//-----------------------------------------------------------------------------
//實驗目的:熟悉2*2鍵盤操作.插上短路環J9、J10和J21。J7短路環要斷開。按鍵后會在液晶屏上
//顯示所按下的鍵號,如按SI鍵,在液晶上顯示S1.
//-----------------------------------------------------------------------------
// Includes
//-----------------------------------------------------------------------------

#include <c8051f330.h>                
#include <INTRINS.H>
#include <stdio.h>



sbit	key1=P1^3;        
sbit	key2=P1^4;
sbit	key3=P1^5;
sbit	key4=P1^6;
int     a;
//--------------------------------
void YJ_Init(void);
void Write_CHAR(unsigned char yjchar);
unsigned char key_in(void);
//-----------------------------------------------------
void delay(void)
{
	 a=1000;
	while(a!=0)
	{
		a--;
	}
}

/*----------------------------------------------------*/
//按鍵連接到p1.3、p1.4、p1.5、P1.6,均為開漏輸出
unsigned char key_in(void)
{XBR0 =0X00;
	P1=0xff;
	if(key1==0)
	{
		key1=1;
		delay();//延時
		if(key1==0)
		{
			while(key1==0);
         	XBR0 =0X02;
			return(0x31);//返回字符"1"表示按鍵S1按下
		}
	}

	if(key2==0)
	{
		key2=1;
		delay();//延時
		if(key2==0)
		{
			while(key2==0);
				XBR0 =0X02;
				return(0x32);//返回字符"2"表示按鍵S2按下
		}
	}

	if(key3==0)
	{
		key3=1;
		delay();//延時
		if(key3==0)
		{
			while(key3==0);
				XBR0 =0X02;
				return(0x33);//返回字符"3"表示按鍵S3按下
		}
	}

	if(key4==0)
	{
		key4=1;
		delay();//延時
		if(key4==0)
		{
			while(key4==0);
				XBR0 =0X02;
				return(0x34);//返回字符"4"表示按鍵S4按下
		}
	}
	XBR0 =0X02;
	return(0);//返回0,表示沒有按鍵按下
}

//---------------------------------------------
void main(void) 
{	
	unsigned char data1;

   PCA0MD &= ~0x40; // WDTE = 0 (watchdog timer enable bit)
   OSCICN |= 0x03; // Set internal oscillator to highest
                   // setting (24500000)

   // XBR0 = 0x00; // XBAR0: Initial Reset value
  //  XBR1 = 0x40; // XBAR1: Initial Reset value
//	P1MDOUT&=~0x78;  // Output configuration for P1
   
   // YJ_Init();
   
   P0SKIP    = 0xFE;
   P1SKIP    = 0x03;
   XBR0 = 0x02;                       // Enable SMBus pins
   XBR1 = 0x40;                       // Enable crossbar and weak pull-ups

   	while(1)
	{
		data1=key_in();						//讀按鍵
		if(data1!=0)						//有按鍵按下,顯示對應的按鍵
		{
			YJ_Init();                     //LCD初始化
                                           //準備送數據
			for(a=0;a<1000;a++);
			Write_CHAR(0x53);	
			Write_CHAR(data1);		                 	//控制LCD	
			for(a=0;a<1000;a++);

		}
	}

}