text: /****************************************************************************
   Title:     HD44780U LCD library
   Author:    Peter Fleury <pfleury@gmx.ch>  http://tinyurl.com/peterfleury
   File:	    $Id: lcd.c,v 1.15.2.2 2015/01/17 12:16:05 peter Exp $
   Software:  AVR-GCC 3.3 
   Target:    any AVR device, memory mapped mode only for AT90S4414/8515/Mega
  
   DESCRIPTION
         Basic routines for interfacing a HD44780U-based text lcd display
  
         Originally based on Volker Oth's lcd library,
         changed lcd_init(), added additional constants for lcd_command(),
         added 4-bit I/O mode, improved and optimized code.
  
         Library can be operated in memory mapped mode (LCD_IO_MODE=0) or in 
         4-bit IO port mode (LCD_IO_MODE=1). 8-bit IO port mode not supported.
         
         Memory mapped mode compatible with Kanda STK200, but supports also
         generation of R/W signal through A8 address line.
  
   USAGE
         See the C include lcd.h file for a description of each function
         
  *****************************************************************************/
  #include <inttypes.h>
  #include <avr/io.h>
  #include <avr/pgmspace.h>
  #include <util/delay.h>
  #include "lcd.h"
  
  
  
  /* 
  ** constants/macros 
  */
  #define DDR(x) (*(&x - 1))      /* address of data direction register of port x */
  #if defined(__AVR_ATmega64__) || defined(__AVR_ATmega128__)
      /* on ATmega64/128 PINF is on port 0x00 and not 0x60 */
      #define PIN(x) ( &PORTF==&(x) ? _SFR_IO8(0x00) : (*(&x - 2)) )
  #else
  	#define PIN(x) (*(&x - 2))    /* address of input register of port x          */
  #endif
  
  
  #if LCD_IO_MODE
  #define lcd_e_delay()   _delay_us(LCD_DELAY_ENABLE_PULSE)
  #define lcd_e_high()    LCD_E_PORT  |=  _BV(LCD_E_PIN);
  #define lcd_e_low()     LCD_E_PORT  &= ~_BV(LCD_E_PIN);
  #define lcd_e_toggle()  toggle_e()
  #define lcd_rw_high()   LCD_RW_PORT |=  _BV(LCD_RW_PIN)
  #define lcd_rw_low()    LCD_RW_PORT &= ~_BV(LCD_RW_PIN)
  #define lcd_rs_high()   LCD_RS_PORT |=  _BV(LCD_RS_PIN)
  #define lcd_rs_low()    LCD_RS_PORT &= ~_BV(LCD_RS_PIN)
  #endif
  
  #if LCD_IO_MODE
  #if LCD_LINES==1
  #define LCD_FUNCTION_DEFAULT    LCD_FUNCTION_4BIT_1LINE 
  #else
  #define LCD_FUNCTION_DEFAULT    LCD_FUNCTION_4BIT_2LINES 
  #endif
  #else
  #if LCD_LINES==1
  #define LCD_FUNCTION_DEFAULT    LCD_FUNCTION_8BIT_1LINE
  #else
  #define LCD_FUNCTION_DEFAULT    LCD_FUNCTION_8BIT_2LINES
  #endif
  #endif
  
  #if LCD_CONTROLLER_KS0073
  #if LCD_LINES==4
  
  #define KS0073_EXTENDED_FUNCTION_REGISTER_ON  0x2C   /* |0|010|1100 4-bit mode, extension-bit RE = 1 */
  #define KS0073_EXTENDED_FUNCTION_REGISTER_OFF 0x28   /* |0|010|1000 4-bit mode, extension-bit RE = 0 */
  #define KS0073_4LINES_MODE                    0x09   /* |0|000|1001 4 lines mode */
  
  #endif
  #endif
  
  /* 
  ** function prototypes 
  */
  #if LCD_IO_MODE
  static void toggle_e(void);
  #endif
  
  /*
  ** local functions
  */
  
  
  /************************************************************************* 
  delay for a minimum of <us> microseconds
  the number of loops is calculated at compile-time from MCU clock frequency
  *************************************************************************/
  #define delay(us)  _delay_us(us) 
  
