#include <reg51.h>
#define LCM_Data  P1
#define Busy 0x80 //用于檢測LCM狀態字中的Busy標識

unsigned char idata HelloBuffer[]={"Hello"} ;//{0x48,0x65,0x6c,0x6c,0x6f};
sbit LCM_RW = P2^0; //定義引腳
sbit LCM_RS = P2^1;
sbit LCM_E = P2^2 ;

void WriteDataLCM(unsigned char WDLCM);
void WriteCommandLCM(unsigned char WCLCM, BusyC);
unsigned char ReadDataLCM(void);
unsigned char ReadStatusLCM(void);
void LCMInit(void);
void DisplayOneChar(unsigned char X, unsigned char Y, unsigned char idata DData);
void DisplayListChar(unsigned char X, unsigned char Y, unsigned char idata *DData);
void Delay5Ms(void);
void Delay400Ms(void);

//**********************************************寫數據
void WriteDataLCM(unsigned char WDLCM)
{
  ReadStatusLCM(); //檢測忙
  LCM_Data=WDLCM;
  LCM_RS = 1;
  LCM_RW = 0;
  LCM_E = 0; //若晶振速度太高可以在這后加小的延時
 // LCM_E = 0; //延時
  LCM_E = 1;
}

//*******************************************寫指令
void WriteCommandLCM(unsigned char WCLCM,BusyC) //BusyC為0時忽略忙檢測
{
if (BusyC) ReadStatusLCM(); //根據需要檢測忙
LCM_Data = WCLCM;
LCM_RS = 0;
LCM_RW = 0; 
LCM_E = 0;
//LCM_E = 0;
LCM_E = 1; 
}

//******************************************讀數據
unsigned char ReadDataLCM(void)
{
LCM_RS = 1; 
LCM_RW = 1;
LCM_E = 0;
//LCM_E = 0;
LCM_E = 1;
return(LCM_Data);
}

//* ****************************************讀狀態	 
unsigned char ReadStatusLCM(void)
{
LCM_Data = 0xFF; 
LCM_RS = 0;
LCM_RW = 1;
LCM_E = 0;
Delay5Ms();
LCM_E = 1;
while (LCM_Data & Busy); //檢測忙信號
return(LCM_Data);
}  
/*unsigned char ReadStatusLCM(void)
{
LCM_Data = 0xFF;
while(1)
{ 
 LCM_RS=0;
 LCM_RW = 1;
 LCM_E = 0;
 LCM_E = 0;
 LCM_E = 1;
 if(!Busy)
 break; //檢測忙信號
}
return(LCM_Data);
}	 */


void LCMInit(void) //***************************LCM初始化
{
LCM_Data = 0;
WriteCommandLCM(0x38,0); //三次顯示模式設置，不檢測忙信號
Delay5Ms();//Delay5Ms(); Delay5Ms();  
WriteCommandLCM(0x38,0);
Delay5Ms(); 
WriteCommandLCM(0x38,0);
Delay5Ms(); 

WriteCommandLCM(0x38,1); //顯示模式設置,開始要求每次檢測忙信號
WriteCommandLCM(0x08,1); //關閉顯示
WriteCommandLCM(0x01,1); //顯示清屏
WriteCommandLCM(0x06,1); // 顯示光標移動設置
WriteCommandLCM(0x0C,1); // 顯示開及光標設置
}

//**********************************************************************************按指定位置顯示一個字符
void DisplayOneChar(unsigned char X, unsigned char Y, unsigned char idata DData)
{
Y &= 0x1;
X &= 0xF; //限制X不能大于15，Y不能大于1
if (Y) X |= 0x40; //當要顯示第二行時地址碼+0x40;
X |= 0x80; //算出指令碼
WriteCommandLCM(X, 0); //這里不檢測忙信號，發送地址碼
WriteDataLCM(DData);
}

//************************************************************************************按指定位置顯示一串字符
void DisplayListChar(unsigned char X, unsigned char Y, unsigned char  idata* DData)
{
  unsigned char  ListLength;

  ListLength = 0;
  Y &= 0x1;
  X &= 0xF; //限制X不能大于15，Y不能大于1
  while (DData[ListLength]>0x20) //若到達字串尾則退出
        {
           if (X <= 0xF) //X坐標應小于0xF
              {
                DisplayOneChar(X, Y, DData[ListLength]); //顯示單個字符
                ListLength++;
                X++;
               }
         }
}

//************************************************************5ms延時
void Delay5Ms(void)
{
unsigned int TempCyc = 5552;
while(TempCyc--);
}

//************************************************************400ms延時
void Delay400Ms(void)
{
unsigned char TempCycA = 5;
unsigned int TempCycB;
while(TempCycA--)
{
TempCycB=7269;
while(TempCycB--);
};
}

void main(void)					 //采用12Mhz的時鐘脈沖
{
  P1=0;
  Delay400Ms(); //啟動等待，等LCM進入工作狀態
  LCMInit();//初始化LCD
  DisplayListChar(3,0,HelloBuffer);//啟動時的屏幕顯示“Hello”
  Delay400Ms();
 // Delay400Ms();
 // Delay400Ms();
  WriteCommandLCM(0x07,1); 
 // WriteCommandLCM(0x01,1); //顯示清屏
  while(1);
 }