#include <iom16v.h>
#include <macros.h>
#define LCD_EN_PORT    PORTA
#define LCD_EN_DDR     DDRA
#define LCD_RS_PORT    PORTA
#define LCD_RS_DDR     DDRA
#define LCD_DATA_PORT  PORTA
#define LCD_DATA_DDR   DDRA
#define LCD_DATA_PIN   PINA
#define LCD_EN         0x08   //porta3        out
#define LCD_RS         0x04   //porta2       out
#define LCD_DATA       0xf0   //porta4/5/6/7   out

/*--------------------------------------------------------------------------------------------------
Public function prototypes
--------------------------------------------------------------------------------------------------*/
void LCD_init         (void);
void LCD_en_write     (void);
void clear(void);
void LCD_write_char   (unsigned command,unsigned data);
void LCD_set_xy       (unsigned char x, unsigned char y);
void LCD_write_string (unsigned char X,unsigned char Y,unsigned char *s);
extern delay_nus        (unsigned int n);
extern delay_nms        (unsigned int n);

/*------------------------------------------------------------
function: initial the related port of 1602, set the work mode of 1602
-------------------------------------------------------------*/
void LCD_init(void)       //液晶初始化
{
 LCD_DATA_DDR|=LCD_DATA;
 LCD_EN_DDR|=LCD_EN;
 LCD_RS_DDR|=LCD_RS;
 delay_nms(15);
 LCD_write_char(0x28,0);  //4位顯示
 delay_nms(15);
 LCD_write_char(0x0c,0);  //顯示開
 delay_nms(15);
 LCD_write_char(0x01,0);  //清屏
}

/*--------------------------------------------------------------------
fuction: write string to lcd1602
para:   x--the address of a line
        y--the display line
		s--a pointer to a string
*--------------------------------------------------------------------*/
void LCD_write_string(unsigned char X,unsigned char Y,unsigned char *s)
  {
    LCD_set_xy( X, Y ); //寫地址
    
    while (*s)  // 寫顯示字符
      {
        LCD_write_char( 0, *s );
	    s ++;
      }
  }
 /*------------------------------------------------------------
 function: set the display address
 para: x---the display address of a line   limit: 0---15
       y---the display line   limit 0 or 1 
 --------------------------------------------------------------*/
 
 void LCD_set_xy( unsigned char x, unsigned char y )  //寫地址函數(shù)
  {
    unsigned char address;
    if (y == 0) address = 0x80 + x;                  //the first line
    else 
       address = 0xc0 + x;                           //the second line
    LCD_write_char( address, 0 );
  }
/*-------------------------------------------------------------
function : enable or disable the rs line of the lcd1602
*--------------------------------------------------------------*/
void LCD_en_write(void)  //液晶使能
{ 
  LCD_EN_PORT|=LCD_EN;
  delay_nus(5);
  LCD_EN_PORT&=~LCD_EN;
}
/*------------------------------------------------------------
function: write command or data to lcd1602
prar:
       command:  0---write data, 1-----write command
	   data: commad or data which you want to write
*-------------------------------------------------------------*/
void LCD_write_char(unsigned command,unsigned data) 
{
 unsigned command_temp,data_temp;
 command_temp=command;
 data_temp=data;
 delay_nus(25);
 if(command==0)
 {
  LCD_RS_PORT|=LCD_RS;  //RS=1
  LCD_DATA_PORT&=0X0f;
  LCD_DATA_PORT|=data_temp&0xf0;  //寫高四位
  LCD_en_write();
  data_temp=data_temp<<4;  
  LCD_DATA_PORT&=0X0f;
  LCD_DATA_PORT|=data_temp&0xf0;   //寫低四位
  LCD_en_write();
 }
 else
 {
  LCD_RS_PORT&=~LCD_RS;   //RS=0
  LCD_DATA_PORT&=0X0f;
  LCD_DATA_PORT|=command_temp&0xf0; //寫高四位
  LCD_en_write();
  command_temp=command_temp<<4;
  LCD_DATA_PORT&=0x0f;
  LCD_DATA_PORT|=command_temp&0xf0;  //寫低四位
  LCD_en_write();
  }
}
/*-------------------------------------------------------------
function: clear the lcd1602
---------------------------------------------------------------*/
void clear(void)
{
   unsigned char i;
   LCD_set_xy(0,0);
   for(i=0;i<16;i++)
   		LCD_write_char(0,' ');
   LCD_set_xy(0,1);
   for(i=0;i<16;i++)
   		LCD_write_char(0,' ');
}