#include <SPI.h>
int latchPin1 = 12;      // (11) ST_CP [RCK] on 74HC595
int clockPin1 = 11;      // (9) SH_CP [SCK] on 74HC595
int dataPin1 = 13;     // (12) DS [S1] on 74HC595
int latchPin2 = 9;      // (11) ST_CP [RCK] on 74HC595
int clockPin2 = 8;      // (9) SH_CP [SCK] on 74HC595
int dataPin2 = 10;     // (12) DS [S1] on 74HC595
int latchPin3 = 6;      // (11) ST_CP [RCK] on 74HC595
int clockPin3 = 5;      // (9) SH_CP [SCK] on 74HC595
int dataPin3 = 7;     // (12) DS [S1] on 74HC595
int latchPin4 = 3;      // (11) ST_CP [RCK] on 74HC595
int clockPin4 = 2;      // (9) SH_CP [SCK] on 74HC595
int dataPin4 = 4;     // (12) DS [S1] on 74HC595

byte ledData[4] = {0}; // Array to store data for each row (4 bytes)

void setup() {
  // Set data, clock, and latch pins as outputs
  pinMode(dataPin1, OUTPUT);
  pinMode(clockPin1, OUTPUT);
  pinMode(latchPin1, OUTPUT);
  pinMode(dataPin2, OUTPUT);
  pinMode(clockPin2, OUTPUT);
  pinMode(latchPin2, OUTPUT);
  pinMode(dataPin3, OUTPUT);
  pinMode(clockPin3, OUTPUT);
  pinMode(latchPin3, OUTPUT);
  pinMode(dataPin4, OUTPUT);
  pinMode(clockPin4, OUTPUT);
  pinMode(latchPin4, OUTPUT);
}

void loop() {
  // Turn on specific LEDs in each row
  ledData[1] = 0b00100110;
  ledData[2] = 0b11100010; 
  ledData[3] = 0b01010101;
  ledData[4] = 0b01000111;

  // Send data to all shift registers
  for (int i = 0; i < 4; i++) {
    shiftOut(ledData[1]);
    shiftOut2(ledData[2]);
    shiftOut3(ledData[3]);
    shiftOut4(ledData[4]);
  }
  digitalWrite(latchPin1, HIGH);
  digitalWrite(latchPin2, HIGH); 
  digitalWrite(latchPin3, HIGH);
  digitalWrite(latchPin4, HIGH);
  
  // Delay (optional, adjust as desired)

}

void shiftOut(byte data) {
  digitalWrite(latchPin1, LOW);
  for (int i=7; i>=0; i--) {
    digitalWrite(dataPin1, bitRead(data, i));
    digitalWrite(clockPin1, HIGH);
    digitalWrite(clockPin1, LOW);
  }
  digitalWrite(latchPin1, HIGH);
}
void shiftOut2(byte data2) {
  digitalWrite(latchPin2, LOW);
  for (int i=7; i>=0; i--) {
    digitalWrite(dataPin2, bitRead(data2, i));
    digitalWrite(clockPin2, HIGH);
    digitalWrite(clockPin2, LOW);
  }
  digitalWrite(latchPin2, HIGH);
}
void shiftOut3(byte data3) {
  digitalWrite(latchPin3, LOW);
  for (int i=7; i>=0; i--) {
    digitalWrite(dataPin3, bitRead(data3, i));
    digitalWrite(clockPin3, HIGH);
    digitalWrite(clockPin3, LOW);
  }
  digitalWrite(latchPin3, HIGH);
}
void shiftOut4(byte data4) {
  digitalWrite(latchPin4, LOW);
  for (int i=7; i>=0; i--) {
    digitalWrite(dataPin4, bitRead(data4, i));
    digitalWrite(clockPin4, HIGH);
    digitalWrite(clockPin4, LOW);
  }
  digitalWrite(latchPin4, HIGH);
}