System ROM

BIOSes are ROMs containing the initial program executed by NeoGeo systems. They are present in all hardware types.

AES BIOS
128kB. NEO-EP0.

MVS BIOS
128kB. SP-S2. Different names according to nationality.

RAM locations

 * $10FD80: ?
 * $10FD83: Nationality (JP:0, EN:1, EU:2, goes up to 6 ?)

The NeoGeo CD (not CDZ) BIOS contains credits, organized to be displayed on the fix layer (how can this be seen on screen ?):

CREDITS SOFTWARE NORIYUKI HIGASHI HARDWARE MOTOO YOKOYAMA TOSHIYA YAHARA GRAPHICS OTIAI SPECIAL JON   GUSO THANKS  CURRY SHIMIZU SNK ALL STAFF

Noriyuki Higashi = Mr.Noric



1MiB chip that contains Z80 and 68k programs, PCM sound, and graphics which are copied to the corresponding DRAMs at boot time.

Graphic visualisation of a CDZ BIOS dump, with separated data blocks (larger size available):