x2.c

来自「51单片机控制简易数控直流电源源码加仿真。」· C语言 代码 · 共 48 行

#include <AT89X51.H>
#include "lcd_h.h"
const seven_seg[10]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};
const scan[4]={0xF7,0xFB,0xFD,0xFE};
void delay2(void)
{
     unsigned int n;
     for (n=0;n<300;n++);
}
void delay1(void)
{
     unsigned int n;
     for (n=0;n<30000;n++);
}
void key(void)
{    
     int i=0,n=0,key;
     P1=0xF0;
     do
     {
        if (P1!=0xF0) delay2();
        if (P1!=0xF0) 
           {
             for (i=0;i<=3;i++)
             {
                 P1=scan[i];
				 switch(P1)
				 {
				        case 0xD7: key=0;break;
						case 0xEB: key=1;break;
						case 0xDB: key=2;break;
						case 0xBB: key=3;break;
						case 0xED: key=4;break;
						case 0xDD: key=5;break;
						case 0xBD: key=6;break;
						case 0xEE: key=7;break;
						case 0xDE: key=8;break;
						case 0xBE: key=9;break;
				 }
             }
		     P2=seven_seg[key];
			 delay1();
             P1=0xF0;
			 break;
           }
     }while(1);        
}