跑马灯来回跑

流水灯来回跑

#include<reg52.h>


void delay(unsigned int t);




void main()
{
    unsigned char i;
    delay(20000);
while (1)
{
for(i=0;i<8;i++)
{
  P2 = ~(0x01<<i);
  delay(20000);
}
for(i=0;i<7;i++)
{
  P2 = ~(0x80>>i);
  delay(20000);
}
}

}
void delay(unsigned int t)
{
while(t --);
}