/*
 * Title: LCD_Routines
 * 
 * Author: Blake C. Sutton
 *
 * Description: This is a set of functions used to initialize and write to the
 * LCD screen in 4-bit mode.  The LCD uses Port B in the following port format:
 *
 * Lower nibble (Port B 0 to 3) represents the data sent (upper nibble on LCD). 
 * 
 * Bits 6, 5, and 4 represent RS RW, and E, respectively. 
 *
 * This can also be used to test your LCD to verify that you didn't burn it...
 * which if you are Blake can be a very useful thing :D
 *  
 */
 
#ifndef __LCD_ROUTINES__
#define __LCD_ROUTINES__

#include "Delay_Routines.h"

/* 8-bit unsigned integer used for passing LCD bytes
 * without parameter overhead
 */
volatile uint8_t lcd_byte;

/* 8-bit unsigned inteteger used for passing LCD output bytes
 * Without parameter overhead.  Consists of nibble + RS + RW + E bits.
 */
volatile uint8_t lcd_nibble;

/* Writes one nibble of raw information to LCD, 
 * once it has been properly encoded by write_data_byte
 * or write_control_byte.
 *
 * Parameter: lcd_nibble (global variable, 8-bit unsigned integer)
 */
void write_nibble(void);

/* Writes one control byte (clear screen, next line, etc.) in 4-bit mode.
 * This should not be used for data -- use write_data_byte.
 * 
 * Parameter: lcd_byte (global variable, 8-bit int)
 */
void write_control_byte(void);

/* Writes one byte of data (one ASCII char) to the LCD in 4-bit mode.
 * Thus the upper nibble is written, then 
 * the lower nibble. 
 * 
 * Parameter: lcd_byte (global variable, 8-bit int)
 */
void write_data_byte(void) ;

/* Clears LCD screen and returns cursor to home
 */
void clear_home(void);

/* Internal Function -- do not call this, call init_LCD()
 */
void init_lcd_ports_and_timer(void) ;

/* Initialize LCD for 4-bit mode, 2-line mode.
 * When this routine returns, LCD is ready to display
 * characters.
 */
void init_LCD(void);

/*
 * Writes out the parameter string to the LCD.
 * LCD must be initialized first.
 */
void write_string(char input[]);

/* Function that takes in an 8 bit value and displays it on the LCD
 * according to the options -- ghetto printf.
 * 
 * display_options is a string, as follows:
 * decimal -- display as base 10 integer NOT YET IMPLEMENTED
 * hex -- display as base 16 (hexadecimal) number (0xNN)
 * binary -- display as binary (XXXXXXXX )
 * char -- display as ASCII char (a, b, c, etc.)
 */
void print_byte(uint8_t value, char display_options[] );

#endif