text: #ifndef LCD_H
  #define LCD_H
  /*************************************************************************
   Title	:   C include file for the HD44780U LCD library (lcd.c)
   Author:    Peter Fleury <pfleury@gmx.ch>  http://tinyurl.com/peterfleury
   File:	    $Id: lcd.h,v 1.14.2.4 2015/01/20 17:16:07 peter Exp $
   Software:  AVR-GCC 4.x
   Hardware:  any AVR device, memory mapped mode only for AVR with 
              memory mapped interface (AT90S8515/ATmega8515/ATmega128)
  ***************************************************************************/
  
  /**
   @mainpage
   Collection of libraries for AVR-GCC
   @author Peter Fleury pfleury@gmx.ch http://tinyurl.com/peterfleury
   @copyright (C) 2015 Peter Fleury, GNU General Public License Version 3
   
   @file
   @defgroup pfleury_lcd LCD library <lcd.h>
   @code #include <lcd.h> @endcode
   
   @brief Basic routines for interfacing a HD44780U-based character LCD display
  
   LCD character displays can be found in many devices, like espresso machines, laser printers. 
   The Hitachi HD44780 controller and its compatible controllers like Samsung KS0066U have become an industry standard for these types of displays. 
   
   This library allows easy interfacing with a HD44780 compatible display and can be
   operated in memory mapped mode (LCD_IO_MODE defined as 0 in the include file lcd.h.) or in 
   4-bit IO port mode (LCD_IO_MODE defined as 1). 8-bit IO port mode is not supported.
  
   Memory mapped mode is compatible with old Kanda STK200 starter kit, but also supports
   generation of R/W signal through A8 address line.
  
   @see The chapter <a href=" http://homepage.hispeed.ch/peterfleury/avr-lcd44780.html" target="_blank">Interfacing a HD44780 Based LCD to an AVR</a>
        on my home page, which shows example circuits how to connect an LCD to an AVR controller. 
  
   @author Peter Fleury pfleury@gmx.ch http://tinyurl.com/peterfleury
   
   @version   2.0
   
   @copyright (C) 2015 Peter Fleury, GNU General Public License Version 3
    
  */
  
  #include <inttypes.h>
  #include <avr/pgmspace.h>
  
  #define LCD_PORT         PORTD        /**< port for the LCD lines   */
  #define LCD_DATA0_PORT   PORTD     /**< port for 4bit data bit 0 */
  #define LCD_DATA1_PORT   PORTD     /**< port for 4bit data bit 1 */
  #define LCD_DATA2_PORT   PORTD     /**< port for 4bit data bit 2 */
  #define LCD_DATA3_PORT   PORTD     /**< port for 4bit data bit 3 */
  #define LCD_DATA0_PIN    2            /**< pin for 4bit data bit 0  */
  #define LCD_DATA1_PIN    3            /**< pin for 4bit data bit 1  */
  #define LCD_DATA2_PIN    4            /**< pin for 4bit data bit 2  */
  #define LCD_DATA3_PIN    5            /**< pin for 4bit data bit 3  */
  #define LCD_RS_PORT      PORTD     /**< port for RS line         */
  #define LCD_RS_PIN       0            /**< pin  for RS line         */
  #define LCD_RW_PORT      PORTD      /**< port for RW line         */
  #define LCD_RW_PIN       7           /**< pin  for RW line         */
  #define LCD_E_PORT       PORTD     /**< port for Enable line     */
  #define LCD_E_PIN        1           /**< pin  for Enable line     */
  
  #define F_CPU 1000000
  
  /**@{*/
  
  /*
   * LCD and target specific definitions below can be defined in a separate include file with name lcd_definitions.h instead modifying this file 
   * by adding -D_LCD_DEFINITIONS_FILE to the CDEFS section in the Makefile
   * All definitions added to the file lcd_definitions.h will override the default definitions from lcd.h
   */
  #ifdef _LCD_DEFINITIONS_FILE
  #include "lcd_definitions.h"
  #endif
  
  
  /**
   * @name  Definition for LCD controller type
   * Use 0 for HD44780 controller, change to 1 for displays with KS0073 controller.
   */
  #ifndef LCD_CONTROLLER_KS0073 
  #define LCD_CONTROLLER_KS0073 0  /**< Use 0 for HD44780 controller, 1 for KS0073 controller */
  #endif
  