  
  #if LCD_IO_MODE
  /* toggle Enable Pin to initiate write */
  static void toggle_e(void)
  {
      lcd_e_high();
      lcd_e_delay();
      lcd_e_low();
  }
  #endif
  
  
  /*************************************************************************
  Low-level function to write byte to LCD controller
  Input:    data   byte to write to LCD
            rs     1: write data    
                   0: write instruction
  Returns:  none
  *************************************************************************/
  #if LCD_IO_MODE
  static void lcd_write(uint8_t data,uint8_t rs) 
  {
      unsigned char dataBits ;
  
  
      if (rs) {        /* write data        (RS=1, RW=0) */
         lcd_rs_high();
      } else {         /* write instruction (RS=0, RW=0) */
         lcd_rs_low();
      }
      lcd_rw_low();    /* RW=0  write mode      */
  
      if ( ( &LCD_DATA0_PORT == &LCD_DATA1_PORT) && ( &LCD_DATA1_PORT == &LCD_DATA2_PORT ) && ( &LCD_DATA2_PORT == &LCD_DATA3_PORT )
        && (LCD_DATA0_PIN == 0) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) )
      {
          /* configure data pins as output */
          DDR(LCD_DATA0_PORT) |= 0x0F;
  
          /* output high nibble first */
          dataBits = LCD_DATA0_PORT & 0xF0;
          LCD_DATA0_PORT = dataBits |((data>>4)&0x0F);
          lcd_e_toggle();
  
          /* output low nibble */
          LCD_DATA0_PORT = dataBits | (data&0x0F);
          lcd_e_toggle();
  
          /* all data pins high (inactive) */
          LCD_DATA0_PORT = dataBits | 0x0F;
      }
      else
      {
          /* configure data pins as output */
          DDR(LCD_DATA0_PORT) |= _BV(LCD_DATA0_PIN);
          DDR(LCD_DATA1_PORT) |= _BV(LCD_DATA1_PIN);
          DDR(LCD_DATA2_PORT) |= _BV(LCD_DATA2_PIN);
          DDR(LCD_DATA3_PORT) |= _BV(LCD_DATA3_PIN);
          
          /* output high nibble first */
          LCD_DATA3_PORT &= ~_BV(LCD_DATA3_PIN);
          LCD_DATA2_PORT &= ~_BV(LCD_DATA2_PIN);
          LCD_DATA1_PORT &= ~_BV(LCD_DATA1_PIN);
          LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN);
      	if(data & 0x80) LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN);
      	if(data & 0x40) LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN);
      	if(data & 0x20) LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN);
      	if(data & 0x10) LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN);   
          lcd_e_toggle();
          
          /* output low nibble */
          LCD_DATA3_PORT &= ~_BV(LCD_DATA3_PIN);
          LCD_DATA2_PORT &= ~_BV(LCD_DATA2_PIN);
          LCD_DATA1_PORT &= ~_BV(LCD_DATA1_PIN);
          LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN);
      	if(data & 0x08) LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN);
      	if(data & 0x04) LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN);
      	if(data & 0x02) LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN);
      	if(data & 0x01) LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN);
          lcd_e_toggle();        
          
          /* all data pins high (inactive) */
          LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN);
          LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN);
          LCD_DATA2_PORT |= _BV(LCD_DATA2_PIN);
          LCD_DATA3_PORT |= _BV(LCD_DATA3_PIN);
      }
  }
  #else
  #define lcd_write(d,rs) if (rs) *(volatile uint8_t*)(LCD_IO_DATA) = d; else *(volatile uint8_t*)(LCD_IO_FUNCTION) = d;
  /* rs==0 -> write instruction to LCD_IO_FUNCTION */
  /* rs==1 -> write data to LCD_IO_DATA */
  #endif
  
