// Bağlantılar
const int clkPin = 11; // CLK pini
const int dioPin = 12; // DIO pini
const byte rowPins[] = {9, 8, 7, 6}; // Keypad row pinleri
const byte colPins[] = {5, 4, 3, 2}; // Keypad column pinleri

char keys[4][4] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

char nums[4] = {'0', '0', '0', '0'};
int digitIndex = 0;

void setup() {
 pinMode(clkPin, OUTPUT);
  pinMode(dioPin, OUTPUT);
  for (int i = 0; i < 4; i++) {
    pinMode(rowPins[i], INPUT_PULLUP);
  }
  for (int i = 0; i < 4; i++) {
    pinMode(colPins[i], OUTPUT);
    digitalWrite(colPins[i], HIGH);
  }
  tm1637Init();
  for (int i = 0; i < 4; i++) {
    tm1637DisplayDigit(i, nums[i] - '0');
  }
 int i = 0;
}

void loop() {
  char key = getKey();
  if (isdigit(key)) {
    nums[digitIndex] = key;
    tm1637DisplayDigit(digitIndex, key - '0');
    digitIndex = (digitIndex + 1) % 4;
  } 
   if (key == '#') {
  
    tm1637DisplayDigit(0, ' ');
  } 
   if (key == '*') {
     for (int i = 0; i < 4; i++) {
      tm1637DisplayDigit(i, '1');
      nums[i]=0;
    }
    digitIndex=0;
  }
  
}


char getKey() {
  for (int i = 0; i < 4; i++) {
    digitalWrite(colPins[i], LOW);
    for (int j = 0; j < 4; j++) {
      if (digitalRead(rowPins[j]) == LOW) {
        delay(10);
        char key = keys[j][i];
        digitalWrite(colPins[i], HIGH);
        return key;
      }
    }
    digitalWrite(colPins[i], HIGH);
  }
  return 0;
}

void tm1637Start() {
  digitalWrite(clkPin, HIGH);
  digitalWrite(dioPin, HIGH);
  digitalWrite(dioPin, LOW);
  digitalWrite(clkPin, LOW);
}

void tm1637Stop() {
  digitalWrite(clkPin, LOW);
  digitalWrite(dioPin, LOW);
  digitalWrite(clkPin, HIGH);
  digitalWrite(dioPin, HIGH);
}

void tm1637WriteByte(uint8_t data) {
  for (uint8_t i = 0; i < 8; i++) {
    digitalWrite(clkPin, LOW);
    if (data & 0x01) {
      digitalWrite(dioPin, HIGH);
    } else {
      digitalWrite(dioPin, LOW);
    }
    data >>= 1;
    digitalWrite(clkPin, HIGH);
  }
  digitalWrite(clkPin, LOW);
  digitalWrite(dioPin, HIGH);
  digitalWrite(clkPin, HIGH);
  digitalWrite(dioPin, LOW);
}

void tm1637DisplayDigit(uint8_t digit, uint8_t value) {
  uint8_t segmentData = 0;
  if (value != 0x7F) {
    segmentData = tm1637DigitToSegment(value);
  }
  tm1637Start();
  tm1637WriteByte(0x44); // Data Write for 1st digit + Address
  tm1637Stop();
  tm1637Start();
  tm1637WriteByte(0xC0 + digit); // Auto Address Increment (00-07) + Address
  tm1637WriteByte(segmentData);
  tm1637Stop();
}

void tm1637DisplayAll() {
  for (uint8_t digit = 0; digit < 4; digit++) {
    tm1637DisplayDigit(digit, nums[digit] - '0');
  }
}

void tm1637Init() {
  tm1637Start();
  tm1637WriteByte(0x8a); // Display Control Set (8x - 1/16)
  tm1637Stop();
  tm1637Start();
  tm1637WriteByte(0x40); // Data Command (Write Data)
  tm1637Stop();
}

uint8_t tm1637DigitToSegment(uint8_t digit) {
  static const uint8_t digitToSegment[] = {
    0x3F, // 0
    0x06, // 1
    0x5B, // 2
    0x4F, // 3
    0x66, // 4
    0x6D, // 5
    0x7D, // 6
    0x07, // 7
    0x7F, // 8
    0x6F, // 9
    0x40  // Blank
  };
  return digitToSegment[digit];
}