transplanted from the original URL : https://github.com/adafruit/Adafruit-RGB-LCD-Shield-Library
Diff: Adafruit_I2C_LCD.cpp
- Revision:
- 0:4f1c764a42d3
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Adafruit_I2C_LCD.cpp Mon Nov 19 09:44:37 2018 +0000 @@ -0,0 +1,401 @@ +/*************************************************** + This is a library for the Adafruit RGB 16x2 LCD Shield + Pick one up at the Adafruit shop! + ---------> http://http://www.adafruit.com/products/714 + + The shield uses I2C to communicate, 2 pins are required to + interface + Adafruit invests time and resources providing this open source code, + please support Adafruit and open-source hardware by purchasing + products from Adafruit! + + Written by Limor Fried/Ladyada for Adafruit Industries. + BSD license, all text above must be included in any redistribution + ****************************************************/ + + +#include "Adafruit_I2C_LCD.h" + +#include <stdio.h> +#include <string.h> +#include <inttypes.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 +// RGBLCDShield constructor is called). + +Adafruit_I2C_LCD::Adafruit_I2C_LCD(I2C *master, uint8_t cols, uint8_t lines, uint8_t dotsize) +{ + _i2c = new Adafruit_MCP23017(master); + _displayfunction = LCD_4BITMODE | LCD_1LINE | LCD_5x8DOTS; + + // the I/O expander pinout + _rs_pin = 15; + _rw_pin = 14; + _enable_pin = 13; + _data_pins[0] = 12; // really d4 + _data_pins[1] = 11; // really d5 + _data_pins[2] = 10; // really d6 + _data_pins[3] = 9; // really d7 + + _button_pins[0] = 0; + _button_pins[1] = 1; + _button_pins[2] = 2; + _button_pins[3] = 3; + _button_pins[4] = 4; + + begin(cols, lines, dotsize); +} + +Adafruit_I2C_LCD::~Adafruit_I2C_LCD() +{ + delete _i2c; +} + +/********** high level commands, for the user! */ +void Adafruit_I2C_LCD::clear() +{ + command(LCD_CLEARDISPLAY); // clear display, set cursor position to zero + wait_us(2000); // this command takes a long time! +} + +void Adafruit_I2C_LCD::home() +{ + command(LCD_RETURNHOME); // set cursor position to zero + wait_us(2000); // this command takes a long time! +} + +void Adafruit_I2C_LCD::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 Adafruit_I2C_LCD::noDisplay() +{ + _displaycontrol &= ~LCD_DISPLAYON; + command(LCD_DISPLAYCONTROL | _displaycontrol); +} +void Adafruit_I2C_LCD::display() +{ + _displaycontrol |= LCD_DISPLAYON; + command(LCD_DISPLAYCONTROL | _displaycontrol); +} + +// Turns the underline cursor on/off +void Adafruit_I2C_LCD::noCursor() +{ + _displaycontrol &= ~LCD_CURSORON; + command(LCD_DISPLAYCONTROL | _displaycontrol); +} +void Adafruit_I2C_LCD::cursor() +{ + _displaycontrol |= LCD_CURSORON; + command(LCD_DISPLAYCONTROL | _displaycontrol); +} + +// Turn on and off the blinking cursor +void Adafruit_I2C_LCD::noBlink() +{ + _displaycontrol &= ~LCD_BLINKON; + command(LCD_DISPLAYCONTROL | _displaycontrol); +} +void Adafruit_I2C_LCD::blink() +{ + _displaycontrol |= LCD_BLINKON; + command(LCD_DISPLAYCONTROL | _displaycontrol); +} + +// These commands scroll the display without changing the RAM +void Adafruit_I2C_LCD::scrollDisplayLeft(void) +{ + command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVELEFT); +} +void Adafruit_I2C_LCD::scrollDisplayRight(void) +{ + command(LCD_CURSORSHIFT | LCD_DISPLAYMOVE | LCD_MOVERIGHT); +} + +// This is for text that flows Left to Right +void Adafruit_I2C_LCD::leftToRight(void) +{ + _displaymode |= LCD_ENTRYLEFT; + command(LCD_ENTRYMODESET | _displaymode); +} + +// This is for text that flows Right to Left +void Adafruit_I2C_LCD::rightToLeft(void) +{ + _displaymode &= ~LCD_ENTRYLEFT; + command(LCD_ENTRYMODESET | _displaymode); +} + +// This will 'right justify' text from the cursor +void Adafruit_I2C_LCD::autoscroll(void) +{ + _displaymode |= LCD_ENTRYSHIFTINCREMENT; + command(LCD_ENTRYMODESET | _displaymode); +} + +// This will 'left justify' text from the cursor +void Adafruit_I2C_LCD::noAutoscroll(void) +{ + _displaymode &= ~LCD_ENTRYSHIFTINCREMENT; + command(LCD_ENTRYMODESET | _displaymode); +} + +// Allows us to fill the first 8 CGRAM locations +// with