int i; // counter variable 
int j; // pgm outputs codes 00000 to 00111 in portd 2-4 bits
int count=0;
int SW1=8;  //Set SW1 to Pin 8
int SwState= 0;

void setup(){
 DDRD = DDRD | B00011100;    // set direction bits for pins 2 to 4, leave 0 and 1 untouched
 //(xx | 00 = xx)  same as pinMode(pin, OUTPUT) for pins 2 to 4
 Serial.begin(9600); 
 pinMode(SW1,INPUT);
 digitalWrite(SW1, HIGH); //enable pullup. Switch connected to ground
} 

void loop(){ 
  while (digitalRead(SW1)==LOW) // check if switch is released
  {
    count++;
      if (count>7){  //restart after 7
     count=0;
    }
    // 3 bits manipulated 0 to 7
    PORTD = PORTD & B11100011;  // clear out bits 2 -4, leave pins 0 and 1 untouched (xx & 11 = xx)
    j = (count << 2);           // shift variable up to pins 2 - 7 - to avoid pins 0 and 1
    PORTD = PORTD | j;   // combine the port information with the new information for LED pins 
    Serial.print("count=");
    Serial.println(count);
    Serial.print("PORTD in BINary=");
    Serial.println(PORTD, BIN); // debug to show masking 
    
    delay(200); 
    
  }
  delay(200);
}