MemberMarch 9, 2020 at 12:22 pm
to be honest I am more surprised that the first two MEGAs use the same COM port number.
Because typically each new device is assigned with a new COM port number. To be precise – this may be configured in the operating system settings – if a new device with the same PID/VID gets the same or a new COM port number.
Please check how it is recognized by the operating system (Device Manager in Windows). As Arduino Mega?