/*-------------------------------------------
   RS----------PC2
   RW----------GND
   EN----------PC3
   D4-D7-------PC4-PC7
---------------------------------------------*/
//定義MCU與LCD的接口 
#define LCD_EN_PORT   PORTC
#define LCD_EN_DDR    DDRC
#define LCD_RS_PORT   PORTC
#define LCD_RS_DDR    DDRC
#define LCD_DATA_PORT PORTC
#define LCD_DATA_DDR  DDRC
#define LCD_DATA_PIN  PINC
#define LCD_EN        0x08   //portc3 out
#define LCD_RS        0x04   //portc2 out
#define LCD_DATA      0xf0 //portc4/5/6/7 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);
void LCD_write_data(unsigned char X,unsigned char Y,int dat);

/*------------------------------------------------------------
函數(shù): lcd1602口線初始化和液晶初始化
-------------------------------------------------------------*/
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_ms(15);
 LCD_write_char(0x28,0); //4位顯示
 delay_ms(15);
 LCD_write_char(0x0c,0); //顯示開
 delay_ms(15);
 LCD_write_char(0x01,0); //清屏
 clear();
}

/*------------------------------------------------------------
函數(shù): 設(shè)置顯示地址
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);
}
/*-------------------------------------------------------------
函數(shù): lcd1602使能
*--------------------------------------------------------------*/
void LCD_en_write(void) //液晶使能
{ 
 LCD_EN_PORT|=LCD_EN;
 delay_us(5);
 LCD_EN_PORT&=~LCD_EN;
}
/*------------------------------------------------------------
函數(shù): 寫命令或數(shù)據(jù)到lcd1602
參數(shù)：command: 0---寫數(shù)據(jù), 1---寫命令
      data: 所要寫的命令或數(shù)據(jù)
*-------------------------------------------------------------*/
void LCD_write_char(unsigned command,unsigned data) 
{
 unsigned command_temp,data_temp;
 command_temp=command;
 data_temp=data;
 delay_us(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();
 }
}
/*-------------------------------------------------------------
函數(shù): 清屏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,' ');
}
/*-------------------------------------------------------------
函數(shù): 寫字符串
參數(shù)：列---X=0~15,行---Y=0~1 寫地址
      s為所要寫的字符串
---------------------------------------------------------------*/
void LCD_write_string(unsigned char X,unsigned char Y,unsigned char *s) 
{
 LCD_set_xy(X,Y);   
 while(*s)  
 {
  LCD_write_char(0,*s);
  s++;
 }
}

/*-------------------------------------------------------------
函數(shù): 寫數(shù)字
參數(shù)：列---X=0~15,行---Y=0~1 寫地址
      dat為所要寫的數(shù)字
---------------------------------------------------------------*/
void LCD_write_data(unsigned char X,unsigned char Y,int dat)
{
 //unsigned char fuhao;
 unsigned char data[4];
 unsigned char i;
  
 /*if(dat<0)
 {
  fuhao='-';
  dat=0-dat;
 }
 else
  fuhao=' ';
 data[0]=fuhao;*/
 data[0]=dat/1000+0x30; dat%=1000;
 data[1]=dat/100+0x30;  dat%=100;
 data[2]=dat/10+0x30; 
 data[3]=dat%10+0x30; 
 
 LCD_set_xy(X,Y);
 for(i=0;i<4;i++)
  LCD_write_char(0,data[i]);
}

/*-------------------------------------------------------------
函數(shù): 寫數(shù)字
參數(shù)：列---X=0~15,行---Y=0~1 寫地址
      dat為所要寫的數(shù)字
---------------------------------------------------------------*/
/*void LCD_write_adc(unsigned char X,unsigned char Y,int dat)
{
 unsigned char data[5];
 unsigned char i;

 dat*=4.928; 
 data[0]=dat/1000+0x30; dat%=1000;
 data[1]='.';
 data[2]=dat/100+0x30;  dat%=100;
 data[3]=dat/10+0x30;   
 data[4]=dat%10+0x30; 
 
 LCD_set_xy(X,Y);
 for(i=0;i<5;i++)
  LCD_write_char(0,data[i]);
}*/