code: @Override
      public byte[] toByteArray() {
          ByteArrayOutputStream outputStream = new ByteArrayOutputStream(16);
  
          outputStream.write(commandByte);
          outputStream.write(sysexCommandByte);
  
          if (serialize(outputStream)) {
              outputStream.write(CommandBytes.END_SYSEX.getCommandByte());
              return outputStream.toByteArray();
          }
  
          return null;
      }
docs: Combine the SysexCommandByte and the serialized sysex message packet together to form a Firmata supported
  sysex byte packet to be sent over the SerialPort.
  
  @return byte[] array representing the full Firmata sysex command packet to be sent to the Firmata device.