PE=0, no protection events.
Dbit=0, USE16 code

The CWRmode, Canonical Wake-up Real Mode, stuff is in here, along with any
variants I use, if any.

With 8086 limits this is CWR Mode. With bigger limits it's not much
different. With a non-0 CS base I dono. Then it's starting to look like
INTeL V86 mode, without paging or tasks. Hmmmmmm.


