Please add basic.bbc and newos.bbc files here.

basic.bbc = 0x8000-0xbfff
newos.bbc = 0xc000-0xffff
(don't worry about the odd bit of memory mapped IO here ;-)
If things don't work, then a 'state' of memory mapped io that appears to can
be found in mmap.bbc. This is 0xfc00-0xffff.
