// Pin definitions
const int DS = 8;  // Data (SER)
const int SH = 7;  // Clock (SRCLK)
const int ST = 4;  // Latch (RCLK)

#define stCLK(x) digitalWrite(ST, x)
#define shCLK(x) digitalWrite(SH, x)
#define dataS(x) digitalWrite(DS, x)

void setup() 
{ pinMode(DS, OUTPUT);
  pinMode(SH, OUTPUT);
  pinMode(ST, OUTPUT);

  digitalWrite(DS, LOW);
  digitalWrite(SH, LOW);
  digitalWrite(ST, LOW);
}

uint8_t ledSeq[] = {0x81,0x42,0x24,0x18,0x24,0x42,0x81,0x00};

void loop() 
{ for(uint8_t i=0;i<sizeof(ledSeq);i++)
	{
		leds(ledSeq[i]);
		delay(200);
	}
}

void leds(uint8_t x)
{ stCLK(LOW);  
  for(int8_t i = 7; i >= 0; i--)
  { shCLK(LOW);
    if(x & (1 << i))	dataS(HIGH);
    else					    dataS(LOW);
    shCLK(HIGH);
  }
  stCLK(HIGH);  
}