main.c

从零开始学51单片机源代码

//main.c
#include <reg51.h>	//包含头文件

 //定义端口寄存器
sfr P0M0 = 0X93;
sfr P0M1 = 0X94;
sfr P1M0 = 0X91;
sfr P1M1 = 0X92;
sfr P2M0 = 0X95;
sfr P2M1 = 0X96;  
sfr P3M0 = 0Xb1;
sfr P3M1 = 0Xb2; 

/*
共阴极数码管0 - F的字形码 
“0” 3FH “8” 7FH  
“1” 06H “9” 6FH
“2” 5BH “A” 77H
“3” 4FH “b” 7CH
“4” 66H “C” 39H
“5” 6DH “d” 5EH
“6” 7DH “E” 79H
“7” 07H “F” 71H
*/
const unsigned char seg7[16] = { 0x3f, 0x06, 0x5b, 0x4f,
							0x66, 0x6d, 0x7d, 0x07,
							0x7f, 0x6f, 0x77, 0x7c,
							0x39, 0x5e, 0x79, 0x71 };    

sbit en1 = P2^6;
sbit en2 = P2^7;

//定义延时函数
void ms_delay(unsigned int t)
{
	unsigned  int  i;
	for (t; t > 0; t--)	//外层循环t次	 
		for (i = 110;i > 0; i--)	//内层循环110次		   
		;
}  

main()
{
	//配置端口模式为开漏输出 
	P0M1 = 0xff;
	P0M0 = 0xff; 
	P2M1 |= 0xc0;  //高2位置1	1100 0000
	P2M0 |= 0xc0;

	//把两个数码管都关闭 
	en2 = 1;
	en1 = 1;
	
	while(1)
	{
		P0 = seg7[9];	//送入9的段码 
		en2 = 0;	//显示DS2
		ms_delay(100);		   25hz 1000/25=20
		en2 = 1;	//关闭DS2	

		P0 = seg7[15];	//送入F的段码 
		en1 = 0;	//显示DS1
		ms_delay(100);
		en1 = 1;	//关闭DS1
	}
}