// based on an orginal sketch by Arduino forum member "danigom"
// http://forum.arduino.cc/index.php?action=profile;u=188950

#include <avr/pgmspace.h>
#include <LedControl.h>

const int numDevices = 4;      // number of MAX7219s used
const long scrollDelay = 50;   // adjust scrolling speed

unsigned long bufferLong [16] = {0};

LedControl lc = LedControl(5,7,6,numDevices);

const unsigned char scrollText[] PROGMEM ={
    "a!Byfyrdse!/\0"};

void setup(){
    for (int x=0; x<numDevices; x++){
        lc.shutdown(x,false);       //The MAX72XX is in power-saving mode on startup
        lc.setIntensity(x,1);       // Set the brightness to default value
        lc.clearDisplay(x);         // and clear the display
    }
}

void loop(){
    scrollMessage(scrollText);
    // scrollFont();
}

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////

int trim_matrix(const unsigned char* font) {
    int i;
    int j;
    const unsigned char product = 1;
    int ret = 0;
    unsigned char temp;
    for (i = 0; i < 8; i++) {
        temp = font[i];
        for (j = 0; j < 8; j++) {
        if ((product & temp) == 1) {
            if (ret < (8 - j)) { // 8-j == length
               ret = 8 - j;
            }
            break;
        }
        temp = temp >> 1;
        }
    }

    return ret;
}

const unsigned char font5x7[] PROGMEM = {      //Numeric Font Matrix (Arranged as 7x font data + 1x kerning data)
    B00000000,  //Space (Char 0x20)
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,

    B10000000,  //!
    B10000000,
    B10000000,
    B10000000,
    B00000000,
    B00000000,
    B10000000,
    B00000000,

    B10100000,  //"
    B10100000,
    B10100000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,

    B01010000,  //#
    B01010000,
    B11111000,
    B01010000,
    B11111000,
    B01010000,
    B01010000,
    B00000000,

    B00100000,  //$
    B01111000,
    B10100000,
    B01110000,
    B00101000,
    B11110000,
    B00100000,
    B00000000,

    B11000000,  //%
    B11001000,
    B00010000,
    B00100000,
    B01000000,
    B10011000,
    B00011000,
    B00000000,

    B01100000,  //&
    B10010000,
    B10100000,
    B01000000,
    B10101000,
    B10010000,
    B01101000,
    B00000000,

    B11000000,  //'
    B01000000,
    B10000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,

    B00100000,  //(
    B01000000,
    B10000000,
    B10000000,
    B10000000,
    B01000000,
    B00100000,
    B00000000,

    B10000000,  //)
    B01000000,
    B00100000,
    B00100000,
    B00100000,
    B01000000,
    B10000000,
    B00000000,

    B00000000,  //*
    B00100000,
    B10101000,
    B01110000,
    B10101000,
    B00100000,
    B00000000,
    B00000000,

    B00000000,  //+
    B00100000,
    B00100000,
    B11111000,
    B00100000,
    B00100000,
    B00000000,
    B00000000,

    B00000000,  //,
    B00000000,
    B00000000,
    B00000000,
    B11000000,
    B01000000,
    B10000000,
    B00000000,

    B00000000,  //-
    B00000000,
    B11111000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,

    B00000000,  //.
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B11000000,
    B11000000,
    B00000000,

