lines) // F=0 (5x7 dots font, only option for 2 line display) // - (Don't care) break; } _writeCommand(0x06); // Entry Mode 0000 01 CD S // Cursor Direction and Display Shift // CD=1 (Cur incr) // S=0 (No display shift) // _writeCommand(0x0C); // Display Ctrl 0000 1 D C B // // Display On, Cursor Off, Blink Off setCursor(TextLCD::CurOff_BlkOff); setMode(TextLCD::DispOn); } // Clear the screen, Cursor home. void TextLCD::cls() { // Select and configure second LCD controller when needed if(_type==LCD40x4) { _ctrl=TextLCD::_LCDCtrl_1; // Select 2nd controller // Second LCD controller Cursor always Off _setCursorAndDisplayMode(_currentMode, TextLCD::CurOff_BlkOff); // Second LCD controller Clearscreen _writeCommand(0x01); // cls, and set cursor to 0 wait_ms(10); // The CLS command takes 1.64 ms. // Since we are not using the Busy flag, Lets be safe and take 10 ms _ctrl=TextLCD::_LCDCtrl_0; // Select primary controller } // Primary LCD controller Clearscreen _writeCommand(0x01); // cls, and set cursor to 0 wait_ms(10); // The CLS command takes 1.64 ms. // Since we are not using the Busy flag, Lets be safe and take 10 ms // Restore cursormode on primary LCD controller when needed if(_type==LCD40x4) { _setCursorAndDisplayMode(_currentMode,_currentCursor); } _row=0; // Reset Cursor location _column=0; } // Move cursor to selected row and column void TextLCD::locate(int column, int row) { // setAddress() does all the heavy lifting: // check column and row sanity, // switch controllers for LCD40x4 if needed // switch cursor for LCD40x4 if needed // set the new memory address to show cursor at correct location setAddress(column, row); } // Write a single character (Stream implementation) int TextLCD::_putc(int value) { int addr; if (value == '\n') { //No character to write //Update Cursor _column = 0; _row++; if (_row >= rows()) { _row = 0; } } else { //Character to write _writeData(value); //Update Cursor _column++; if (_column >= columns()) { _column = 0; _row++; if (_row >= rows()) { _row = 0; } } } //else //Set next memoryaddress, make sure cursor blinks at next location addr = getAddress(_column, _row); _writeCommand(0x80 | addr); return value; } // get a single character (Stream implementation) int TextLCD::_getc() { return -1; } // Set E pin (or E2 pin) // Used for mbed pins, I2C bus expander or SPI shifregister void TextLCD::_setEnable(bool value) { switch(_busType) { case _PinBus : if(_ctrl==TextLCD::_LCDCtrl_0) { if (value) _e = 1; // Set E bit else _e = 0; // Reset E bit } else { if (value) _e2 = 1; // Set E2 bit else _e2 = 0; // Reset E2 bit } break; case _I2CBus : if(_ctrl==TextLCD::_LCDCtrl_0) { if (value) _lcd_bus |= D_LCD_E; // Set E bit else _lcd_bus &= ~D_LCD_E; // Reset E bit } else { if (value) _lcd_bus |= D_LCD_E2; // Set E2 bit else _lcd_bus &= ~D_LCD_E2; // Reset E2bit } // write the new data to the I2C portexpander _i2c->write(_slaveAddress, &_lcd_bus, 1); break; case _SPIBus : if(_ctrl==TextLCD::_LCDCtrl_0) { if (value) _lcd_bus |= D_LCD_E; // Set E bit else _lcd_bus &= ~D_LCD_E; // Reset E bit } else { if (value) _lcd_bus |= D_LCD_E2; // Set E2 bit else _lcd_bus &= ~D_LCD_E2; // Reset E2 bit } // write the new data to the SPI portexpander _setCS(false); _spi->write(_lcd_bus); _setCS(true); break; } } // Set RS pin // Used for mbed pins, I2C bus expander or SPI shifregister void TextLCD::_setRS(bool value) { switch(_busType) { case _PinBus : if (value) _rs = 1; // Set RS bit else _rs = 0; // Reset RS bit break; case _I2CBus : if (value) _lcd_bus |= D_LCD_RS; // Set RS bit else _lcd_bus &= ~D_LCD_RS; // Reset RS bit // write the new data to the I2C portexpander _i2c->write(_slaveAddress, &_lcd_bus, 1); break; case _SPIBus : if (value) _lcd_bus |= D_LCD_RS; // Set RS bit else _lcd_bus &= ~D_LCD_RS; // Reset RS bit // write the new data to the SPI portexpander _setCS(false); _spi->write(_lcd_bus); _setCS(true); break; } } // Place the 4bit data on the databus // Used for mbed pins, I2C bus expander or SPI shifregister void TextLCD::_setData(int value) { int data; switch(_busType) { case _PinBus : _d = value & 0x0F; // Write Databits break; case _I2CBus : data = value & 0x0F; if (data & 0x01) _lcd_bus |= D_LCD_D4; // Set Databit else _lcd_bus &= ~D_LCD_D4; // Reset Databit if (data & 0x02) _lcd_bus |= D_LCD_D5; // Set Databit else _lcd_bus &= ~D_LCD_D5; // Reset Databit if (data & 0x04) _lcd_bus |= D_LCD_D6; // Set Databit else _lcd_bus &= ~D_LCD_D6; // Reset Databit if (data & 0x08) _lcd_bus |= D_LCD_D7; // Set Databit else _lcd_bus &= ~D_LCD_D7; // Reset Databit // write the new data to the I2C portexpander _i2c->write(_slaveAddress, &_lcd_bus, 1); break; case _SPIBus : data = value & 0x0F; if (data & 0x01) _lcd_bus |= D_LCD_D4; // Set Databit else _lcd_bus &= ~D_LCD_D4; // Reset Databit if (data & 0x02) _lcd_bus |= D_LCD_D5; // Set Databit else _lcd_bus &= ~D_LCD_D5; // Reset Databit if (data & 0x04) _lcd_bus |= D_LCD_D6; // Set Databit else _lcd_bus &= ~D_LCD_D6; // Reset Databit if (data & 0x08) _lcd_bus |= D_LCD_D7; // Set Databit else _lcd_bus &= ~D_LCD_D7; // Reset Databit // write the new data to the SPI portexpander _setCS(false); _spi->write(_lcd_bus); _setCS(true); break; } } // Set CS line. // Only used for SPI bus void TextLCD::_setCS(bool value) { if (value) { _cs = 1; // Set CS pin } else _cs = 0; // Reset CS pin } // Write a nibble using the 4-bit interface // Used for mbed pins, I2C bus expander or SPI shifregister void TextLCD::_writeNibble(int value) { // Enable is Low _setEnable(true); _setData(value & 0x0F); // Low nibble wait_us(1); // Data setup time _setEnable(false); wait_us(1); // Datahold time // Enable is Low } // Write a byte using the 4-bit interface // Used for mbed pins, I2C bus expander or SPI shifregister void TextLCD::_writeByte(int value) { // Enable is Low _setEnable(true); _setData(value >> 4); // High nibble wait_us(1); // Data setup time _setEnable(false); wait_us(1); // Data hold time _setEnable(true); _setData(value >> 0); // Low nibble wait_us(1); // Data setup time _setEnable(false); wait_us(1); // Datahold time // Enable is Low } void TextLCD::_writeCommand(int command) { _setRS(false); wait_us(1); // Data setup time for RS _writeByte(command); wait_us(40); // most instructions take 40us } void TextLCD::_writeData(int data) { _setRS(true); wait_us(1); // Data setup time for RS _writeByte(data); wait_us(40); // data writes take 40us } #if (0) // This is the original _address() method. // It is confusing since it returns the memoryaddress or-ed with the set memorycommand 0x80. // Left it in here for compatibility with older code. New applications should use getAddress() instead. // int TextLCD::_address(int column, int row) { switch (_type) { case LCD20x4: switch (row) { case 0: return 0x80 + column; case 1: return 0xc0 + column; case 2: return 0x94 + column; case 3: return 0xd4 + column; } case LCD16x2B: return 0x80 + (row * 40) + column; case LCD16x2: case LCD20x2: default: return 0x80 + (row * 0x40) + column; } } #endif // This replaces the original _address() method. // Left it in here for compatibility with older code. New applications should use getAddress() instead. int TextLCD::_address(int column, int row) { return 0x80 | getAddress(column, row); } // This is new method to return the memory address based on row, column and displaytype. // int TextLCD::getAddress(int column, int row) { switch (_type) { case LCD8x1: return 0x00 + column; case LCD16x1: // LCD16x1 is a special layout of LCD8x2 if (column<8) return 0x00 + column; else return 0x40 + (column - 8); case LCD12x4: switch (row) { case 0: return 0x00 + column; case 1: return 0x40 + column; case 2: return 0x0C + column; case 3: return 0x4C + column; } case LCD16x4: switch (row) { case 0: return 0x00 + column; case 1: return 0x40 + column; case 2: return 0x10 + column; case 3: return 0x50 + column; } case LCD20x4: switch (row) { case 0: return 0x00 + column; case 1: return 0x40 + column; case 2: return 0x14 + column; case 3: return 0x54 + column; } // Special mode for KS0078 case LCD24x4: switch (row) { case 0: return 0x00 + column; case 1: return 0x20 + column; case 2: return 0x40 + column; case 3: return 0x60 + column; } // Not sure about this one, seems wrong. case LCD16x2B: return 0x00 + (row * 40) + column; case LCD8x2: case LCD12x2: case LCD16x2: case LCD20x2: case LCD24x2: case LCD40x2: return 0x00 + (row * 0x40) + column; case LCD40x4: // LCD40x4 is a special case since it has 2 controllers // Each controller is configured as 40x2 if (row<2) { // Test to see if we need to switch between controllers if (_ctrl != _LCDCtrl_0) { // Second LCD controller Cursor Off _setCursorAndDisplayMode(_currentMode, TextLCD::CurOff_BlkOff); // Select primary controller _ctrl = _LCDCtrl_0; // Restore