haoma.c

本文件包含了使用C语言编写单片机的各种入门程序

#include<reg51.h>
sbit sda=P0^2;
sbit scl=P0^3;
unsigned int key1,b=0;
code int led[27]={0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0x11,
0xd3,0xd3,0x92,0xfe,0x32,0xd7,0xd4,
0x32,0x32,0x18,0x32,0xff,0xff,0xff,
0xff,0xff,0xff,0xff};

void delay(int t)
{
int k;
for(;t>0;t--)
for(k=0;k<300;k++);
}

shift(int k)
{
int n,led1=led[k];
for(n=0;n<8;n++)
{
scl=0;
if(led1&0x80)sda=1;
else sda=0;
scl=1;
scl=0;
sda==0;
led1=led1<<1;
}
}

keyscan()
{
int k1,k2;
P2=0x0f;
k1=P2;
P2=0xf0;
k2=P2;
key1=k1+k2;
switch(key1)
{
 case 0xe7: b=b<19?b+1:0;break;
 default:break;
}

}

main()
{
while(1)
{
keyscan();
shift(b);
shift(b+1);
shift(b+2);
shift(b+3);
shift(b+4);
shift(b+5);
shift(b+6);
shift(b+7);
delay(500);
}
}