MCB2140 USB multiple interrupts

On the MCB2140 board the USB HID example runs fine, in order to understand code flow, I enabled UART0 to be my debug port. When I attempt to DebugOut text during USB transactions, my DebugOut routine gets one character out then freezes. I've tried switching the priority using VicVectCntl
with no success. Any ideas appreciated.

More questions in this forum