#include<reg51.h>
#include<stdio.h>
#inclde<intrins. h>
void delay(unsigned char time)//必须声明函数，否则会出现下面的错误：
void main()
{
P0 = 0xfe;//P必须大写
while(1)
{
delay(200);
P0 = _cror_(P0,1);
}
}
void delay()
{
unsigned char I,j;
for(i=0;i<=time;i++)
{
for(j=0;j<=200;j++)
{ _nop_();//空指令，根据单片机的机器周期计算
}
}
}
另一实现的方法：
sbit 位的应用
数据类型笔记：
|
数据类型
|
位数
|
字节数
|
数值范围
|
说明
|
|
bit
|
1
|
|
0 or 1
|
位型
|
|
Signed char
|
8
|
1
|
-128——+127
|
有符号字节型
|
|
Unsigned char
|
8
|
1
|
0~255
|
字符或者八位无符号整数
|
|
enum
|
16
|
2
|
-32768~+32767
|
枚举型
|
|
Signed short
|
16
|
2
|
-32768~+32767
|
有符号短整型
|
|
Unsigned short
|
16
|
2
|
0~6535
|
无符号短整型
|
|
Signed int
|
16
|
2
|
-32768~32767
|
|
|
Unsigned int
|
|
|
|
|
|
Signed long
|
|
|
|
|
|
Unsigned long
|
|
|
|
|
|
float
|
|
|
|
|
|
Sbit
|
1
|
|
0 1
|
位型
|
|
Sfr
|
8
|
1
|
0~255
|
8位特殊功能寄存器
|
|
Sfr16
|
|
|
|
|
|
|
|
|
|
|
程序代码：
#include<reg51.h> #include<stdio.h> #include<intrins.h> sbit P0_0 = P0^0;//I/O口的定义方法，两者的区别，不这样定义的话就会说没有定义 sbit P0_1 = P0^1; sbit P0_2 = P0^2; sbit P0_3 = P0^3; sbit P0_4 = P0^4; sbit P0_5 = p0^5; sbit P0_6 = P0^6; sbit P0_7 = P0^7; void delay(unsigned char time);//函数声明，重要 void main() { while(1) { P0_0 = 0; delay(200); P0_1 = 0; delay(200); P0_3 = 0; delay(200); P0_4 = 0; delay(200); P0_5 = 0; delay(200); P0_6 = 0; delay(200); P0_7 = 0; delay(200); } void delay(unsigned char time) { unsigned char i,j; for(i=0;i<=time;i++) { for(j=0;j<=200;j++) { _nop_() } } } 控制亮灭程序： #include<reg51.h>//端口定义已包含在此头文件中，故P0可以直接赋值 #include<stdio.h> #include<intrins.h> void delay(unsigned char time); void delay(unsigned char time) { unsigned i,j; for(i=0;i<=time;i++) { for(j=0;j<=200;j++) { _nop_(); } } } void main() { while(1) { P0 = 0x00; delay(200); P0 = 0xff; delay(200); } }