Hello. We are prototyping a design for our new AT91SAM9261 and keep thinking of new things we need to talk serial to. We are at 7 and counting.

The problem of course is that the 9261 only has four UARTs (counting DBGU).

I am new to the 9261 but am impressed with the configurability, the PIO system, etc. So I want to ask: is there some sneaky way to maybe internally multiplex additional pins into the UART, so that functionally we can (bidirectionally) interface with more than 4 external serial components.

The other solutions are all pretty ugly (soft UART, a slave processor with additional UARTs), so I thought I'd ask if there is anything clever the 9261 can do internally that might help us here.

Thanks for any thoughts.