#include <iom16v.h>
#include <macros.h>
#define LCD_EN_PORT    PORTB
#define LCD_RW_PORT    PORTB
#define LCD_RS_PORT    PORTB
#define LCD_DATA_PORT  PORTB
#define LCD_DATA_DDR   DDRB
#define LCD_DATA_PIN   PINB
#define LCD_EN         0x80   //portd7        out
#define LCD_RS         0x40   //portc6        out
#define LCD_DATA       0xf0   //portb4/5/6/7   out

/*--------------------------------------------------------------------------------------------------
Public function prototypes
--------------------------------------------------------------------------------------------------*/
void LCD_init         (void);
void LCD_en_write     (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);
void delay_nus        (unsigned int n);
void delay_nms        (unsigned int n);
void LCD_init(void)       //液晶初始化
{
 DDRB|=LCD_DATA;   // 數據為輸出
 DDRB|=LCD_RS|LCD_EN;  //置位RS.EN
 delay_nms(15);
 LCD_write_char(0x28,0);  //4位顯示
 LCD_write_char(0x0c,0);  //顯示開
 LCD_write_char(0x01,0);  //清屏
}
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 ++;
      }
  }
  void LCD_set_xy( unsigned char x, unsigned char y )  //寫地址函數
  {
    unsigned char address;
    if (y == 0) address = 0x80 + x;
    else 
       address = 0xc0 + x;
    LCD_write_char( address, 0 );
  }
void LCD_en_write(void)  //液晶使能
{
  LCD_EN_PORT|=LCD_EN;
  delay_nus(1);
  LCD_EN_PORT&=~LCD_EN;
}
void LCD_write_char(unsigned command,unsigned data) // 寫數據
{
 unsigned command_temp,data_temp;
 command_temp=command;
 data_temp=data;
 delay_nus(16);
 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();
  }
}
/*void main(void)
{
     DDRA|=LCD_DATA;   // 數據為輸出
	 DDRC|=LCD_RS|LCD_EN;  //置位RS.EN
     LCD_init();
     for(;;)    //for循環
       {
	     LCD_write_char(0x01,0);
		 delay_nms(2);
         LCD_write_string(0,0,"Wellcome");
         LCD_write_string(0,1,"www.OURAVR.com!");
         delay_nms(5000);
         LCD_write_string(0,0,"happy new year!");
         LCD_write_string(0,1,"amork:everfriend");
         delay_nms(5000);
       }
}*/
   /*-----------------------------------------------------------------------
延時函數
系統時鐘：8M
-----------------------------------------------------------------------*/
void delay_1us(void)                 //1us延時函數
  {
   asm("nop");
  }

void delay_nus(unsigned int n)       //N us延時函數
  {
   unsigned int i=0;
   for (i=0;i<n;i++)
   delay_1us();
  }
  
void delay_1ms(void)                 //1ms延時函數
  {
   unsigned int i;
   for (i=0;i<1140;i++);
  }
  
void delay_nms(unsigned int n)       //N ms延時函數
  {
   unsigned int i=0;
   for (i=0;i<n;i++)
   delay_1ms();
  }