)
Values for switch settings on original EGA/VGA:
 00h		primary MDA/HGC,	secondary EGA+ 40x25
 01h-03h	primary MDA/HGC,	secondary EGA+ 80x25
 04h		primary CGA 40x25,	secondary EGA+ 80x25 mono
 05h		primary CGA 80x25,	secondary EGA+ 80x25 mono
 06h		primary EGA+ 40x25,	secondary MDA/HGC (optional)
 07h-09h	primary EGA+ 80x25,	secondary MDA/HGC (optional)
 0Ah		primary EGA+ 80x25 mono,secondary CGA 40x25 (optional)
 0Bh		primary EGA+ 80x25 mono,secondary CGA 80x25 (optional)