void setup() {
  // put your setup code here, to run once:
  volatile char *dr1,*dr2,*dr3,*dr4;
  dr1=0x30;
  dr2=0x107;
  dr3=0x21;
  dr4=0x27;
  *dr1=0xFF;
  *dr2=0xff;
  *dr3=0xff;
*dr4=0xff;
}

void loop() {
  // put your main code here, to run repeatedly:
  volatile char *out,*out1,*out2,*out3;
  volatile long  i;
  out=0x31;
  out2=0x22;
  out1=0x108;
  out3=0x28;
  *out=0x6d;
  *out1=0b00111110;
  *out2=0x3f;
  *out3=0b0000111;
for(i =0;i<100000;i++);
*out=0x00;
*out1=0x00;
*out2=0x00;
*out3=0x00;
for(i =0;i<100000;i++);
}