LED流水灯

思路：每次LED灯熄灭后，下一个LED灯亮

#include <REGX52.H>
#include <INTRINS.H>


void Delay500ms()		//@12.000MHz
{
	unsigned char i, j, k;

	_nop_();
	i = 4;
	j = 205;
	k = 187;
	do
	{
		do
		{
			while (--k);
		} while (--j);
	} while (--i);
}


void main()
{
	while(1)
	{
			p2 = 0xFE;//1111 1110
			Delay500ms();
			p2 = 0xFD;//1111 1101 
			Delay500ms();
			p2 = 0xFB;//1111 1011 
			Delay500ms();
			p2 = 0xF7;//1111 0111 
			Delay500ms();
			p2 = 0xEF;//1110 1111 
			Delay500ms();
			p2 = 0xDF;//1101 1111
			Delay500ms();
			p2 = 0xBF;//1011 1111 
			Delay500ms();
			p2 = 0x7F;//0111 1111 
			Delay500ms();
		
	}
}

C51数据类型

可自定义延时时间【写一个带有参数的函数】

#include <REGX52.H>

void Delay1ms(unsigned int xms);		//@12.000MHz

void main()
{
	while(1)
	{
		P2=0xFE;//1111 1110
		Delay1ms(1000);
		P2=0xFD;//1111 1101
		Delay1ms(1000);
		P2=0xFB;//1111 1011
		Delay1ms(100);
		P2=0xF7;//1111 0111
		Delay1ms(100);
		P2=0xEF;//1110 1111
		Delay1ms(100);
		P2=0xDF;//1101 1111
		Delay1ms(100);
		P2=0xBF;//1011 1111
		Delay1ms(100);
		P2=0x7F;//0111 1111
		Delay1ms(100);
	}
}

void Delay1ms(unsigned int xms)		//@12.000MHz
{
	unsigned char i, j;
	while(xms)
	{
		i = 2;
		j = 239;
		do
		{
			while (--j);
		} while (--i);
		xms--;
	}
}