  /** 
   * @name  Definitions for Display Size 
   * Change these definitions to adapt setting to your display
   *
   * These definitions can be defined in a separate include file \b lcd_definitions.h instead modifying this file by 
   * adding -D_LCD_DEFINITIONS_FILE to the CDEFS section in the Makefile.
   * All definitions added to the file lcd_definitions.h will override the default definitions from lcd.h
   *
   */
  #ifndef LCD_LINES
  #define LCD_LINES           2     /**< number of visible lines of the display */
  #endif
  #ifndef LCD_DISP_LENGTH
  #define LCD_DISP_LENGTH    16     /**< visibles characters per line of the display */
  #endif
  #ifndef LCD_LINE_LENGTH
  #define LCD_LINE_LENGTH  0x40     /**< internal line length of the display    */
  #endif
  #ifndef LCD_START_LINE1
  #define LCD_START_LINE1  0x00     /**< DDRAM address of first char of line 1 */
  #endif
  #ifndef LCD_START_LINE2
  #define LCD_START_LINE2  0x40     /**< DDRAM address of first char of line 2 */
  #endif
  #ifndef LCD_START_LINE3
  #define LCD_START_LINE3  0x14     /**< DDRAM address of first char of line 3 */
  #endif
  #ifndef LCD_START_LINE4
  #define LCD_START_LINE4  0x54     /**< DDRAM address of first char of line 4 */
  #endif
  #ifndef LCD_WRAP_LINES
  #define LCD_WRAP_LINES      0     /**< 0: no wrap, 1: wrap at end of visibile line */
  #endif
  
  
  /**
   * @name Definitions for 4-bit IO mode
   *
   * The four LCD data lines and the three control lines RS, RW, E can be on the 
   * same port or on different ports. 
   * Change LCD_RS_PORT, LCD_RW_PORT, LCD_E_PORT if you want the control lines on
   * different ports. 
   *
   * Normally the four data lines should be mapped to bit 0..3 on one port, but it
   * is possible to connect these data lines in different order or even on different
   * ports by adapting the LCD_DATAx_PORT and LCD_DATAx_PIN definitions.
   *
   * Adjust these definitions to your target.\n 
   * These definitions can be defined in a separate include file \b lcd_definitions.h instead modifying this file by 
   * adding \b -D_LCD_DEFINITIONS_FILE to the \b CDEFS section in the Makefile.
   * All definitions added to the file lcd_definitions.h will override the default definitions from lcd.h
   *  
   */
  #define LCD_IO_MODE      1            /**< 0: memory mapped mode, 1: IO port mode */
  
  #if LCD_IO_MODE
  
  #ifndef LCD_PORT
  #define LCD_PORT         PORTA        /**< port for the LCD lines   */
  #endif
  #ifndef LCD_DATA0_PORT
  #define LCD_DATA0_PORT   LCD_PORT     /**< port for 4bit data bit 0 */
  #endif
  #ifndef LCD_DATA1_PORT
  #define LCD_DATA1_PORT   LCD_PORT     /**< port for 4bit data bit 1 */
  #endif
  #ifndef LCD_DATA2_PORT
  #define LCD_DATA2_PORT   LCD_PORT     /**< port for 4bit data bit 2 */
  #endif
  #ifndef LCD_DATA3_PORT
  #define LCD_DATA3_PORT   LCD_PORT     /**< port for 4bit data bit 3 */
  #endif
  #ifndef LCD_DATA0_PIN
  #define LCD_DATA0_PIN    0            /**< pin for 4bit data bit 0  */
  #endif
  #ifndef LCD_DATA1_PIN
  #define LCD_DATA1_PIN    1            /**< pin for 4bit data bit 1  */
  #endif
  #ifndef LCD_DATA2_PIN
  #define LCD_DATA2_PIN    2            /**< pin for 4bit data bit 2  */
  #endif
  #ifndef LCD_DATA3_PIN
  #define LCD_DATA3_PIN    3            /**< pin for 4bit data bit 3  */
  #endif
  #ifndef LCD_RS_PORT
  #define LCD_RS_PORT      LCD_PORT     /**< port for RS line         */
  #endif
  #ifndef LCD_RS_PIN
  #define LCD_RS_PIN       4            /**< pin  for RS line         */
  #endif
  #ifndef LCD_RW_PORT
  #define LCD_RW_PORT      LCD_PORT     /**< port for RW line         */
  #endif
  #ifndef LCD_RW_PIN
  #define LCD_RW_PIN       5            /**< pin  for RW line         */
  #endif
  #ifndef LCD_E_PORT
  #define LCD_E_PORT       LCD_PORT     /**< port for Enable line     */
  #endif
  #ifndef LCD_E_PIN
  #define LCD_E_PIN        6            /**< pin  for Enable line     */
  #endif
  