  
  /*************************************************************************
  Low-level function to read byte from LCD controller
  Input:    rs     1: read data    
                   0: read busy flag / address counter
  Returns:  byte read from LCD controller
  *************************************************************************/
  #if LCD_IO_MODE
  static uint8_t lcd_read(uint8_t rs) 
  {
      uint8_t data;
      
      
      if (rs)
          lcd_rs_high();                       /* RS=1: read data      */
      else
          lcd_rs_low();                        /* RS=0: read busy flag */
      lcd_rw_high();                           /* RW=1  read mode      */
      
      if ( ( &LCD_DATA0_PORT == &LCD_DATA1_PORT) && ( &LCD_DATA1_PORT == &LCD_DATA2_PORT ) && ( &LCD_DATA2_PORT == &LCD_DATA3_PORT )
        && ( LCD_DATA0_PIN == 0 )&& (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) )
      {
          DDR(LCD_DATA0_PORT) &= 0xF0;         /* configure data pins as input */
          
          lcd_e_high();
          lcd_e_delay();        
          data = PIN(LCD_DATA0_PORT) << 4;     /* read high nibble first */
          lcd_e_low();
          
          lcd_e_delay();                       /* Enable 500ns low       */
          
          lcd_e_high();
          lcd_e_delay();
          data |= PIN(LCD_DATA0_PORT)&0x0F;    /* read low nibble        */
          lcd_e_low();
      }
      else
      {
          /* configure data pins as input */
          DDR(LCD_DATA0_PORT) &= ~_BV(LCD_DATA0_PIN);
          DDR(LCD_DATA1_PORT) &= ~_BV(LCD_DATA1_PIN);
          DDR(LCD_DATA2_PORT) &= ~_BV(LCD_DATA2_PIN);
          DDR(LCD_DATA3_PORT) &= ~_BV(LCD_DATA3_PIN);
                  
          /* read high nibble first */
          lcd_e_high();
          lcd_e_delay();        
          data = 0;
          if ( PIN(LCD_DATA0_PORT) & _BV(LCD_DATA0_PIN) ) data |= 0x10;
          if ( PIN(LCD_DATA1_PORT) & _BV(LCD_DATA1_PIN) ) data |= 0x20;
          if ( PIN(LCD_DATA2_PORT) & _BV(LCD_DATA2_PIN) ) data |= 0x40;
          if ( PIN(LCD_DATA3_PORT) & _BV(LCD_DATA3_PIN) ) data |= 0x80;
          lcd_e_low();
  
          lcd_e_delay();                       /* Enable 500ns low       */
      
          /* read low nibble */    
          lcd_e_high();
          lcd_e_delay();
          if ( PIN(LCD_DATA0_PORT) & _BV(LCD_DATA0_PIN) ) data |= 0x01;
          if ( PIN(LCD_DATA1_PORT) & _BV(LCD_DATA1_PIN) ) data |= 0x02;
          if ( PIN(LCD_DATA2_PORT) & _BV(LCD_DATA2_PIN) ) data |= 0x04;
          if ( PIN(LCD_DATA3_PORT) & _BV(LCD_DATA3_PIN) ) data |= 0x08;        
          lcd_e_low();
      }
      return data;
  }
  #else
  #define lcd_read(rs) (rs) ? *(volatile uint8_t*)(LCD_IO_DATA+LCD_IO_READ) : *(volatile uint8_t*)(LCD_IO_FUNCTION+LCD_IO_READ)
  /* rs==0 -> read instruction from LCD_IO_FUNCTION */
  /* rs==1 -> read data from LCD_IO_DATA */
  #endif
  
  
  /*************************************************************************
  loops while lcd is busy, returns address counter
  *************************************************************************/
  static uint8_t lcd_waitbusy(void)
  
  {
      register uint8_t c;
      
      /* wait until busy flag is cleared */
      while ( (c=lcd_read(0)) & (1<<LCD_BUSY)) {}
      
      /* the address counter is updated 4us after the busy flag is cleared */
      delay(LCD_DELAY_BUSY_FLAG);
  
      /* now read the address counter */
      return (lcd_read(0));  // return address counter
      
  }/* lcd_waitbusy */
  
  
  /*************************************************************************
  Move cursor to the start of next line or to the first line if the cursor 
  is already on the last line.
  *************************************************************************/
  static inline void lcd_newline(uint8_t pos)
  {
      register uint8_t addressCounter;
  
