// This version uses bit-banged SPI.
// If you see tearing (jagged edges on the circles) try the version
// which uses AVR's hardware SPI peripheral:
// https://wokwi.com/arduino/projects/318868939929027156

#define CLK1 9
#define DIN1 11
#define CS  10
#define CLK2 8
#define DIN2 12

byte background[16][8];

byte letter_A[8]={0b00000000,
                  0b00011000,
                  0b00100100,
                  0b10000001,
                  0b10000001,
                  0b11111111,
                  0b10000001,
                  0b10000001,
                };

byte scren[16][8]={0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 
                   0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000
                  };


void shiftAll(byte send_to_address, byte send_this_data)
{
  digitalWrite(CS, LOW);
  for (int SEGMENTS = 0; SEGMENTS <8;SEGMENTS++) {
    shiftOut(DIN1, CLK1, MSBFIRST, send_to_address);
    shiftOut(DIN1, CLK1, MSBFIRST, send_this_data);
    shiftOut(DIN2, CLK2, MSBFIRST, send_to_address);
    shiftOut(DIN2, CLK2, MSBFIRST, send_this_data);
  }
  digitalWrite(CS, HIGH);
}

void display_scren(){
          
  for (int segmen_width = 0; segmen_width<8;segmen_width++) {
       digitalWrite(CS, LOW);
  for (int segmen_length = 0; segmen_length<8;segmen_length++) {
      
      int segmen_width2 =(segmen_width+8);     
      shiftOut(DIN1, CLK1, MSBFIRST,segmen_width+1);
      shiftOut(DIN1, CLK1, LSBFIRST, scren[segmen_width][segmen_length]);
      shiftOut(DIN2, CLK2, MSBFIRST,segmen_width+1);
      shiftOut(DIN2, CLK2, LSBFIRST,scren[segmen_width2][segmen_length]);
  } 
   digitalWrite(CS, HIGH);
  }
  


}


void setup() {
  Serial.begin(115200);
  pinMode(CLK1, OUTPUT);
  pinMode(DIN1, OUTPUT);
  pinMode(CS, OUTPUT);
  
  pinMode(CLK2, OUTPUT);
  pinMode(DIN2, OUTPUT);

  // Setup each MAX7219
  shiftAll(0x0f, 0x00); //display test register - test mode off
  shiftAll(0x0b, 0x07); //scan limit register - display digits 0 thru 7
  shiftAll(0x0c, 0x01); //shutdown register - normal operation
  shiftAll(0x0a, 0x0f); //intensity register - max brightness
  shiftAll(0x09, 0x00); //decode mode register - No decode

  //shiftAll(0x01, 0x01);
  for(int i=0; i<8; i++){
    for(int j=0; j<8; j++){
      byte pixcel = bitRead(letter_A[i], j);
           bitWrite(scren[i][1], j, pixcel);
    }
    
  }
  
}


void loop() {
display_scren();
}
void write_pixcel(int x, int y, byte pixcel){
  bitWrite(scren[][], )
}