    B00000000,  ///
    B00001000,
    B00010000,
    B00100000,
    B01000000,
    B10000000,
    B00000000,
    B00000000,

    B01110000,  //0
    B10001000,
    B10011000,
    B10101000,
    B11001000,
    B10001000,
    B01110000,
    B00000000,

    B01000000,  //1
    B11000000,
    B01000000,
    B01000000,
    B01000000,
    B01000000,
    B11100000,
    B00000000,

    B01110000,  //2
    B10001000,
    B00001000,
    B00010000,
    B00100000,
    B01000000,
    B11111000,
    B00000000,

    B11111000,  //3
    B00010000,
    B00100000,
    B00010000,
    B00001000,
    B10001000,
    B01110000,
    B00000000,

    B00010000,  //4
    B00110000,
    B01010000,
    B10010000,
    B11111000,
    B00010000,
    B00010000,
    B00000000,

    B11111000,  //5
    B10000000,
    B11110000,
    B00001000,
    B00001000,
    B10001000,
    B01110000,
    B00000000,

    B00110000,  //6
    B01000000,
    B10000000,
    B11110000,
    B10001000,
    B10001000,
    B01110000,
    B00000000,

    B11111000,  //7
    B10001000,
    B00001000,
    B00010000,
    B00100000,
    B00100000,
    B00100000,
    B00000000,

    B01110000,  //8
    B10001000,
    B10001000,
    B01110000,
    B10001000,
    B10001000,
    B01110000,
    B00000000,

    B01110000,  //9
    B10001000,
    B10001000,
    B01111000,
    B00001000,
    B00010000,
    B01100000,
    B00000000,

    B00000000,  //:
    B11000000,
    B11000000,
    B00000000,
    B11000000,
    B11000000,
    B00000000,
    B00000000,

    B00000000,  //;
    B11000000,
    B11000000,
    B00000000,
    B11000000,
    B01000000,
    B10000000,
    B00000000,

    B00010000,  //<
    B00100000,
    B01000000,
    B10000000,
    B01000000,
    B00100000,
    B00010000,
    B00000000,

    B00000000,  //=
    B00000000,
    B11111000,
    B00000000,
    B11111000,
    B00000000,
    B00000000,
    B00000000,

    B10000000,  //>
    B01000000,
    B00100000,
    B00010000,
    B00100000,
    B01000000,
    B10000000,
    B00000000,

    B01110000,  //?
    B10001000,
    B00001000,
    B00010000,
    B00100000,
    B00000000,
    B00100000,
    B00000000,

    B01110000,  //@
    B10001000,
    B00001000,
    B01101000,
    B10101000,
    B10101000,
    B01110000,
    B00000000,

    B01110000,  //A
    B10001000,
    B10001000,
    B10001000,
    B11111000,
    B10001000,
    B10001000,
    B00000000,

    B11110000,  //B
    B10001000,
    B10001000,
    B11110000,
    B10001000,
    B10001000,
    B11110000,
    B00000000,

    B01110000,  //C
    B10001000,
    B10000000,
    B10000000,
    B10000000,
    B10001000,
    B01110000,
    B00000000,

    B11100000,  //D
    B10010000,
    B10001000,
    B10001000,
    B10001000,
    B10010000,
    B11100000,
    B00000000,

    B11111000,  //E
    B10000000,
    B10000000,
    B11110000,
    B10000000,
    B10000000,
    B11111000,
    B00000000,

    B11111000,  //F
    B10000000,
    B10000000,
    B11110000,
    B10000000,
    B10000000,
    B10000000,
    B00000000,

    B01110000,  //G
    B10001000,
    B10000000,
    B10111000,
    B10001000,
    B10001000,
    B01111000,
    B00000000,

    B10001000,  //H
    B10001000,
    B10001000,
    B11111000,
    B10001000,
    B10001000,
    B10001000,
    B00000000,

    B11100000,  //I
    B01000000,
    B01000000,
    B01000000,
    B01000000,
    B01000000,
    B11100000,
    B00000000,

    B00111000,  //J
    B00010000,
    B00010000,
    B00010000,
    B00010000,
    B10010000,
    B01100000,
    B00000000,

    B10001000,  //K
    B10010000,
    B10100000,
    B11000000,
    B10100000,
    B10010000,
    B10001000,
    B00000000,

    B10000000,  //L
    B10000000,
    B10000000,
    B10000000,
    B10000000,
    B10000000,
    B11111000,
    B00000000,

    B10001000,  //M
    B11011000,
    B10101000,
    B10101000,
    B10001000,
    B10001000,
    B10001000,
    B00000000,

    B10001000,  //N
    B10001000,
    B11001000,
    B10101000,
    B10011000,
    B10001000,
    B10001000,
    B00000000,

    B01110000,  //O
    B10001000,
    B10001000,
    B10001000,
    B10001000,
    B10001000,
    B01110000,
    B00000000,

    B11110000,  //P
    B10001000,
    B10001000,
    B11110000,
    B10000000,
    B10000000,
    B10000000,
    B00000000,

    B01110000,  //Q
    B10001000,
    B10001000,
    B10001000,
    B10101000,
    B10010000,
    B01101000,
    B00000000,

    B11110000,  //R
    B10001000,
    B10001000,
    B11110000,
    B10100000,
    B10010000,
    B10001000,
    B00000000,

    B01111000,  //S
    B10000000,
    B10000000,
    B01110000,
    B00001000,
    B00001000,
    B11110000,
    B00000000,

    B11111000,  //T
    B00100000,
    B00100000,
    B00100000,
    B00100000,
    B00100000,
    B00100000,
    B00000000,

    B10001000,  //U
    B10001000,
    B10001000,
    B10001000,
    B10001000,
    B10001000,
    B01110000,
    B00000000,

    B10001000,  //V
    B10001000,
    B10001000,
    B10001000,
    B10001000,
    B01010000,
    B00100000,
    B00000000,

    B10001000,  //W
    B10001000,
    B10001000,
    B10101000,
    B10101000,
    B10101000,
    B01010000,
    B00000000,

    B10001000,  //X
    B10001000,
    B01010000,
    B00100000,
    B01010000,
    B10001000,
    B10001000,
    B00000000,

    B10001000,  //Y
    B10001000,
    B10001000,
    B01010000,
    B00100000,
    B00100000,
    B00100000,
    B00000000,

    B11111000,  //Z
    B00001000,
    B00010000,
    B00100000,
    B01000000,
    B10000000,
    B11111000,
    B00000000,

    B11100000,  //[
    B10000000,
    B10000000,
    B10000000,
    B10000000,
    B10000000,
    B11100000,
    B00000000,

    B00000000,  //(Backward Slash)
    B10000000,
    B01000000,
    B00100000,
    B00010000,
    B00001000,
    B00000000,
    B00000000,

    B11100000,  //]
    B00100000,
    B00100000,
    B00100000,
    B00100000,
    B00100000,
    B11100000,
    B00000000,

    B00100000,  //^
    B01010000,
    B10001000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,

    B00000000,  //_
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B11111000,
    B00000000,

    B10000000,  //`
    B01000000,
    B00100000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,
    B00000000,