  #elif defined(__AVR_AT90S4414__) || defined(__AVR_AT90S8515__) || defined(__AVR_ATmega64__) || \
        defined(__AVR_ATmega8515__)|| defined(__AVR_ATmega103__) || defined(__AVR_ATmega128__) || \
        defined(__AVR_ATmega161__) || defined(__AVR_ATmega162__)
  /*
   * memory mapped mode is only supported when the device has an external data memory interface
   */
  #define LCD_IO_DATA      0xC000    /* A15=E=1, A14=RS=1                 */
  #define LCD_IO_FUNCTION  0x8000    /* A15=E=1, A14=RS=0                 */
  #define LCD_IO_READ      0x0100    /* A8 =R/W=1 (R/W: 1=Read, 0=Write   */
  
  #else
  #error "external data memory interface not available for this device, use 4-bit IO port mode"
  
  #endif
  
  
  /**
   * @name Definitions of delays
   * Used to calculate delay timers.
   * Adapt the F_CPU define in the Makefile to the clock frequency in Hz of your target
   *
   * These delay times can be adjusted, if some displays require different delays.\n 
   * These definitions can be defined in a separate include file \b lcd_definitions.h instead modifying this file by 
   * adding \b -D_LCD_DEFINITIONS_FILE to the \b CDEFS section in the Makefile.
   * All definitions added to the file lcd_definitions.h will override the default definitions from lcd.h
   */
  #ifndef LCD_DELAY_BOOTUP
  #define LCD_DELAY_BOOTUP   16000      /**< delay in micro seconds after power-on  */
  #endif
  #ifndef LCD_DELAY_INIT
  #define LCD_DELAY_INIT      5000      /**< delay in micro seconds after initialization command sent  */
  #endif
  #ifndef LCD_DELAY_INIT_REP
  #define LCD_DELAY_INIT_REP    64      /**< delay in micro seconds after initialization command repeated */
  #endif
  #ifndef LCD_DELAY_INIT_4BIT
  #define LCD_DELAY_INIT_4BIT   64      /**< delay in micro seconds after setting 4-bit mode */ 
  #endif
  #ifndef LCD_DELAY_BUSY_FLAG
  #define LCD_DELAY_BUSY_FLAG    4      /**< time in micro seconds the address counter is updated after busy flag is cleared */
  #endif
  #ifndef LCD_DELAY_ENABLE_PULSE
  #define LCD_DELAY_ENABLE_PULSE 1      /**< enable signal pulse width in micro seconds */
  #endif
  
  
  /**
   * @name Definitions for LCD command instructions
   * The constants define the various LCD controller instructions which can be passed to the 
   * function lcd_command(), see HD44780 data sheet for a complete description.
   */
  
  /* instruction register bit positions, see HD44780U data sheet */
  #define LCD_CLR               0      /* DB0: clear display                  */
  #define LCD_HOME              1      /* DB1: return to home position        */
  #define LCD_ENTRY_MODE        2      /* DB2: set entry mode                 */
  #define LCD_ENTRY_INC         1      /*   DB1: 1=increment, 0=decrement     */
  #define LCD_ENTRY_SHIFT       0      /*   DB2: 1=display shift on           */
  #define LCD_ON                3      /* DB3: turn lcd/cursor on             */
  #define LCD_ON_DISPLAY        2      /*   DB2: turn display on              */
  #define LCD_ON_CURSOR         1      /*   DB1: turn cursor on               */
  #define LCD_ON_BLINK          0      /*     DB0: blinking cursor ?          */
  #define LCD_MOVE              4      /* DB4: move cursor/display            */
  #define LCD_MOVE_DISP         3      /*   DB3: move display (0-> cursor) ?  */
  #define LCD_MOVE_RIGHT        2      /*   DB2: move right (0-> left) ?      */
  #define LCD_FUNCTION          5      /* DB5: function set                   */
  #define LCD_FUNCTION_8BIT     4      /*   DB4: set 8BIT mode (0->4BIT mode) */
  #define LCD_FUNCTION_2LINES   3      /*   DB3: two lines (0->one line)      */
  #define LCD_FUNCTION_10DOTS   2      /*   DB2: 5x10 font (0->5x7 font)      */
  #define LCD_CGRAM             6      /* DB6: set CG RAM address             */
  #define LCD_DDRAM             7      /* DB7: set DD RAM address             */
  #define LCD_BUSY              7      /* DB7: LCD is busy                    */
  
