#include <LedControl.h>

LedControl lc = LedControl(10, 8, 9, 1);

// Binary representation of letters M, A, R, Y, G, O, L, and D
const uint8_t LETTER_IMAGES[][8] = {
  // M
  {0b10000001, 0b11000011, 0b10100101, 0b10011001, 0b10000001, 0b10000001, 0b10000001, 0b10000001},
  // A
  {0b00111100, 0b01000010, 0b01000010, 0b01111110, 0b01000010, 0b01000010, 0b01000010, 0b00000000},
  // R
  {0b01111100, 0b01000010, 0b01000010, 0b01111100, 0b01001000, 0b01000100, 0b01000010, 0b00000000},
  // Y
  {0b01000010, 0b01000010, 0b01000010, 0b00111100, 0b00001000, 0b00001000, 0b00001000, 0b00000000},
  // G
  {0b00111100, 0b01000010, 0b01000000, 0b01001110, 0b01000010, 0b01000010, 0b00111100, 0b00000000},
  // O
  {0b00111100, 0b01000010, 0b01000010, 0b01000010, 0b01000010, 0b01000010, 0b00111100, 0b00000000},
  // L
  {0b01000000, 0b01000000, 0b01000000, 0b01000000, 0b01000000, 0b01000000, 0b01111110, 0b00000000},
  // D
  {0b01111100, 0b01000010, 0b01000010, 0b01000010, 0b01000010, 0b01000010, 0b01111100, 0b00000000}
};
const int LETTER_IMAGES_LEN = sizeof(LETTER_IMAGES) / 8;

void displayLetter(const uint8_t letter[]) {
  for (int i = 0; i < 8; i++) {
    lc.setRow(0, i, letter[i]);
  }
}

void setup() {
  lc.shutdown(0, false);
  lc.setIntensity(0, 15);
  lc.clearDisplay(0);
}

void loop() {
  // Display letters M, A, R, Y, G, O, L, and D
  for (int letterIndex = 0; letterIndex < LETTER_IMAGES_LEN; letterIndex++) {
    displayLetter(LETTER_IMAGES[letterIndex]);
    delay(1000);
  }
}