变量的定义:
宏定义:
#define uchar unsigned char
#define uint unsigned int
其意义类型替换:
把unsigned char 替换为uchar,把unsigned int 替换为uint
延时函数:
void delay(uint z)
{
uint x,y;
for(x = z;x > 0;x--)
for(y = 120;y > 0;y--);
}
120是通过调试得来的
以下程序均可:
#include<reg52.h>
sbit LED1 = P1^0;
unsigned int a;
void mian()
{
while(1)
{
P1 = P1 << 1;
a = 65535;
while(a--);
if(P1==0)
{
P1 = 0xff;
a = 65535;
while(a--);
}
}
}
#include<reg52.h>
unsigned int a = 65535;
unsigned char i;
void main()
{
for(i = 0;i<8;i++)
{
P1 = P1 <<1;
while(a--);
i++;
if(i==7)
{
i=0;
P1 = 0xff;
}
}
}
头文件intrins的函数使用:
_ crol_ 字符循环左移
_ cror_ 字符循环右移
_ nop_ 空操作8051 NOP 指令
#include<reg52.h>
#include<intins.h>
unsigned char i;
unsigned int a = 65535;
unsigned temp;
void main()
{
temp = 0xfe;
P1 = temp;
while(1)
{
for(i = 0;i<8;i++)
{
temp = _crol_(temp,1);
P1=temp;
while(a--);
}
}
}
#include<reg52.h>
#include<intrins.h>
#define uchar unsigned char
#define uint unsigned int
unsigned char i;
unsigned int a = 65535;
unsigned temp;
void delay(uint z)
{
uint x,y;
for(x = z;x > 0;x--)
for(y = 120;y > 0;y--);
}
void main()
{
temp = 0xfe;
P1 = temp;
while(1)
{
for(i = 0;i<8;i++)
{
temp = _crol_(temp,1);
P1=temp;
delay(500);
}
}
}