root/twiLCD/twiLCD.cpp

extern "C" {
    #include <Wire/Wire.h>
}

#include "twiLCD.h"

#ifdef TWI_LCD_DPOT_CTRL
#include "../ds1803/ds1803.h"
#endif

twiLCD::twiLCD()
{
#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
    #if defined(TWI_LCD_CTRL) && !defined(TWI_LCD_BL_PWM)
        backlightStatus = 0;
    #endif
    
    #ifdef TWI_LCD_BL_PWM
        pinMode(TWI_LCD_BACKLIGHT, HIGH);
    #endif
    
    displayStatus = false;
#endif

#ifdef WIRE_LIB_SCAN_MOD
    /*if (!Wire.isStarted())*/ Wire.begin();
#else
    Wire.begin();
#endif
}

twiLCD LCD = twiLCD();

void twiLCD::Init() {
#ifdef TWI_LCD_CTRL
    backlightOff();
#ifdef TWI_LCD_DPOT_CTRL
    setBrightness(0);
#endif
#endif
    delay(20);
/////////// 4 pin initialization
    writeCommand(0x03); // function set: 4 pin initialization
    delay(5);
    writeCommand(0x03); // function set: 4 pin initialization
    delay(1);
    writeCommand(0x03); // function set: 4 pin initialization
    delay(1);
    writeCommand(0x02); // function set: 4 pin initialization
/////////// end of 4 pin initialization 
    
    
    writeCommand(LCD_FUNCTION_SET); // function set: 4-bit interface, 1 display lines, 5x7 font
    writeCommand(LCD_ENTRY_MODE);
    writeCommand(LCD_CURSOR);
    clearScreen();
    
    writeCommand(LCD_CLOSE_INIT);
    
#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
#ifdef TWI_LCD_CTRL
    #if defined(TWI_LCD_BL_PWM) || defined(TWI_LCD_DPOT_CTRL)
        #ifdef TWI_LCD_DPOT_CTRL
            setBrightness();
        #endif
        backlightOn(TWI_LCD_BL_LEVEL);
    #else
        backlightOn();
    #endif
#endif

    displayStatus = true;
#endif
}

boolean twiLCD::checkLCDBusy(void)
{
    Wire.requestFrom(PCF8574_RADDR, 1);
    
    while (!Wire.available());
    
    return (Wire.receive() & TWI_LCD_BUSY ? true : false);
}

void twiLCD::writeCommand(uint8_t value)
{
    int value1  = 0;
    int control = 0; // stores RS and RW
        
#ifdef TWI_LCD_USE_TIMEOUT
    previousMillis  = millis();
#endif
    
    control = value >> 8;   // get the control signals RS and RW
    control >>= 5;          // shift the control signals to the left
  
    Wire.beginTransmission(PCF8574_WADDR);
    
    value1  = value;
    cbi(value1, TWI_LCD_DATAL); // Turn off LByte
    
    cbi(value1, TWI_LCD_RS);
    cbi(value1, TWI_LCD_RW);
    
    sendPulse(value1);
    
    delay(1);
    
    cbi(value, TWI_LCD_DATAH);  // Turn off HByte
    value <<= 4;
    
    cbi(value, TWI_LCD_RS);
    cbi(value, TWI_LCD_RW);
    
    sendPulse(value);
    
    Wire.endTransmission();
    
    delay(1);
}

void twiLCD::writeData(uint8_t value)
{
    int value1  = 0;
    int control = 0; // stores RS and RW
    
    // Wait for the LCD to be ready
    
#ifdef TWI_LCD_USE_TIMEOUT
    previousMillis  = millis();
#endif

    control = value >> 8;   // get the control signals RS and RW
    control >>= 5;          // shift the control signals to the left
    
    value1  = value;
    cbi(value1, TWI_LCD_DATAL); // Turn off LByte
    sbi(value1, TWI_LCD_RS);
    cbi(value1, TWI_LCD_RW);
    
    while (checkLCDBusy());
    
    Wire.beginTransmission(PCF8574_WADDR);
    sendPulse(value1);
    
    delay(1);
    
    cbi(value, TWI_LCD_DATAH);  // Turn off HByte
    value   <<= 4;
    
    sbi(value, TWI_LCD_RS);
    cbi(value, TWI_LCD_RW);
    
    sendPulse(value);
    Wire.endTransmission();
}

void twiLCD::sendPulse(int value)
{
    cbi(value, TWI_LCD_ENABLE);
    writeToPCF(value);
    
    sbi(value, TWI_LCD_ENABLE);
    writeToPCF(value);
    
    cbi(value, TWI_LCD_ENABLE);
    writeToPCF(value);
}

void twiLCD::writeToPCF(int value)
{
#if defined(TWI_LCD_CTRL) && !defined(TWI_LCD_BL_PWM)
    if (backlightStatus)
        sbi(value, TWI_LCD_BACKLIGHT);
    else
        cbi(value, TWI_LCD_BACKLIGHT);
    
    Wire.send(value);
#else
    Wire.send(value);
#endif
}

void twiLCD::clearScreen(void)
{
    writeCommand(LCD_CLEAR);
    delay(100);
    
#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
    currentLine = 1;
#endif
    
#ifdef LCD_USE_CLRSCREEN_CALLBACK
    if (twiLCDcallbackFunc[0]) twiLCDcallbackFunc[0]();
#endif
}

void twiLCD::printString_P(const char *data)
{
    int ch;
    
    for (;;) {
        ch = pgm_read_byte( data++ );
        if ( !ch ) return;
        writeData(ch);
    }
}

