7ledshow.c

本程序利用51单片机实现对数码管的显示控制

/****************************************/
/* Copyright (c) 2004, 通信工程学院戴佳 */
/* All rights reserved.                 */
/* 作    者：戴佳                       */
/****************************************/

/* 4位8段数码管分别动态显示“1234”， */

#include "7LEDShow.h"

void main()
{
	DIGPORT = 0;						// 关闭显示
	
	TMOD = 0x01;						// T0工作方式1

	/* 2ms 定时设置 */
	time0_tmp = 65536-time0*fosc/12;
	TH0 = (time0_tmp/256);
	TL0 = (time0_tmp%256);
	
	TR0 = 1;
	ET0 = 1;
	EA = 1;
	
	digbit = 0x01;						// 从第一位数码管开始
	wordbuf[3] = 4;
	wordbuf[2] = 3;
	wordbuf[1] = 2;
	wordbuf[0] = 1;

	while(1); 
    
}

/* 定时器0中断服务子程序，定时动态扫描显示 */
void time0_int(void) interrupt 1
{
	TH0 = (time0_tmp/256);
	TL0 = (time0_tmp%256);
	display();
}


/* 根据共阴极字型编码表获取0~9，A~B字型代码 */
uchar getcode(uchar i)
{
	uchar p;
	switch (i)
	{
		case 0:	 p=0x3f;	break;			/* 0 */
		case 1:	 p=0x06;	break;			/* 1 */
		case 2:	 p=0x5B;	break;			/* 2 */
		case 3:	 p=0x4F;	break;			/* 3 */
		case 4:	 p=0x66;	break;			/* 4 */
		case 5:	 p=0x6D;	break;			/* 5 */
		case 6:	 p=0x7D;	break;			/* 6 */
		case 7:	 p=0x07;	break;			/* 7 */
		case 8:	 p=0x7F;	break;			/* 8 */
		case 9:	 p=0x67;	break;			/* 9 */
		case 10: p=0x77;	break;			/* A */
		case 11: p=0x7C;	break;			/* B */
		case 12: p=0x39;	break;			/* C */
		case 13: p=0x5E;	break;			/* D */
		case 14: p=0x79;	break;			/* E */
		case 15: p=0x71;	break;			/* F */
		default: 			break;
	}
	return(p);
}

/* 显示函数 */
void display(void)
{
	uchar i;
	switch (digbit)
	{
		case 1:	i=0;break;
		case 2:	i=1;break;
		case 4:	i=2;break;
		case 8:	i=3;break;
		default: 	break;
	}

	DIGPORT = 0;						// 关闭显示
	WORDPORT = getcode(wordbuf[i]);		// 送字型码
	DIGPORT = digbit;					// 送字位码
	
	if (digbit<0x08)
		digbit = digbit*2;
	else
	    digbit = 0x01;
}