Arduino serial hex decimal values code
A possible implementation of the protocol using serial read/write of binary data (command and response).

void send(Stream&amp; ios, uint8_t cmd[6])
{
  uint8_t sum = 0;
  for (int i = 0; i &lt; 6; i++) {
    uint8_t c = cmd[i];
    sum += c;
    ios.print((char) c);
  }
  ios.print((char) sum);
}

bool recv(Stream&amp; ios, uint8_t res[6])
{
  uint8_t sum = 0;
  uint8_t c;
  for (int i = 0; i &lt; 6; i++) {
    while (!ios.available());
    c = ios.read();
    sum += c;
    res[i] = c;
  }
  while (!ios.available());
  c = ios.read();
  return (sum == c);
}

void setup()
{
  Serial.begin(57600);
  while (!Serial);

  uint8_t cmd[] = { 0xB4, 0xC0, 0xA8, 0x01, 0x01, 0x00 };
  uint8_t res[6];
  send(Serial, cmd);
  recv(Serial, res);
}

void loop()
{
}


Cheers!