Hello LVD, I'm not an C++ programmer and there is a lot I don't understand so this question is for you. Please, i hope to use my FLSun in the coming days but now the firmware is not working as wanted After download and compiling your version, my first compilation went well, but after putting my active serial port it went wrong??? * Select which serial port on the board will be used for communiby joepw - Delta Machines