    B00000000,  //a
    B00000000,
    B01110000,
    B00001000,
    B01111000,
    B10001000,
    B01111000,
    B00000000,

    B10000000,  //b
    B10000000,
    B10110000,
    B11001000,
    B10001000,
    B10001000,
    B11110000,
    B00000000,

    B00000000,  //c
    B00000000,
    B01110000,
    B10001000,
    B10000000,
    B10001000,
    B01110000,
    B00000000,

    B00001000,  //d
    B00001000,
    B01101000,
    B10011000,
    B10001000,
    B10001000,
    B01111000,
    B00000000,

    B00000000,  //e
    B00000000,
    B01110000,
    B10001000,
    B11111000,
    B10000000,
    B01110000,
    B00000000,

    B00110000,  //f
    B01001000,
    B01000000,
    B11100000,
    B01000000,
    B01000000,
    B01000000,
    B00000000,

    B00000000,  //g
    B01111000,
    B10001000,
    B10001000,
    B01111000,
    B00001000,
    B01110000,
    B00000000,

    B10000000,  //h
    B10000000,
    B10110000,
    B11001000,
    B10001000,
    B10001000,
    B10001000,
    B00000000,

    B01000000,  //i
    B00000000,
    B11000000,
    B01000000,
    B01000000,
    B01000000,
    B11100000,
    B00000000,

    B00010000,  //j
    B00000000,
    B00110000,
    B00010000,
    B00010000,
    B10010000,
    B01100000,
    B00000000,

    B10000000,  //k
    B10000000,
    B10010000,
    B10100000,
    B11000000,
    B10100000,
    B10010000,
    B00000000,

    B11000000,  //l
    B01000000,
    B01000000,
    B01000000,
    B01000000,
    B01000000,
    B11100000,
    B00000000,

    B00000000,  //m
    B00000000,
    B11010000,
    B10101000,
    B10101000,
    B10001000,
    B10001000,
    B00000000,

    B00000000,  //n
    B00000000,
    B10110000,
    B11001000,
    B10001000,
    B10001000,
    B10001000,
    B00000000,

    B00000000,  //o
    B00000000,
    B01110000,
    B10001000,
    B10001000,
    B10001000,
    B01110000,
    B00000000,

    B00000000,  //p
    B00000000,
    B11110000,
    B10001000,
    B11110000,
    B10000000,
    B10000000,
    B00000000,

    B00000000,  //q
    B00000000,
    B01101000,
    B10011000,
    B01111000,
    B00001000,
    B00001000,
    B00000000,

    B00000000,  //r
    B00000000,
    B10110000,
    B11001000,
    B10000000,
    B10000000,
    B10000000,
    B00000000,

    B00000000,  //s
    B00000000,
    B01110000,
    B10000000,
    B01110000,
    B00001000,
    B11110000,
    B00000000,

    B01000000,  //t
    B01000000,
    B11100000,
    B01000000,
    B01000000,
    B01001000,
    B00110000,
    B00000000,

    B00000000,  //u
    B00000000,
    B10001000,
    B10001000,
    B10001000,
    B10011000,
    B01101000,
    B00000000,

    B00000000,  //v
    B00000000,
    B10001000,
    B10001000,
    B10001000,
    B01010000,
    B00100000,
    B00000000,

    B00000000,  //w
    B00000000,
    B10001000,
    B10101000,
    B10101000,
    B10101000,
    B01010000,
    B00000000,

    B00000000,  //x
    B00000000,
    B10001000,
    B01010000,
    B00100000,
    B01010000,
    B10001000,
    B00000000,

    B00000000,  //y
    B00000000,
    B10001000,
    B10001000,
    B01111000,
    B00001000,
    B01110000,
    B00000000,

    B00000000,  //z
    B00000000,
    B11111000,
    B00010000,
    B00100000,
    B01000000,
    B11111000,
    B00000000,

    B00100000,  //{
    B01000000,
    B01000000,
    B10000000,
    B01000000,
    B01000000,
    B00100000,
    B00000000,

    B10000000,  //|
    B10000000,
    B10000000,
    B10000000,
    B10000000,
