OK, thank you for quick answers. I will try UART boot on functional one. But I think I can remember that is has a bootCode version 1.11, so I am not lucky at this one. Sure, that ideas came across my mind and I have already tried to find some information about JTAGing this board. But, since this is not exactly the same board as QNAP TS-219 has I can never be sure about any informations Iby Hy3n4 - uBoot
Hi bodhi and thank you for your reply. Unfortunately I can see nothing more than "Sending boot message. Please reboot the target.../" and TX led on UART is blinking like crazy. So it probably tries to send boot code but no one is responding on the other side. I thought about trying UART boot on second working box but I'm a bit scared because I don't want to end up with tby Hy3n4 - uBoot