#define  LATCH  13
#define  CLOCK  12
#define  DATA   11
#define  ACCELX 0
#define  ACCELY 1
byte matrix[8];
int idx = 0;
int nn;

void setup() {
  pinMode(CLOCK, OUTPUT);
  pinMode(LATCH, OUTPUT);
  pinMode(DATA,  OUTPUT);
  digitalWrite(CLOCK, LOW);
  digitalWrite(LATCH, LOW);
  digitalWrite(DATA,  LOW);
  initLED();
  clearLED();
  clearMatrix();
  nn=3;
  matrix[nn]=0x08;
}

#define DELAY 40
#define LIMIT 0x20
#define ULIMIT 0x200+LIMIT
#define LLIMIT 0x200-LIMIT
int pp;
byte tn,temp;
void loop() {
  pp=analogRead(ACCELX);
  if (pp>ULIMIT) {
    temp=matrix[nn];
    matrix[nn]=0;
    if(++nn==8) nn=7;;
    matrix[nn]=temp;
  }
  if (pp<LLIMIT) {
    temp=matrix[nn];
    matrix[nn]=0;
    if(--nn<0) nn=0;;
    matrix[nn]=temp;
    }

  pp=analogRead(ACCELY);
  if (pp>ULIMIT) {
    temp=matrix[nn];
    matrix[nn]<<=1;
    if(matrix[nn]==0) matrix[nn]=temp;
  }
  if (pp<LLIMIT) {
    temp=matrix[nn];
    matrix[nn]>>=1;
    if(matrix[nn]==0) matrix[nn]=temp;
    }

  refreshLED();
  delay(DELAY);
}

/* 
* The source code below is quotation from 
*   http://www.bryanchung.net/?p=177
*/

void ledOut(int n) {
  digitalWrite(LATCH, LOW);
  shiftOut(DATA, CLOCK, MSBFIRST, (n>>8)); 
  shiftOut(DATA, CLOCK, MSBFIRST, n);
  digitalWrite(LATCH, HIGH);
  delay(1);
  digitalWrite(LATCH, LOW);
}

void initLED() {
  ledOut(0x0B07);
  ledOut(0x0A07);
  ledOut(0x0900);
  ledOut(0x0C01);
}

void clearLED() {
  int n;
  for(n=1;n<9;n++){
    ledOut((n<<8)+0x00);
  }
}

void clearMatrix(){
  for(int n=0;n<8;matrix[n++]=0);
}

void refreshLED() {
  int n1, n2, n3;
  for (int i=0;i<8;i++) {
    n1 = i+1;
    n2 = matrix[i];
    n3 = (n1<<8)+n2;
    ledOut(n3);
  }
}

void updateLED(int i, int j, boolean b) {
  int t = 1;
  int n = 0;
  int m = 0;
  if (j==0) {
    m = 7;
  }
  else {
    m = j-1;
  }
  n = t<<m;
  if (b) {
    matrix[i] = n | matrix[i];
  }
  else {
    n = ~n;
    matrix[i] = n & matrix[i];
  }
}