    B10000000,
    B10000000,
    B00000000,

    B10000000,  //}
    B01000000,
    B01000000,
    B00100000,
    B01000000,
    B01000000,
    B10000000,
    B00000000,

    B00000000,  //~
    B00000000,
    B00000000,
    B01101000,
    B10010000,
    B00000000,
    B00000000,
    B00000000,

    B01100000,  // (Char 0x7F)
    B10010000,
    B10010000,
    B01100000,
    B00000000,
    B00000000,
    B00000000,
    B00000000
};

void scrollFont() {
    for (int counter=0x20;counter<0x80;counter++){
        loadBufferLong(counter);
        delay(500);
    }
}

// Scroll Message
void scrollMessage(const unsigned char * messageString) {
    int counter = 0;
    int myChar=0;
    do {
        // read back a char
        myChar =  pgm_read_byte_near(messageString + counter);
        if (myChar != 0){
            loadBufferLong(myChar);
        }
        counter++;
    }
    while (myChar != 0);
}
// Load character into scroll buffer
void loadBufferLong(int ascii){
    if (ascii >= 0x20 && ascii <=0x7f){
        for (int a=0;a<8;a++){                      // Loop 7 times for a 5x7 font
            unsigned long c = pgm_read_byte_near(font5x7 + ((ascii - 0x20) * 8) + a);     // Index into character table to get row data
            unsigned long x = bufferLong [a*2];     // Load current scroll buffer
            x = x | c;                              // OR the new character onto end of current
            bufferLong [a*2] = x;                   // Store in buffer
        }
        //byte count = pgm_read_byte_near(font5x7 +((ascii - 0x20) * 9) + 8);     // Index into character table for kerning data
        int count = trim_matrix(font5x7 + ((ascii - 0x20) * 8));
        //byte count = 6;
        for (int x=0; x<count;x++){
            rotateBufferLong();
            printBufferLong();
            delay(scrollDelay);
        }
    }
}
// Rotate the buffer
void rotateBufferLong(){
    for (int a=0;a<8;a++){                      // Loop 7 times for a 5x7 font
        unsigned long x = bufferLong [a*2];     // Get low buffer entry
        byte b = bitRead(x,31);                 // Copy high order bit that gets lost in rotation
        x = x<<1;                               // Rotate left one bit
        bufferLong [a*2] = x;                   // Store new low buffer
        x = bufferLong [a*2+1];                 // Get high buffer entry
        x = x<<1;                               // Rotate left one bit
        bitWrite(x,0,b);                        // Store saved bit
        bufferLong [a*2+1] = x;                 // Store new high buffer
    }
}
// Display Buffer on LED matrix
void printBufferLong(){
  for (int a=0;a<8;a++){                    // Loop 7 times for a 5x7 font
    unsigned long x = bufferLong [a*2+1];   // Get high buffer entry
    byte y = x;                             // Mask off first character
    lc.setRow(3,a,y);                       // Send row to relevent MAX7219 chip
    x = bufferLong [a*2];                   // Get low buffer entry
    y = (x>>24);                            // Mask off second character
    lc.setRow(2,a,y);                       // Send row to relevent MAX7219 chip
    y = (x>>16);                            // Mask off third character
    lc.setRow(1,a,y);                       // Send row to relevent MAX7219 chip
    y = (x>>8);                             // Mask off forth character
    lc.setRow(0,a,y);                       // Send row to relevent MAX7219 chip
  }
}