zuoyyi.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 b,n;
code unsigned 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;
}
}

void main()
{
for(n=0;n<20;n++)
{
b=n+7;
shift(b);
P2=0xaa;
b=n+6;
shift(b);
P2=0x55;
b=n+5;
shift(b);
P2=0xaa;
b=n+4;
shift(b);
P2=0x55;
b=n+3;
shift(b);
P2=0xaa;
b=n+2;
shift(b);
P2=0x55;
b=n+1;
shift(b);
P2=0xaa;
b=n;
shift(b);
P2=0x55;
delay(400);
}
for(n=0;n<20;n++)
{
shift(n);
P2=0x55;
shift(n+1);
P2=0xaa;
shift(n+2);
P2=0x55;
shift(n+3);
P2=0xaa;
shift(n+4);
P2=0x55;
shift(n+5);
P2=0xaa;
shift(n+6);
P2=0x55;
shift(n+7);
P2=0xaa;
delay(400);
}
}