-- 68008 --		--- 68000 ---		---- 68020+ ----
Max. RAM	00000-BFFFF 768k	000000-FBFFFF 16128k	00000000-FFFBFFFF 4G
FlashROM	C0000-DFFFF 128k	FC0000-FDFFFF 128k	FFFC0000-FFFDFFFF 128k
I/O (TUBE)	E0000-EFFFF 64k		FE0000-FEFFFF 64k	FFFE0000-FFFEFFFF 64k
Host memory	FF000-FFFFF 64k		FF0000-FFFFFF 64k	FFFF0000-FFFFFFFF 64k

AAAA AAAA
1111 1111
9876 5432
---- ----
1110 xxxx = TRUE: FlashROM/IO
1110 xxxx = FALSE: RAM, bank select by A19

1111 1111 = TRUE: I/O
1111 1111 = FALSE: FlashROM/RAM