#include <8052.h>
//CPU freq in kHz
#define F_CPU 3072


/* sleep_10ms is not very spot on, but good enough */
#define sleep_ms(__x) for(int __i = 0; __i < (__x * F_CPU - 60)/120; __i++);
#define sleep_10ms(x) for(int __j = 0; __j < (x * F_CPU - 60)/360; __j++)\
    sleep_ms(x/10);

int main(void){
  while(1){
    
    P1 = 0xFF;
    sleep_10ms(10);
    P1 = 0x00;
    sleep_10ms(10);
  }
}