  /* set entry mode: display shift on/off, dec/inc cursor move direction */
  #define LCD_ENTRY_DEC            0x04   /* display shift off, dec cursor move dir */
  #define LCD_ENTRY_DEC_SHIFT      0x05   /* display shift on,  dec cursor move dir */
  #define LCD_ENTRY_INC_           0x06   /* display shift off, inc cursor move dir */
  #define LCD_ENTRY_INC_SHIFT      0x07   /* display shift on,  inc cursor move dir */
  
  /* display on/off, cursor on/off, blinking char at cursor position */
  #define LCD_DISP_OFF             0x08   /* display off                            */
  #define LCD_DISP_ON              0x0C   /* display on, cursor off                 */
  #define LCD_DISP_ON_BLINK        0x0D   /* display on, cursor off, blink char     */
  #define LCD_DISP_ON_CURSOR       0x0E   /* display on, cursor on                  */
  #define LCD_DISP_ON_CURSOR_BLINK 0x0F   /* display on, cursor on, blink char      */
  
  /* move cursor/shift display */
  #define LCD_MOVE_CURSOR_LEFT     0x10   /* move cursor left  (decrement)          */
  #define LCD_MOVE_CURSOR_RIGHT    0x14   /* move cursor right (increment)          */
  #define LCD_MOVE_DISP_LEFT       0x18   /* shift display left                     */
  #define LCD_MOVE_DISP_RIGHT      0x1C   /* shift display right                    */
  
  /* function set: set interface data length and number of display lines */
  #define LCD_FUNCTION_4BIT_1LINE  0x20   /* 4-bit interface, single line, 5x7 dots */
  #define LCD_FUNCTION_4BIT_2LINES 0x28   /* 4-bit interface, dual line,   5x7 dots */
  #define LCD_FUNCTION_8BIT_1LINE  0x30   /* 8-bit interface, single line, 5x7 dots */
  #define LCD_FUNCTION_8BIT_2LINES 0x38   /* 8-bit interface, dual line,   5x7 dots */
  
  
  #define LCD_MODE_DEFAULT     ((1<<LCD_ENTRY_MODE) | (1<<LCD_ENTRY_INC) )
  
  
  
  /** 
   *  @name Functions
   */
  
  
  /**
   @brief    Initialize display and select type of cursor
   @param    dispAttr \b LCD_DISP_OFF display off\n
                      \b LCD_DISP_ON display on, cursor off\n
                      \b LCD_DISP_ON_CURSOR display on, cursor on\n
                      \b LCD_DISP_ON_CURSOR_BLINK display on, cursor on flashing             
   @return  none
  */
  extern void lcd_init(uint8_t dispAttr);
  
  
  /**
   @brief    Clear display and set cursor to home position
   @return   none
  */
  extern void lcd_clrscr(void);
  
  
  /**
   @brief    Set cursor to home position
   @return   none
  */
  extern void lcd_home(void);
  
  
  /**
   @brief    Set cursor to specified position
   
   @param    x horizontal position\n (0: left most position)
   @param    y vertical position\n   (0: first line)
   @return   none
  */
  extern void lcd_gotoxy(uint8_t x, uint8_t y);
  
  
  /**
   @brief    Display character at current cursor position
   @param    c character to be displayed                                       
   @return   none
  */
  extern void lcd_putc(char c);
  
  
  /**
   @brief    Display string without auto linefeed
   @param    s string to be displayed                                        
   @return   none
  */
  extern void lcd_puts(const char *s);
  
  
  /**
   @brief    Display string from program memory without auto linefeed
   @param    progmem_s string from program memory be be displayed                                        
   @return   none
   @see      lcd_puts_P
  */
  extern void lcd_puts_p(const char *progmem_s);
  
  
  /**
   @brief    Send LCD controller instruction command
   @param    cmd instruction to send to LCD controller, see HD44780 data sheet
   @return   none
  */
  extern void lcd_command(uint8_t cmd);
  
  
  /**
   @brief    Send data byte to LCD controller 
   
   Similar to lcd_putc(), but without interpreting LF
   @param    data byte to send to LCD controller, see HD44780 data sheet
   @return   none
  */
  extern void lcd_data(uint8_t data);
  
  
  /**
   @brief macros for automatically storing string constant in program memory
  */
  #define lcd_puts_P(__s)         lcd_puts_p(PSTR(__s))
  
  /**@}*/
  
  #endif //LCD_H
  