/************************************************高手出来指点下下面16个按键分别按下会显示什么数字。
跳线设置:J7拔掉,双排针除PSEN外全部插上
硬件结构框架:
1,八位八段数码管
2,MCU STC89C52
3,4*4距阵键盘
显示效果:
1,按下4*4键盘数码管显示显示0-9
2,带松手检测
相关知识点:
1,键盘的动态扫描
************************************************/
#include"AT89x52.h"
#include"math.h"
#define uint unsigned int
#define uchar unsigned char
sbit DUAN=P2^6; //74HC573的LE端 U5 LED的段选端
sbit WEI=P2^7; //74HC573的LE端 U4 LED的位选端
uchar Temp[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f}; //共阴显示字库
uchar keyboard_Scan[]={0xef,0xdf,0xbf,0x7f};
uchar in;
void delay(uint z) //1ms延时
{
uint x,y;
for(x=z;x>0;x--)
for(y=110;y>0;y--);
}
void duan_1(uchar duan)
{
DUAN=1;
P0=Temp[duan];
DUAN=0;
delay(10);
}
uchar Keyboard()
{
uchar i,j,pc;
for(i=0;i<4;i++)
{
P3=keyboard_Scan;
pc=P3;
pc=pc<<4|0x0f; //假如说有按键按下
for(j=0;j<4;j++) //将扫描值与扫描按键值比较
{
if(keyboard_Scan[j]==pc)in=i*4+j;
if(in>=10)in=15-in;
while(keyboard_Scan!=P3) //松手检测
{
P3=keyboard_Scan;
}
}
}
return in;
}
main()
{
WEI=1;
P0=0;
WEI=0;
while(1)
{
duan_1(Keyboard());
}
}
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