/*
	main.c
	16×16 LED點陣的掃描顯示：顯示一個漢字
*/


#include <reg51.h>


//定義I/O端口
sbit STR = P1^3;	//74HC595存儲寄存器時鐘（Storage register clock）
sbit SI = P1^4;		//74HC595串行輸入信號（Serial Input）
sbit SCK = P1^5;	//74HC595移位寄存器時鐘（Shift register clock）


//定義漢字點陣數據表
code unsigned char Zimo[32] =
{
	//文字：漢，字體：Fixedsys12，大小：16×16，取模方式：縱向取模、字節正序
	0x08,0x06,0x80,0x61,0x06,0x20,0x38,0x27,0x20,0x20,0x20,0x27,0x38,0x20,0x00,0x00,
	0x20,0x20,0x7E,0x80,0x02,0x04,0x04,0x08,0xD0,0x20,0xD0,0x08,0x0C,0x06,0x04,0x00
};


/*
函數：SysInit()
功能：系統初始化
*/
void SysInit()
{
	STR = 1;
	SI = 0;
	SCK = 0;
	TMOD &= 0x0F;
	TMOD |= 0x10;
	TH1 = 0xFC;
	TL1 = 0x66;
	TR1 = 1;
	ET1 = 1;
	EA = 1;
}


/*
函數：T1INTSVC()
功能：T1中斷服務函數
*/
void T1INTSVC() interrupt 3
{
	code unsigned char Tab[] =
	{//定義掃描數據表
		0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x7F,0xBF,0xDF,0xEF,0xF7,0xFB,0xFD,0xFE,
		0x7F,0xBF,0xDF,0xEF,0xF7,0xFB,0xFD,0xFE,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF
	};
	static unsigned char n = 0;		//局部靜態變量，用于查表
	unsigned char d;		//臨時變量
	unsigned char i;		//循環變量
	unsigned char j;		//循環變量
	unsigned char buf[4];	//臨時數組，用于向74HC595發送數據
//處理定時器T1
	TR1 = 0;
	TH1 = 0xFC;
	TL1 = 0x66;
	TR1 = 1;
//查表，取得要發送的數據
	buf[0] = Tab[n];
	buf[1] = Tab[16+n];
	buf[2] = Zimo[16+n];
	buf[3] = Zimo[n];
	n++;
	n &= 0x0F;
//向74HC595發送數據
	STR = 0;
	for ( i=0; i<4; i++ )
	{
		d = buf[i];
		j = 8;
		do
		{
			SI = (bit)(d & 0x01);
			SCK = 1;
			d >>= 1;
			SCK = 0;
		} while ( --j != 0 );
	}
	STR = 1;
}


void main()
{
	SysInit();
	for (;;);
}