Was upgrading firmware and now device is not booting anymore. Monitor connected via VGA shows nothing. Tried TFTP tool, but it not managing connect to device.
Any suggestion?
The next level approach to determine the cause of the problem would be to connect to the serial console.
Requires:
USB to TTL serial adaptor, PL2303HX-based work OK.
4-pin ZH JST 1.5mm wired connector.