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73416ba
(Get the code!)
I was trying to power my Panda board from USB OTG connector, it dies early in boot apparently in xloader or u-boot when connected to a laptop.
I did three tests
1) Short the USB OTG 5V pin to the DC Jack 5V pin in case something in the OTG 5V path makes trouble. It still dies in early boot.
2) Remove the D+ and D- wires from the USB cable, still plugged into the OTG socket. It still dies in early boot.
3) Completely remove the connection from the OTG socket, and bring the same laptop USB power to the DC power jack. Boots fine.
So it seems that you just need external power coming to the OTG power pin to make the early boot problem.
I also tested combinations of DC Jack power with OTG power using different sequencing, DC Jack power couldn't allow it to recover once it was in the process of dying, and you could not start the board again until both power sources were removed.