some changes while testing with arduino

UsbHidTestApp/Program.cs

@@ -113,7 +113,9 @@ internal class Program
                         else
                         {
                             byte[] msgBytes = Encoding.ASCII.GetBytes(message!);
-                            List<byte> listBytes = msgBytes.ToList();
+                            List<byte> listBytes = new List<byte>();
+                            listBytes.Add((byte)' ');  // temp fix for first sign wrong
+                            listBytes.AddRange(msgBytes);
                             listBytes.Add((byte)'\n');
                             _device.Write(listBytes.ToArray());
                         }
@@ -176,8 +178,11 @@ internal class Program
                     string print = Encoding.UTF8.GetString(readData.Data);
                     //print = print.Replace("\r", "").Replace("\n", "");  // Newline Mode: none
                     //print = print.Replace("\r", "");  // Newline Mode: only print \n
-                    //print = print.Replace("\n", "");  // Newline Mode: only print \r
-                    Console.Write(print);
+                    print = print.Replace("\0", "");  // delete null chars
+                    if(String.IsNullOrEmpty(print) == false)
+                    {
+                        Console.Write(print);
+                    }
                 }
             }
             catch (TimeoutException) { }