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SAnwandter1
Published

Programming 8x8 LED Matrix

Sending Bytes to an 8x8 LED Matrix.

BeginnerProtip472,294
Programming 8x8 LED Matrix

Things used in this project

Hardware components

Jumper wires (generic)
Jumper wires (generic)
×16
Breadboard (generic)
Breadboard (generic)
×2
Arduino UNO
Arduino UNO
×1
Adafruit 8x8 LED Matrix
×1
Adafruit USB Cable - Standard A-B for ARDUINO
×1

Software apps and online services

Arduino IDE
Arduino IDE

Story

Read more

Schematics

Connections diagram

This is to make the connections easier

Code

Here's the code

Arduino
//update from SAnwandter

#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
}*/

Credits

SAnwandter1
3 projects • 153 followers

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