#include <reg51.h>
typedef unsigned char uint8;
typedef unsigned char uint16;
void main()
{
uint16 i;
while(1)
{
P0 =0xFE;
for(i=0;i<20000;i++);
P0 =0xFD;
for(i=0;i<20000;i++);
P0 =0xFB;
for(i=0;i<20000;i++);
P0 =0xF7;
for(i=0;i<20000;i++);
P0 =0xEF;
for(i=0;i<20000;i++);
P0 =0xDF;
for(i=0;i<20000;i++);
P0 =0xBF;
for(i=0;i<20000;i++);
P0 =0x7F;
for(i=0;i<20000;i++);
}
}
typedef unsigned char uint8;
typedef unsigned char uint16;
void main()
{
uint16 i;
while(1)
{
P0 =0xFE;
for(i=0;i<20000;i++);
P0 =0xFD;
for(i=0;i<20000;i++);
P0 =0xFB;
for(i=0;i<20000;i++);
P0 =0xF7;
for(i=0;i<20000;i++);
P0 =0xEF;
for(i=0;i<20000;i++);
P0 =0xDF;
for(i=0;i<20000;i++);
P0 =0xBF;
for(i=0;i<20000;i++);
P0 =0x7F;
for(i=0;i<20000;i++);
}
}