#if defined(__AVR_ATmega168__) && !defined(TWI_LCD_SMALL)
#ifdef TWI_LCD_USE_TIMEOUT
boolean twiLCD::checkTimeout(void)
{
    if (displayStatus && millis() - previousMillis > TWI_LCD_TIMEOUT) {
        turnOff();
        return true;
    }

    return false;
}
#endif

#ifdef TWI_LCD_CTRL
#ifdef TWI_LCD_BL_PWM
void twiLCD::backlightOn(void)
{
    digitalWrite(TWI_LCD_BACKLIGHT, HIGH);
}

void twiLCD::backlightOn(uint8_t value)
{
    analogWrite(TWI_LCD_BACKLIGHT, value);
}

void twiLCD::backlightOff(void)
{
    digitalWrite(TWI_LCD_BACKLIGHT, LOW);
}
#else
#ifdef TWI_LCD_DPOT_CTRL
void twiLCD::backlightOn(void)
{
    DPOT.setWiper2(TWI_LCD_BL_LEVEL);
}

void twiLCD::backlightOn(uint8_t value)
{
    DPOT.setWiper2(value);
}

void twiLCD::backlightOff(void)
{
    DPOT.setWiper2(0);
}

void twiLCD::setBrightness(void)
{
    DPOT.setWiper1(TWI_LCD_DB_LEVEL);
}

void twiLCD::setBrightness(uint8_t value)
{
    DPOT.setWiper1(value);
}

#else
void twiLCD::backlightOn(void)
{
    int val = 0;
    backlightStatus = 1;
    sbi(val, TWI_LCD_BACKLIGHT);
    
    Wire.beginTransmission(PCF8574_WADDR);
    Wire.send(val);
    Wire.endTransmission();
}

void twiLCD::backlightOff(void)
{
    int val = 0;
    backlightStatus = 0;
    cbi(val, TWI_LCD_BACKLIGHT);
    
    Wire.beginTransmission(PCF8574_WADDR);
    Wire.send(val);
    Wire.endTransmission();
}
#endif
#endif
#endif

void twiLCD::turnOff(void)
{
    writeCommand(LCD_TURN_OFF);
#if defined(TWI_LCD_CTRL)
    backlightOff();
#ifdef TWI_LCD_DPOT_CTRL
    setBrightness(0);
#endif
#endif
    displayStatus = false;
}

/**
 * This function needs a rewrite
**/
void twiLCD::setCursor(int index)
{
    //0-79, index for one line display, 8 bit mode
    //0-39 and 64-103 for lines one and two of two line display, not implemented yet
    int cmd = 128+index;
    writeCommand(cmd);
}

/**
 * This function needs a rewrite
**/
void twiLCD::moveToXY(uint8_t row, uint8_t column)
{
    int position;
    
    //  Determine the new position
    position = (row * 20) + column;
    
    //  Send the correct commands to the command register of the LCD
    if(position < 20)
        writeCommand(0x80 | position);
    else if(position >= 20 && position < 40)
        writeCommand(0x80 | (position % 20 + 0x40));
    else if(position >= 41 && position < 60)
        writeCommand(0x80 | (position % 40 + 0x14));
    else if(position >= 20 && position < 40)
        writeCommand(0x80 | (position % 60 + 0x54));
}

uint8_t twiLCD::getCurrentLine(void)
{
    return currentLine;
}

void twiLCD::goToLine(uint8_t line)
{
    if (line > LCD_ROWS) return;
    moveToXY(line - 1, 0);
    currentLine = line;
}

void twiLCD::goToNextLine(void)
{
    if (currentLine+1 > LCD_ROWS) {
        goToLine(1);
    } else {
        goToLine(currentLine+1);
    }
}

void twiLCD::goHome(void)
{
    writeCommand(LCD_GO_HOME);   // set cursor position to zero
    currentLine = 1;
}

void twiLCD::clearLine(void)
{
    int ii;
    moveToXY(currentLine-1, 0);
    
    for (ii=0;ii<LCD_COLUMNS;ii++)
    {
        printString(" ");
    }
    
    moveToXY(currentLine-1, 0);
}

void twiLCD::shiftDisplayLeft(void)
{ 
    writeCommand(LCD_SHIFT_LEFT);
}

void twiLCD::shiftDisplayRight(void)
{
    writeCommand(LCD_SHIFT_RIGHT);
}

bool twiLCD::getCurrentStatus(void)
{
    return displayStatus;
}

void twiLCD::printInteger(uint16_t integer, bool leadingZero)
{   
    uint8_t thousands = integer / 1000;
    uint8_t hundreds = (integer - thousands*1000) / 100;
    uint8_t tens = (integer - thousands*1000 - hundreds*100 ) / 10;
    writeData(tens + 0x30);
    
    uint8_t ones = (integer - thousands*1000 - hundreds*100 - tens*10);
    writeData(ones + 0x30);
}

void twiLCD::printInteger(int16_t integer)
{
    if (integer < 0)  {
        printString("-");
        integer = 0 - integer;
    }
    
    //  Break down the original number into the thousands, hundreds, tens,
    //  and ones places and then immediately write that value to the LCD
    uint8_t thousands = integer / 1000;
    if (thousands > 0) writeData(thousands + 0x30);
    
    uint8_t hundreds = (integer - thousands*1000) / 100;
    if (hundreds > 0 || thousands > 0)
        writeData(hundreds + 0x30);
    
    uint8_t tens = (integer - thousands*1000 - hundreds*100 ) / 10;
    if (tens || hundreds > 0 || thousands > 0)
        writeData(tens + 0x30);
    
    uint8_t ones = (integer - thousands*1000 - hundreds*100 - tens*10);
    writeData(ones + 0x30);
}

#endif

#ifdef LCD_USE_CLRSCREEN_CALLBACK
void twiLCD::clrsSetCallback(void (*userFunc)(void))
{
    twiLCDcallbackFunc[0] = userFunc;
}
#endif