In the menuconfig system I looked for a way to get an NSH prompt on UART2,
but didn't find it. Is there a way to do that? If so, how? Or can I put an
NSH prompt on a USB interface?
I mentioned that but I thought you wanted to use the CDC/ACM serial port
on the AVR32. If you want to use UART2, that answer is the same except
that n=2 and 115,200 baud should be okay.
When you said USB, were you talking about the CDC/ACM in the AVR32?
That was not clear. that is easy per the preceding response. Getting a
true USB port directly to the SAMA5D27 is a lot more complex.
The place to look in the configuration menus is drivers -> serial.
If you ever get lost in the configurations, type '/'. A menu will come
up an you can use it find configuration items in the menu tree and also
any dependencies needed.