const int dataPin = 8;   // DS
const int latchPin = 9;  // STCP
const int clockPin = 10; // SHCP

void setup() {
  pinMode(dataPin, OUTPUT);
  pinMode(latchPin, OUTPUT);
  pinMode(clockPin, OUTPUT);
}

void loop() {
  // Turn on the LED at position (1,1)
  clearLEDs(); // First, clear the display
  //setLED(1, 1, HIGH); // Set the LED at position (1,1) to ON
  // No need to call refreshDisplay() since setLED() already updates the display
  delay(1000); // Keep the LED on for 1000 milliseconds (1 second)
}

void clearLEDs() {
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, MSBFIRST, 0x00); // Clear columns
  shiftOut(dataPin, clockPin, MSBFIRST, 0x00); // Clear rows
  digitalWrite(latchPin, HIGH);
}

void setLED(int row, int col, boolean state) {
  byte rowBit = 0x01 << row; // Determine the row bit to turn on
  byte colBit = ~(0x01 << col); // Determine the column bit to turn on, invert because common anode

  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, MSBFIRST, colBit); // Set columns
  shiftOut(dataPin, clockPin, MSBFIRST, rowBit); // Set rows
  digitalWrite(latchPin, HIGH);
}

void shiftRegisterWrite(byte data) {
  // Function to write data to a shift register
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, MSBFIRST, data);
  digitalWrite(latchPin, HIGH);
}