  
  #if LCD_LINES==1
      addressCounter = 0;
  #endif
  #if LCD_LINES==2
      if ( pos < (LCD_START_LINE2) )
          addressCounter = LCD_START_LINE2;
      else
          addressCounter = LCD_START_LINE1;
  #endif
  #if LCD_LINES==4
  #if KS0073_4LINES_MODE
      if ( pos < LCD_START_LINE2 )
          addressCounter = LCD_START_LINE2;
      else if ( (pos >= LCD_START_LINE2) && (pos < LCD_START_LINE3) )
          addressCounter = LCD_START_LINE3;
      else if ( (pos >= LCD_START_LINE3) && (pos < LCD_START_LINE4) )
          addressCounter = LCD_START_LINE4;
      else 
          addressCounter = LCD_START_LINE1;
  #else
      if ( pos < LCD_START_LINE3 )
          addressCounter = LCD_START_LINE2;
      else if ( (pos >= LCD_START_LINE2) && (pos < LCD_START_LINE4) )
          addressCounter = LCD_START_LINE3;
      else if ( (pos >= LCD_START_LINE3) && (pos < LCD_START_LINE2) )
          addressCounter = LCD_START_LINE4;
      else 
          addressCounter = LCD_START_LINE1;
  #endif
  #endif
      lcd_command((1<<LCD_DDRAM)+addressCounter);
  
  }/* lcd_newline */
  
  
  /*
  ** PUBLIC FUNCTIONS 
  */
  
  /*************************************************************************
  Send LCD controller instruction command
  Input:   instruction to send to LCD controller, see HD44780 data sheet
  Returns: none
  *************************************************************************/
  void lcd_command(uint8_t cmd)
  {
      lcd_waitbusy();
      lcd_write(cmd,0);
  }
  
  
  /*************************************************************************
  Send data byte to LCD controller 
  Input:   data to send to LCD controller, see HD44780 data sheet
  Returns: none
  *************************************************************************/
  void lcd_data(uint8_t data)
  {
      lcd_waitbusy();
      lcd_write(data,1);
  }
  
  
  
  /*************************************************************************
  Set cursor to specified position
  Input:    x  horizontal position  (0: left most position)
            y  vertical position    (0: first line)
  Returns:  none
  *************************************************************************/
  void lcd_gotoxy(uint8_t x, uint8_t y)
  {
  #if LCD_LINES==1
      lcd_command((1<<LCD_DDRAM)+LCD_START_LINE1+x);
  #endif
  #if LCD_LINES==2
      if ( y==0 ) 
          lcd_command((1<<LCD_DDRAM)+LCD_START_LINE1+x);
      else
          lcd_command((1<<LCD_DDRAM)+LCD_START_LINE2+x);
  #endif
  #if LCD_LINES==4
      if ( y==0 )
          lcd_command((1<<LCD_DDRAM)+LCD_START_LINE1+x);
      else if ( y==1)
          lcd_command((1<<LCD_DDRAM)+LCD_START_LINE2+x);
      else if ( y==2)
          lcd_command((1<<LCD_DDRAM)+LCD_START_LINE3+x);
      else /* y==3 */
          lcd_command((1<<LCD_DDRAM)+LCD_START_LINE4+x);
  #endif
  
  }/* lcd_gotoxy */
  
  
  /*************************************************************************
  *************************************************************************/
  int lcd_getxy(void)
  {
      return lcd_waitbusy();
  }
  
  
  /*************************************************************************
  Clear display and set cursor to home position
  *************************************************************************/
  void lcd_clrscr(void)
  {
      lcd_command(1<<LCD_CLR);
  }
  
  
  /*************************************************************************
  Set cursor to home position
  *************************************************************************/
  void lcd_home(void)
  {
      lcd_command(1<<LCD_HOME);
  }
  
  
  /*************************************************************************
  Display character at current cursor position 
  Input:    character to be displayed                                       
  Returns:  none
  *************************************************************************/
  void lcd_putc(char c)
  {
      uint8_t pos;
  
