第1个回答 2013-09-08
#include<reg52.h>
#define uchar unsigned char
#define uint unsigned int
sbit beep=P2^3;
sbit dula=P2^6;
sbit wela=P2^7;
void delay(uint x)
{
uchar i,j; //延时X毫秒
for(i=0;i<x;i++)
for(j=0;j<110;j++);
}
uchar code table[]={
0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71};
void di(uchar x)
{
beep=0; //蜂鸣器发声音函数
delay(x);
beep=1;
}
void display(uchar z)
{
wela=1;
P0=0xfe;
wela=0;
P0=0xff;
dula=1;
P0=table[z];
dula=0;
}
void keyscan()
{uchar temp,key,i;
P3=0xfe;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delay(10);
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xee:
key=0;
break;
case 0xde:
key=1;
break;
case 0xbe:
key=2;
break;
case 0x7e:
key=3;
break;
}
while(temp!=0xf0)
{
temp=P3;
temp=temp&0xf0;
}
display(key);
for(i=0;i<4;i++)
{ if(key==i) di(30*i); }
}
}
P3=0xfd;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delay(10);
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xed:
key=4;
break;
case 0xdd:
key=5;
break;
case 0xbd:
key=6;
break;
case 0x7d:
key=7;
break;
}
while(temp!=0xf0)
{
temp=P3;
temp=temp&0xf0;
}
display(key);
for(i=4;i<8;i++)
{ if(key==i) di(30*i); }
}
}
P3=0xfb;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delay(10);
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xeb:
key=8;
break;
case 0xdb:
key=9;
break;
case 0xbb:
key=10;
break;
case 0x7b:
key=11;
break;
}
while(temp!=0xf0)
{
temp=P3;
temp=temp&0xf0;
}
display(key);
for(i=8;i<12;i++)
{ if(key==i) di(30*i); }
}
}
P3=0xf7;
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delay(10);
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xe7:
key=12;
break;
case 0xd7:
key=13;
break;
case 0xb7:
key=14;
break;
case 0x77:
key=15;
break;
}
while(temp!=0xf0)
{
temp=P3;
temp=temp&0xf0;
}
display(key);
for(i=12;i<16;i++)
{ if(key==i) di(30*i); }
}
}
}
void main()
{ P0=0;
while(1)
{
keyscan();
}
}
改变蜂鸣器的方波频率可以让他有不同的声音,就是改变di()函数里面的延时函数的数值