custom characters +void Adafruit_I2C_LCD::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]); + } + command(LCD_SETDDRAMADDR); // unfortunately resets the location to 0,0 +} + +/*********** mid level commands, for sending data/cmds */ + +void Adafruit_I2C_LCD::command(uint8_t value) +{ + send(value, LOW); +} + + +void Adafruit_I2C_LCD::write(uint8_t value) +{ + send(value, HIGH); +} + +void Adafruit_I2C_LCD::print(char *array, size_t array_size) +{ + for(size_t i = 0; i < array_size; i++){ + if(array[i] == '\0') + break; + send(array[i], HIGH); + } +} + +/************ low level data pushing commands **********/ + +// little wrapper for i/o writes +void Adafruit_I2C_LCD::_digitalWrite(uint8_t p, uint8_t d) +{ + _i2c->digitalWrite(p, d); +} + +// Allows to set the backlight, if the LCD backpack is used +void Adafruit_I2C_LCD::setBacklight(uint8_t status) +{ + // check if i2c or SPI + _i2c->digitalWrite(8, ~(status >> 2) & 0x1); + _i2c->digitalWrite(7, ~(status >> 1) & 0x1); + _i2c->digitalWrite(6, ~status & 0x1); +} + +// little wrapper for i/o directions +void Adafruit_I2C_LCD::_pinMode(uint8_t p, uint8_t d) +{ + _i2c->pinMode(p, d); +} + +void Adafruit_I2C_LCD::begin(uint8_t cols, uint8_t lines, uint8_t dotsize) +{ + _i2c->pinMode(8, OUTPUT); + _i2c->pinMode(6, OUTPUT); + _i2c->pinMode(7, OUTPUT); + setBacklight(0x7); + + if (_rw_pin) + _i2c->pinMode(_rw_pin, OUTPUT); + + _i2c->pinMode(_rs_pin, OUTPUT); + _i2c->pinMode(_enable_pin, OUTPUT); + for (uint8_t i=0; i<4; i++) + _i2c->pinMode(_data_pins[i], OUTPUT); + + for (uint8_t i=0; i<5; i++) { + _i2c->pinMode(_button_pins[i], INPUT); + _i2c->pullUp(_button_pins[i], 1); + } + + if (lines > 1) { + _displayfunction |= LCD_2LINE; + } + _numlines = lines; + _currline = 0; + + // 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 + wait_us(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); + wait_us(4500); // wait min 4.1ms + + // second try + write4bits(0x03); + wait_us(4500); // wait min 4.1ms + + // third go! + write4bits(0x03); + wait_us(150); + + // finally, set to 8-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); + wait_us(4500); // wait more than 4.1ms + + // second try + command(LCD_FUNCTIONSET | _displayfunction); + wait_us(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); + +} + +// write either command or data, with automatic 4/8-bit selection +void Adafruit_I2C_LCD::send(uint8_t value, uint8_t mode) +{ + _digitalWrite(_rs_pin, mode); + + // if there is a RW pin indicated, set it low to Write + if (_rw_pin != 255) { + _digitalWrite(_rw_pin, LOW); + } + + if (_displayfunction & LCD_8BITMODE) { + write8bits(value); + } else { + write4bits(value>>4); + write4bits(value); + } +} + +void Adafruit_I2C_LCD::pulseEnable(void) +{ + _digitalWrite(_enable_pin, LOW); + wait_us(1); + _digitalWrite(_enable_pin, HIGH); + wait_us(1); // enable pulse must be >450ns + _digitalWrite(_enable_pin, LOW); + wait_us(100); // commands need > 37us to settle +} + +void Adafruit_I2C_LCD::write4bits(uint8_t value) +{ + //if (_i2cAddr != 255) { + uint16_t out = 0; + + out = _i2c->readGPIOAB(); + + // speed up for i2c since its sluggish + for (int i = 0; i < 4; i++) { + out &= ~(1 << _data_pins[i]); + out |= ((value >> i) & 0x1) << _data_pins[i]; + } + + // make sure enable is low + out &= ~(1 << _enable_pin); + + _i2c->writeGPIOAB(out); + + // pulse enable + wait_us(1); + out |= (1 << _enable_pin); + _i2c->writeGPIOAB(out); + wait_us(1); + out &= ~(1 << _enable_pin); + _i2c->writeGPIOAB(out); + wait_us(100); + + //} else { + //for (int i = 0; i < 4; i++) { + // _pinMode(_data_pins[i], OUTPUT); + // _digitalWrite(_data_pins[i], (value >> i) & 0x01); + //} + //pulseEnable(); + //} +} + +void Adafruit_I2C_LCD::write8bits(uint8_t value) +{ + for (int i = 0; i < 8; i++) { + _pinMode(_data_pins[i], OUTPUT); + _digitalWrite(_data_pins[i], (value >> i) & 0x01); + } + + pulseEnable(); +} + +uint8_t Adafruit_I2C_LCD::readButtons(void) +{ + uint8_t reply = 0x1F; + + for (uint8_t i=0; i<5; i++) { + reply &= ~((_i2c->digitalRead(_button_pins[i])) << i); + } + return reply; +} +