  
      pos = lcd_waitbusy();   // read busy-flag and address counter
      if (c=='\n')
      {
          lcd_newline(pos);
      }
      else
      {
  #if LCD_WRAP_LINES==1
  #if LCD_LINES==1
          if ( pos == LCD_START_LINE1+LCD_DISP_LENGTH ) {
              lcd_write((1<<LCD_DDRAM)+LCD_START_LINE1,0);
          }
  #elif LCD_LINES==2
          if ( pos == LCD_START_LINE1+LCD_DISP_LENGTH ) {
              lcd_write((1<<LCD_DDRAM)+LCD_START_LINE2,0);    
          }else if ( pos == LCD_START_LINE2+LCD_DISP_LENGTH ){
              lcd_write((1<<LCD_DDRAM)+LCD_START_LINE1,0);
          }
  #elif LCD_LINES==4
          if ( pos == LCD_START_LINE1+LCD_DISP_LENGTH ) {
              lcd_write((1<<LCD_DDRAM)+LCD_START_LINE2,0);    
          }else if ( pos == LCD_START_LINE2+LCD_DISP_LENGTH ) {
              lcd_write((1<<LCD_DDRAM)+LCD_START_LINE3,0);
          }else if ( pos == LCD_START_LINE3+LCD_DISP_LENGTH ) {
              lcd_write((1<<LCD_DDRAM)+LCD_START_LINE4,0);
          }else if ( pos == LCD_START_LINE4+LCD_DISP_LENGTH ) {
              lcd_write((1<<LCD_DDRAM)+LCD_START_LINE1,0);
          }
  #endif
          lcd_waitbusy();
  #endif
          lcd_write(c, 1);
      }
  
  }/* lcd_putc */
  
  
  /*************************************************************************
  Display string without auto linefeed 
  Input:    string to be displayed
  Returns:  none
  *************************************************************************/
  void lcd_puts(const char *s)
  /* print string on lcd (no auto linefeed) */
  {
      register char c;
  
      while ( (c = *s++) ) {
          lcd_putc(c);
      }
  
  }/* lcd_puts */
  
  /*************************************************************************
  Display prefix of length n of string without auto linefeed 
  Input:    string to be displayed
  Input:    length of string to be displayed
  Returns:  none
  *************************************************************************/
  void lcd_nputs(const char *s, const int n)
  /* print string on lcd (no auto linefeed) */
  {
  
      for(int i=0;i<n;++i) {
          if(s[i] == '\0') return;
          lcd_putc(s[i]);
      }
  
  }/* lcd_nputs */
  
  
  /*************************************************************************
  Display string from program memory without auto linefeed 
  Input:     string from program memory be be displayed                                        
  Returns:   none
  *************************************************************************/
  void lcd_puts_p(const char *progmem_s)
  /* print string from program memory on lcd (no auto linefeed) */
  {
      register char c;
  
      while ( (c = pgm_read_byte(progmem_s++)) ) {
          lcd_putc(c);
      }
  
  }/* lcd_puts_p */
  
  
  /*************************************************************************
  Initialize display and select type of cursor 
  Input:    dispAttr LCD_DISP_OFF            display off
                     LCD_DISP_ON             display on, cursor off
                     LCD_DISP_ON_CURSOR      display on, cursor on
                     LCD_DISP_CURSOR_BLINK   display on, cursor on flashing
  Returns:  none
  *************************************************************************/
  void lcd_init(uint8_t dispAttr)
  {
  #if LCD_IO_MODE
      /*
       *  Initialize LCD to 4 bit I/O mode
       */
       
