I was under impression that the four-port mode was not supported on any of the currently available chips. Apparently it is. There are new registers in the U version that allow to use ports E/F instead of the missing L.
I want non-multiplexed SRAM. Anybody tried that? Any words of wisdom?
EDIT: Well, I tried this on atxmega64a1u on STK600. Without actual SRAM yet. The micro seems to generate all the right signals needed to address up to 16MB of SRAM. That is encouraging.
I wish Atmel would fix the documentation! We need a new version of AVR1312 for the U versions. Need to say something about the EBIOUT in the non-U to U migration guide. The max EBI mode is more like four-and-half-port, rather than just four-port ... unless I'm still missing something.