8x8 matrix tester

8x8Tester.ino

int row[8] = {7,  9,  6,  8,  2,  5,  3,  4};
int col[8] = {15, 10, 11, 13, 12, 14, 16, 17};

// the setup routine runs once when you press reset:
void setup() {
  // open a serial port
  Serial.begin(9600);
  
  // initialize the row and column pins as outputs, set rows low, set columns high
  for (int i = 0; i < 8; i++) {
    pinMode (row[i], OUTPUT);
    digitalWrite(row[i], LOW);
    pinMode (col[i], OUTPUT);
    digitalWrite(col[i], HIGH);    
  }
  
  // test all leds
  for (int r=0; r<8; r++) {
    if (r > 0) {
      digitalWrite(row[r-1], LOW);
    }
    else {
      digitalWrite(row[7], LOW);
    }
    digitalWrite(row[r], HIGH);
    for (int c = 0; c<8; c++) {
      if (c > 0) {
        digitalWrite(col[c-1], HIGH);
      }
      else {
        digitalWrite(col[7], HIGH);
      }
      digitalWrite(col[c], LOW);
      delay(20);
    }  
  }
}

// the loop routine runs over and over again forever:
void loop() {
}