Programming 8x8 LED Matrix

This project is very simple for beginners, its vision is to show you how to send bytes to an 8x8 LED matrix. I have planned this in all letters

On the left side of the page, there will be an 8x8 matrix, with all the LEDs turned off, by clicking they will open, and code 5s representing what you are doing  with matrix, 

To make this project work you will need a library:

FrequencyTimer2

CODE
#define ROW_1 2
#define ROW_2 3
#define ROW_3 4
#define ROW_4 5
#define ROW_5 6
#define ROW_6 7
#define ROW_7 8
#define ROW_8 9

#define COL_1 10
#define COL_2 11
#define COL_3 12
#define COL_4 13
#define COL_5 A0
#define COL_6 A1
#define COL_7 A2
#define COL_8 A3

const byte rows[] = {
    ROW_1, ROW_2, ROW_3, ROW_4, ROW_5, ROW_6, ROW_7, ROW_8
};
const byte col[] = {
  COL_1,COL_2, COL_3, COL_4, COL_5, COL_6, COL_7, COL_8
};

// The display buffer
// It's prefilled with a smiling face (1 = ON, 0 = OFF)
byte ALL[] = {B11111111,B11111111,B11111111,B11111111,B11111111,B11111111,B11111111,B11111111};
byte EX[] = {B00000000,B00010000,B00010000,B00010000,B00010000,B00000000,B00010000,B00000000};
byte A[] = {  B00000000,B00111100,B01100110,B01100110,B01111110,B01100110,B01100110,B01100110};
byte B[] = {B01111000,B01001000,B01001000,B01110000,B01001000,B01000100,B01000100,B01111100};
byte C[] = {B00000000,B00011110,B00100000,B01000000,B01000000,B01000000,B00100000,B00011110};
byte D[] = {B00000000,B00111000,B00100100,B00100010,B00100010,B00100100,B00111000,B00000000};
byte E[] = {B00000000,B00111100,B00100000,B00111000,B00100000,B00100000,B00111100,B00000000};
byte F[] = {B00000000,B00111100,B00100000,B00111000,B00100000,B00100000,B00100000,B00000000};
byte G[] = {B00000000,B00111110,B00100000,B00100000,B00101110,B00100010,B00111110,B00000000};
byte H[] = {B00000000,B00100100,B00100100,B00111100,B00100100,B00100100,B00100100,B00000000};
byte I[] = {B00000000,B00111000,B00010000,B00010000,B00010000,B00010000,B00111000,B00000000};
byte J[] = {B00000000,B00011100,B00001000,B00001000,B00001000,B00101000,B00111000,B00000000};
byte K[] = {B00000000,B00100100,B00101000,B00110000,B00101000,B00100100,B00100100,B00000000};
byte L[] = {B00000000,B00100000,B00100000,B00100000,B00100000,B00100000,B00111100,B00000000};
byte M[] = {B00000000,B00000000,B01000100,B10101010,B10010010,B10000010,B10000010,B00000000};
byte N[] = {B00000000,B00100010,B00110010,B00101010,B00100110,B00100010,B00000000,B00000000};
byte O[] = {B00000000,B00111100,B01000010,B01000010,B01000010,B01000010,B00111100,B00000000};
byte P[] = {B00000000,B00111000,B00100100,B00100100,B00111000,B00100000,B00100000,B00000000};
byte Q[] = {B00000000,B00111100,B01000010,B01000010,B01000010,B01000110,B00111110,B00000001};
byte R[] = {B00000000,B00111000,B00100100,B00100100,B00111000,B00100100,B00100100,B00000000};
byte S[] = {B00000000,B00111100,B00100000,B00111100,B00000100,B00000100,B00111100,B00000000};
byte T[] = {B00000000,B01111100,B00010000,B00010000,B00010000,B00010000,B00010000,B00000000};
byte U[] = {B00000000,B01000010,B01000010,B01000010,B01000010,B00100100,B00011000,B00000000};
byte V[] = {B00000000,B00100010,B00100010,B00100010,B00010100,B00010100,B00001000,B00000000};
byte W[] = {B00000000,B10000010,B10010010,B01010100,B01010100,B00101000,B00000000,B00000000};
byte X[] = {B00000000,B01000010,B00100100,B00011000,B00011000,B00100100,B01000010,B00000000};
byte Y[] = {B00000000,B01000100,B00101000,B00010000,B00010000,B00010000,B00010000,B00000000};
byte Z[] = {B00000000,B00111100,B00000100,B00001000,B00010000,B00100000,B00111100,B00000000};

float timeCount = 0;

void setup() 
{
    // Open serial port
    Serial.begin(9600);
    
    // Set all used pins to OUTPUT
    // This is very important! If the pins are set to input
    // the display will be very dim.
    for (byte i = 2; i <= 13; i++)
        pinMode(i, OUTPUT);
    pinMode(A0, OUTPUT);
    pinMode(A1, OUTPUT);
    pinMode(A2, OUTPUT);
    pinMode(A3, OUTPUT);
}

void loop() {
  // This could be rewritten to not use a delay, which would make it appear brighter
delay(5);
timeCount += 1;

if(timeCount <  20) 
{
drawScreen(A);
} 
else if (timeCount <  40) 
{
drawScreen(R);
} 
else if (timeCount <  60) 
{
drawScreen(D);
} 
else if (timeCount <  80) 
{
drawScreen(U);
} 
else if (timeCount <  100) 
{
drawScreen(I);
} 
else if (timeCount <  120) 
{
drawScreen(N);
} 
else if (timeCount <  140) {
  drawScreen(O);
} 
else if (timeCount <  160) 
{
drawScreen(ALL);
} 
else if (timeCount <  180) 
{
drawScreen(ALL);
} 
else {
// back to the start
timeCount = 0;
}
}
 void  drawScreen(byte buffer2[])
 { 
   // Turn on each row in series
    for (byte i = 0; i < 8; i++)        // count next row
     {
        digitalWrite(rows[i], HIGH);    //initiate whole row
        for (byte a = 0; a < 8; a++)    // count next row
        {
          // if You set (~buffer2[i] >> a) then You will have positive
          digitalWrite(col[a], (buffer2[i] >> a) & 0x01); // initiate whole column
          
          delayMicroseconds(100);       // uncoment deley for diferent speed of display
          //delayMicroseconds(1000);
          //delay(10);
          //delay(100);
          
          digitalWrite(col[a], 1);      // reset whole column
        }
        digitalWrite(rows[i], LOW);     // reset whole row
        // otherwise last row will intersect with next row
    }
}
// 
  /* this is siplest resemplation how for loop is working with each row.
    digitalWrite(COL_1, (~b >> 0) & 0x01); // Get the 1st bit: 10000000
    digitalWrite(COL_2, (~b >> 1) & 0x01); // Get the 2nd bit: 01000000
    digitalWrite(COL_3, (~b >> 2) & 0x01); // Get the 3rd bit: 00100000
    digitalWrite(COL_4, (~b >> 3) & 0x01); // Get the 4th bit: 00010000
    digitalWrite(COL_5, (~b >> 4) & 0x01); // Get the 5th bit: 00001000
    digitalWrite(COL_6, (~b >> 5) & 0x01); // Get the 6th bit: 00000100
    digitalWrite(COL_7, (~b >> 6) & 0x01); // Get the 7th bit: 00000010
    digitalWrite(COL_8, (~b >> 7) & 0x01); // Get the 8th bit: 00000001
}*/
Connections diagram


Components used
1. Jumper wire
2. Breadboard
3. Arduino uno
4. 8*8 LED Matrix