单片机语法问题详见scan函数

只看该作者 · 2014-11-4 21:01

//目的：显示一个固定的数字

//有几个问题没搞明白，详见scan程序注释

# include <reg52.h>



typedef unsigned char uchar;

typedef unsigned int uint;

sbit addr0 = P1^0;

sbit addr1 = P1^1;

sbit addr2 = P1^2;

sbit addr3 = P1^3;

sbit enled = P1^4;

uchar a, b, c = 0;

uchar number[16] = { 0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,

0x80,0x90,0x88,0x83,0xa7,0xa1,0x86,0x8e

};





void scan (void);



void main (void)

{



addr3 = 1;

while (1)

{

scan();

} 

}





void scan (void)

{ 

//uchar a,b,c; 为什么不能定义为局部变量

uchar i = 158;//要显示的数字

enled = 1;// 这句和上边那句（uchar i = 158）位置为什么不能调啊

a = i/100;

addr0 = 1;

addr1 = 0;

addr2 = 1;

P0 = number[a]; //显示第一位

enled = 0;



enled = 1; 

b = i%100/10;

addr0 = 0;

addr1 = 0;

addr2 = 1;

P0 = number[b]; //显示第二位

enled = 0;



enled = 1;

c = i%100%10;

addr0 = 1;

addr1 = 1;

addr2 = 0;

P0 = number[c]; //显示第三位

enled = 0; 

}