      if ( ( &LCD_DATA0_PORT == &LCD_DATA1_PORT) && ( &LCD_DATA1_PORT == &LCD_DATA2_PORT ) && ( &LCD_DATA2_PORT == &LCD_DATA3_PORT )
        && ( &LCD_RS_PORT == &LCD_DATA0_PORT) && ( &LCD_RW_PORT == &LCD_DATA0_PORT) && (&LCD_E_PORT == &LCD_DATA0_PORT)
        && (LCD_DATA0_PIN == 0 ) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) 
        && (LCD_RS_PIN == 4 ) && (LCD_RW_PIN == 5) && (LCD_E_PIN == 6 ) )
      {
          /* configure all port bits as output (all LCD lines on same port) */
          DDR(LCD_DATA0_PORT) |= 0x7F;
      }
      else if ( ( &LCD_DATA0_PORT == &LCD_DATA1_PORT) && ( &LCD_DATA1_PORT == &LCD_DATA2_PORT ) && ( &LCD_DATA2_PORT == &LCD_DATA3_PORT )
             && (LCD_DATA0_PIN == 0 ) && (LCD_DATA1_PIN == 1) && (LCD_DATA2_PIN == 2) && (LCD_DATA3_PIN == 3) )
      {
          /* configure all port bits as output (all LCD data lines on same port, but control lines on different ports) */
          DDR(LCD_DATA0_PORT) |= 0x0F;
          DDR(LCD_RS_PORT)    |= _BV(LCD_RS_PIN);
          DDR(LCD_RW_PORT)    |= _BV(LCD_RW_PIN);
          DDR(LCD_E_PORT)     |= _BV(LCD_E_PIN);
      }
      else
      {
          /* configure all port bits as output (LCD data and control lines on different ports */
          DDR(LCD_RS_PORT)    |= _BV(LCD_RS_PIN);
          DDR(LCD_RW_PORT)    |= _BV(LCD_RW_PIN);
          DDR(LCD_E_PORT)     |= _BV(LCD_E_PIN);
          DDR(LCD_DATA0_PORT) |= _BV(LCD_DATA0_PIN);
          DDR(LCD_DATA1_PORT) |= _BV(LCD_DATA1_PIN);
          DDR(LCD_DATA2_PORT) |= _BV(LCD_DATA2_PIN);
          DDR(LCD_DATA3_PORT) |= _BV(LCD_DATA3_PIN);
      }
      delay(LCD_DELAY_BOOTUP);             /* wait 16ms or more after power-on       */
      
      /* initial write to lcd is 8bit */
      LCD_DATA1_PORT |= _BV(LCD_DATA1_PIN);    // LCD_FUNCTION>>4;
      LCD_DATA0_PORT |= _BV(LCD_DATA0_PIN);    // LCD_FUNCTION_8BIT>>4;
      lcd_e_toggle();
      delay(LCD_DELAY_INIT);               /* delay, busy flag can't be checked here */
     
      /* repeat last command */ 
      lcd_e_toggle();      
      delay(LCD_DELAY_INIT_REP);           /* delay, busy flag can't be checked here */
      
      /* repeat last command a third time */
      lcd_e_toggle();      
      delay(LCD_DELAY_INIT_REP);           /* delay, busy flag can't be checked here */
  
      /* now configure for 4bit mode */
      LCD_DATA0_PORT &= ~_BV(LCD_DATA0_PIN);   // LCD_FUNCTION_4BIT_1LINE>>4
      lcd_e_toggle();
      delay(LCD_DELAY_INIT_4BIT);          /* some displays need this additional delay */
      
      /* from now the LCD only accepts 4 bit I/O, we can use lcd_command() */    
  #else
      /*
       * Initialize LCD to 8 bit memory mapped mode
       */
      
      /* enable external SRAM (memory mapped lcd) and one wait state */        
      MCUCR = _BV(SRE) | _BV(SRW);
  
      /* reset LCD */
      delay(LCD_DELAY_BOOTUP);                    /* wait 16ms after power-on     */
      lcd_write(LCD_FUNCTION_8BIT_1LINE,0);   /* function set: 8bit interface */                   
      delay(LCD_DELAY_INIT);                      /* wait 5ms                     */
      lcd_write(LCD_FUNCTION_8BIT_1LINE,0);   /* function set: 8bit interface */                 
      delay(LCD_DELAY_INIT_REP);                  /* wait 64us                    */
      lcd_write(LCD_FUNCTION_8BIT_1LINE,0);   /* function set: 8bit interface */                
      delay(LCD_DELAY_INIT_REP);                  /* wait 64us                    */
  #endif
  
  #if KS0073_4LINES_MODE
      /* Display with KS0073 controller requires special commands for enabling 4 line mode */
  	lcd_command(KS0073_EXTENDED_FUNCTION_REGISTER_ON);
  	lcd_command(KS0073_4LINES_MODE);
  	lcd_command(KS0073_EXTENDED_FUNCTION_REGISTER_OFF);
  #else
      lcd_command(LCD_FUNCTION_DEFAULT);      /* function set: display lines  */
  #endif
      lcd_command(LCD_DISP_OFF);              /* display off                  */
      lcd_clrscr();                           /* display clear                */ 
      lcd_command(LCD_MODE_DEFAULT);          /* set entry mode               */
      lcd_command(dispAttr);                  /* display/cursor control       */
  
  }/* lcd_init */
  