[knc1]

Originally Posted by dalvick

hello, thank you for answers
i use this without external power
http://www.ebay.fr/itm/RS232-To-TTL-...-/252399950706



and do the same think when i unplug 5v cable and use external!

terminal reset dont resolve it and with tera term ger the same issue

Wrong interface voltage, that adapter is not for 1.8 volt, low voltage, ttl serial.
That is a RS-232 (12 volt interface) adapter.

It is very likely that you have destroyed the serial port in the SoC.

Disconnect that thing and get the proper adapter.
If your very lucky, the SoC might still work.