Arduino stream deck for price of "next to nothing"

uint8_t buf[8] = {
  0
};  // Keyboard Report Buffer: 8 bytes

#define B1 12
#define B2 11
#define B3 10
#define B4 9
#define B5 8
#define B6 7

//#define SERIAL_DEBUG  // for serial debug: remove //
                        // for actual HID: put //
int state = 1;

void setup()
{
  Serial.begin(9600);
  pinMode(B1, INPUT);
  pinMode(B2, INPUT);
  pinMode(B3, INPUT);
  pinMode(B4, INPUT);
  pinMode(B5, INPUT);
  pinMode(B6, INPUT);
  // enable internal pull-ups
  digitalWrite(B1, 1);
  digitalWrite(B2, 1);
  digitalWrite(B3, 1);
  digitalWrite(B4, 1);
  digitalWrite(B5, 1);
  digitalWrite(B6, 1);

  delay(200);
}
//we are using hex 0xseries
void loop()
{
  state = digitalRead(B1);
  if (state != 1) {
    buf[2] = 0x68;    // f13 or 104
    Serial.write(buf, 8); // Send keypress
    releaseKey();
  }

  state = digitalRead(B2);
  if (state != 1) {
    buf[2] = 0x69;   // f14 or 105
    Serial.write(buf, 8); // Send keypress
    releaseKey();
  }

  state = digitalRead(B3);
  if (state != 1) {
    buf[2] = 0x6A;   // f15 key or 106
    Serial.write(buf, 8); // Send keypress
    releaseKey();
  }

    state = digitalRead(B4);
  if (state != 1) {
    buf[2] = 0x6B;    // f16 key or 107
    Serial.write(buf, 8); // Send keypress
    releaseKey();
  }

  state = digitalRead(B5);
  if (state != 1) {
    buf[2] = 0x6C;   // f17 key or 108
    Serial.write(buf, 8); // Send keypress
    releaseKey();
  }

  state = digitalRead(B6);
  if (state != 1) {
    buf[2] = 0x6D;   // f18 key or 109
    Serial.write(buf, 8); // Send keypress
    releaseKey();
  }
}

void releaseKey()
{
  delay(200);
  buf[0] = 0;
  buf[2] = 0;
  Serial.write(buf, 8); // Release key
}