68k program header

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ASM ROM header templates.

For cartridge systems

Address Size Description
$100 7 bytes "NEO-GEO" string (first cartridge recognition code)
$107 byte System version (0 for cartridge systems, 1 or 2 for adapted cart games on Neo CD ?)
$108 word NGH number, 0000 prohibited
$10A longword Program size in bytes
$10E longword Pointer to backup RAM block (in 68k user RAM), first 2 bytes are debug dips.
$112 word Size of the game save in bytes
$114 byte Eye-catcher animation flag. 0=Done by BIOS, 1=Done by game, 2=Nothing
$115 byte Sprite bank number (upper 8 bits of tile number) for the eye-catcher logo, if done by BIOS
$116 longword Pointer to Japanese software DIPs settings layout
$11A longword Pointer to US settings software DIPs settings layout
$11E longword Pointer to Euro settings software DIPs settings layout
$122 6 bytes JMP to USER subroutine (code start)
$128 6 bytes JMP to PLAYER_START subroutine
$12E 6 bytes JMP to DEMO_END subroutine
$134 6 bytes JMP to COIN_SOUND subroutine
$182 longword Pointer to security code (second cartridge recognition code)
$186 longword Unknown (seems only set to 0x00000000 on boards containing Spanish software DIPs)
$18A longword Unknown (seems only set to 0x00000001 on boards containing Spanish software DIPs)
$18E longword Pointer to Spanish settings software DIPs settings layout (not all games use this)

Minimal header (from Smkdan's sources)

No need for a complete 68k vector table.

	org $0000
	dc.l $10F300

	org $0004
	dc.l $C00402

	org $0064
	dc.l VBLANK	;IRQ handler

	org $0100
	dc.b "NEO-GEO",$00

	org $0108
	dc.w $1234	;NGH

	org $0122
	jmp USER	;entry

	org $0114
	dc.w $0100	;logo flag, don't show it just go straight to the entry point

	org $0182
	dc.l Code	;code pointer
Code:
	dc.l $76004A6D,$0A146600,$003C206D,$0A043E2D
	dc.l $0A0813C0,$00300001,$32100C01,$00FF671A
	dc.l $30280002,$B02D0ACE,$66103028,$0004B02D
	dc.l $0ACF6606,$B22D0AD0,$67085088,$51CFFFD4
	dc.l $36074E75,$206D0A04,$3E2D0A08,$3210E049
	dc.l $0C0100FF,$671A3010,$B02D0ACE,$66123028
	dc.l $0002E048,$B02D0ACF,$6606B22D,$0AD06708
	dc.l $588851CF,$FFD83607
	dc.w $4e75

Full header (from some unknown example code)

    org $0100
    dc.b "NEO-GEO",$00

    dc.w $1234        ;NGH
    dc.l $00080000    ;P ROM size
    dc.l $00100000    ;debug DIPs pointer
    dc.w $01          ;size of DIP data
    dc.b $00          ;let the BIOS show the logo
    dc.b $1B          ;first tile of the logo is $1B00
    dc.l JPConfig     ;Japanese config menu pointer
    dc.l USConfig     ;US config menu pointer
    dc.l EUConfig     ;European config menu pointer

    jmp        USER
    jmp        PLAYER_START
    jmp        DEMO_END
    jmp        COIN_SOUND

    org $0182
    dc.l Code         ;code pointer
Code:
    dc.l $76004A6D,$0A146600,$003C206D,$0A043E2D
    dc.l $0A0813C0,$00300001,$32100C01,$00FF671A
    dc.l $30280002,$B02D0ACE,$66103028,$0004B02D
    dc.l $0ACF6606,$B22D0AD0,$67085088,$51CFFFD4
    dc.l $36074E75,$206D0A04,$3E2D0A08,$3210E049
    dc.l $0C0100FF,$671A3010,$B02D0ACE,$66123028
    dc.l $0002E048,$B02D0ACF,$6606B22D,$0AD06708
    dc.l $588851CF,$FFD83607
    dc.w $4e75

    ; Configuration menu layouts (soft DIPs)
 JPConfig:
    dc.b    "0123456789ABCDEF"                            ; Game name
    dc.b    $FF,$FF,$FF,$FF,$FF,$FF                       ; Special list
    dc.b    $24,$02,$00,$00,$00,$00,$00,$00,$00,$00       ; Option list
    dc.b    "LIVES       "
    dc.b    "1           "
    dc.b    "2           "
    dc.b    "3           "
    dc.b    "4           "
    dc.b    "HOW TO PLAY "
    dc.b    "WITH        "
    dc.b    "WITHOUT     "

 USConfig:
    dc.b    "0123456789ABCDEF"                            ; Game name
    dc.b    $FF,$FF,$FF,$FF,$FF,$FF                       ; Special list
    dc.b    $24,$02,$00,$00,$00,$00,$00,$00,$00,$00       ; Option list
    dc.b    "LIVES       "
    dc.b    "1           "
    dc.b    "2           "
    dc.b    "3           "
    dc.b    "4           "
    dc.b    "HOW TO PLAY "
    dc.b    "WITH        "
    dc.b    "WITHOUT     "

 EUConfig:
    dc.b    "0123456789ABCDEF"                            ; Game name
    dc.b    $FF,$FF,$FF,$FF,$FF,$FF                       ; Special list
    dc.b    $24,$02,$00,$00,$00,$00,$00,$00,$00,$00       ; Option list
    dc.b    "LIVES       "
    dc.b    "1           "
    dc.b    "2           "
    dc.b    "3           "
    dc.b    "4           "
    dc.b    "HOW TO PLAY "
    dc.b    "WITH        "
    dc.b    "WITHOUT     "

For CD systems

    org     $100
    dc.b    "NEO-GEO",$02           ;CDDA flag
    dc.w    $1234                   ;NGH
    dc.l    $00080000               ;P ROM size
    dc.l    $00100000               ;debug DIPs pointer
    dc.w    $01                     ;size of DIP data
    dc.b    $00                     ;let the BIOS show the logo
    dc.b    $1B                     ;first tile of the logo is $1B00
    dc.l    JPConfig                ;Japanese config menu pointer
    dc.l    USConfig                ;US config menu pointer
    dc.l    EUConfig                ;European config menu pointer

    org     $122
    jmp     Start

    org     $13A
    dc.w    $0000                   ;Z80 RAM address for CDDA commands