//sang dan, tat dan 2 portb, portd

#include "16f877a.h"

#include "def_877a.h"

#use delay(clock=4mhz)

char i,j,n;

//chuong trinh con tat dan

void tatdan()

{

portb=0x00;

portd=0x00;

delay_ms(50);

j=0b00000001;

for(i=1;i<=8;i++)

{

portd=j;

portb=j;

delay_ms(50);

j<<=1;

}

}

//chuong trinh con sang dan

void sangdan()

 {

portb=0xff;

portd=0xff;

delay_ms(50);

j=0b11111110;

for(i=1;i<=8;i++)

{

portb=j;

portd=j;

delay_ms(50);

j<<=1;

}

}

//chuong trinh chinh

void main()

{

trisb=0;

trisd=0;

while(true)

{

for(n=1;n<=3;n++)

sangdan();

for(n=1;n<=3;n++)

tatdan();

}

}