单片机原理及应用张刚毅数码管显示4乘4矩阵键盘键号按下时,显示对应的10进制

单片机原理及应用张刚毅数码管显示4乘4矩阵键盘键号按下时,显示对应的10进制

#include <reg52.h>
#include <intrins.h>
#define uchar unsigned char
#define uint unsigned int

uchar key;
unsigned char code disp_code[]={
0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
unsigned char code key_code[]={
0xee,0xed,0xeb,0xe7,0xde,0xdd,0xdb,0xd7,
0xbe,0xbd,0xbb,0xb7,0x7e,0x7d,0x7b,0x77 };

void delayms(uint ms)
{
uchar t;
while(ms--)
{
for(t = 0; t < 120; t++);
}
}


uchar keyscan()
{
uchar scan1,scan2,keycode,j;
P3=0xf0;
scan1=P3;
if((scan1&0xf0)!=0xf0) //判键是否按下
{
delayms(30); //延时30ms
scan1=P3;
if((scan1&0xf0)!=0xf0) //二次判键是否按下
{
P3=0x0f;
scan2=P3;
keycode=scan1|scan2; //组合成键编码
for(j=0;j<=15;j++)
{
if(keycode== key_code[j]) //查表得键值
{
key=j;
return(key);
}
}
}
}
else P3=0xff;
return (16);
}

void keydown()
{
P3=0x0f;
if((P3&0x0f)!=0x0f)
{
keyscan();
P0=disp_code[key];
beep();
}
}

main()
{
P0 = 0xbf;
P2 = 0x7f; //数码管显示"-"
P3 = 0xff;
while(1)
{
keydown();
}
}

你好！ 需要帮你写程序是吗 如有疑问，请追问。