da转换.c

51单片机入门级资料。流水灯

#include<reg52.h>
#define uchar unsigned char
sbit rd=P3^2;
sbit wr=P3^6;
sbit duan=P2^6;
sbit wei=P2^7;
uchar dig;
void delay(uchar);
main()
{
	wei=0;
	duan=0;
	rd=0;
	wr=0;
	while(1)
	{
		P0=dig;
        delay(30);
		dig++;
		if(dig==255)
		{
			for(;dig>1;dig--)
			{
				P0=dig;
				delay(30);
			}
		}
		
				
	}
}

void delay(uchar x)
{
	uchar a;
	unsigned int b;
	for(a=x;a>0;a--)
		for(b=100;b>0;b--);
}