[quote user="Martin Held"]Ah-hah, so there *is* an IO block that's powered by VBUS, and without power to VBUS, that block will never operate then?[/quote]
Well, how is the controller supposed to send out the 5V USB data signals for the enumeration, when there is no 5V supply? It won’t generate the voltage (and the required current) from MSP 3.3V