/*實驗名稱：字符型LCD接口實驗
  功能：在LCD上顯示
	 AT89S51 DEMO
	www.mcuprog.com
  作者：http://www.mcuprog.com
        05-02-01
*/
#include <reg51.h>
sbit E=P3^5;
sbit RW=P3^6;
sbit RS=P3^7;	
typedef unsigned char uchar;
//-------------------------------------
void Delay(unsigned int t)   // delay 40us
{
 for(;t!=0;t--) ;
}
//=============================================
void SendCommandByte(unsigned char ch)
{
   RS=0;
   RW=0;
   P0=ch;
   E=1;
    Delay(1);
   E=0;
   Delay(100);  //delay 40us
}
//-------------------------------------------------------
void SendDataByte(unsigned char ch)
{  RS=1;
   RW=0;
   P0=ch;
   E=1;
       Delay(1);
   E=0;
   Delay(100); //delay 40us
}
//-------------------------------------------------
void InitLcd()
{SendCommandByte(0x30);
 SendCommandByte(0x30);
 SendCommandByte(0x30);
 SendCommandByte(0x38);	//設置工作方式
 SendCommandByte(0x0c); //顯示狀態設置
 SendCommandByte(0x01); //清屏
 SendCommandByte(0x06); //輸入方式設置
}
//=============================================
void DisplayMsg1(uchar *p)
{ 
 unsigned char count;
 SendCommandByte(0x80);  //設置DDRAM地址
 for(count=0;count<16;count++)
    {SendDataByte(*p++);
   	}
} 
//=============================================
void DisplayMsg2(uchar *p)
{ 
 unsigned char count;
 SendCommandByte(0xc0);  //設置DDRAM地址
 for(count=0;count<16;count++)
    {SendDataByte(*p++);
   	}
}
//=============================================
main()
{char msg1[16]="  AT89S51 DEMO  ";
 char msg2[16]="www.mcuprog.com ";
 InitLcd();
 DisplayMsg1(msg1);
 DisplayMsg2(msg2);
 while(1);
}