cursormode on primary LCD controller _setCursorAndDisplayMode(_currentMode, _currentCursor); } return 0x00 + (row * 0x40) + column; } else { // Test to see if we need to switch between controllers if (_ctrl != _LCDCtrl_1) { // Primary LCD controller Cursor Off _setCursorAndDisplayMode(_currentMode, TextLCD::CurOff_BlkOff); // Select secondary controller _ctrl = _LCDCtrl_1; // Restore cursormode on secondary LCD controller _setCursorAndDisplayMode(_currentMode, _currentCursor); } return 0x00 + ((row-2) * 0x40) + column; } // Should never get here. default: return 0x00; } } // Set row, column and update memoryaddress. // void TextLCD::setAddress(int column, int row) { // Sanity Check column if (column < 0) { _column = 0; } else if (column >= columns()) { _column = columns() - 1; } else _column = column; // Sanity Check row if (row < 0) { _row = 0; } else if (row >= rows()) { _row = rows() - 1; } else _row = row; // Compute the memory address // For LCD40x4: switch controllers if needed // switch cursor if needed int addr = getAddress(_column, _row); _writeCommand(0x80 | addr); } int TextLCD::columns() { switch (_type) { case LCD8x1: case LCD8x2: return 8; case LCD12x2: case LCD12x4: return 12; case LCD16x1: case LCD16x2: case LCD16x2B: case LCD16x4: return 16; case LCD20x2: case LCD20x4: return 20; case LCD24x2: case LCD24x4: return 24; case LCD40x2: case LCD40x4: return 40; // Should never get here. default: return 0; } } int TextLCD::rows() { switch (_type) { case LCD8x1: case LCD16x1: return 1; case LCD8x2: case LCD12x2: case LCD16x2: case LCD16x2B: case LCD20x2: case LCD24x2: case LCD40x2: return 2; case LCD12x4: case LCD16x4: case LCD20x4: case LCD24x4: case LCD40x4: return 4; // Should never get here. default: return 0; } } // Set the Cursor Mode (Cursor Off & Blink Off, Cursor On & Blink Off, Cursor Off & Blink On, Cursor On & Blink On void TextLCD::setCursor(TextLCD::LCDCursor cursorMode) { // Save new cursor mode, needed when 2 controllers are in use or when display is switched off/on _currentCursor = cursorMode; // Configure only current LCD controller _setCursorAndDisplayMode(_currentMode, _currentCursor); } // Set the Displaymode (On/Off) void TextLCD::setMode(TextLCD::LCDMode displayMode) { // Save new displayMode, needed when 2 controllers are in use or when cursor is changed _currentMode = displayMode; // Select and configure second LCD controller when needed if(_type==LCD40x4) { if (_ctrl==TextLCD::_LCDCtrl_0) { // Configure primary LCD controller _setCursorAndDisplayMode(_currentMode, _currentCursor); // Select 2nd controller _ctrl=TextLCD::_LCDCtrl_1; // Configure secondary LCD controller _setCursorAndDisplayMode(_currentMode, TextLCD::CurOff_BlkOff); // Restore current controller _ctrl=TextLCD::_LCDCtrl_0; } else { // Select primary controller _ctrl=TextLCD::_LCDCtrl_0; // Configure primary LCD controller _setCursorAndDisplayMode(_currentMode, TextLCD::CurOff_BlkOff); // Restore current controller _ctrl=TextLCD::_LCDCtrl_1; // Configure secondary LCD controller _setCursorAndDisplayMode(_currentMode, _currentCursor); } } else { // Configure primary LCD controller _setCursorAndDisplayMode(_currentMode, _currentCursor); } } // Set the Displaymode (On/Off) and Cursortype for current controller void TextLCD::_setCursorAndDisplayMode(TextLCD::LCDMode displayMode, TextLCD::LCDCursor cursorType) { // Configure current LCD controller _writeCommand(0x08 | displayMode | cursorType); } void TextLCD::setUDC(unsigned char c, char *udc_data) { // Select and configure second LCD controller when needed if(_type==LCD40x4) { _LCDCtrl current_ctrl = _ctrl; // Temp save current controller // Select primary controller _ctrl=TextLCD::_LCDCtrl_0; // Configure primary LCD controller _setUDC(c, udc_data); // Select 2nd controller _ctrl=TextLCD::_LCDCtrl_1; // Configure secondary LCD controller _setUDC(c, udc_data); // Restore current controller _ctrl=current_ctrl; } else { // Configure primary LCD controller _setUDC(c, udc_data); } } void TextLCD::_setUDC(unsigned char c, char *udc_data) { // Select CG RAM for current LCD controller _writeCommand(0x40 + ((c & 0x07) << 3)); //Set CG-RAM address, //8 sequential locations needed per UDC // Store UDC pattern for (int i=0; i<8; i++) { _writeData(*udc_data++); } //Select DD RAM again for current LCD controller int addr = getAddress(_column, _row); _writeCommand(0x80 | addr); }