#include "megan.h";
void setup() {
  // put your setup code here, to run once:
    set_port_dir();

}

void loop() {
  // put your main code here, to run repeatedly:
  volatile char x;
  volatile long i;
   
      x=128+16+8+1;
  GLOW_LSB_LED_only(x);
  wait_some_time_here();
  x=0;
  GLOW_LSB_LED_only(x);
  wait_some_time_here();
     
     
   

  

}


sketch.ino

diagram.json

void set_port_dir(void);
void GLOW_LSB_LED_only(char);
void wait_some_time_here(void);
void set_port_dir(void)
{
  volatile char *dirf=(char *)0x30;
                 dirf=0xFF;
}
void GLOW_LSB_LED_only(char out)
{
  volatile char *outf=(char *)0x31;
                *outf=out;
}
void wait_some_time_here(void)
{
  volatile long i;
  for(i=0;i<500000;i++);
}