sa1regs.asm

linux下的任天堂模拟器代码。供大家参考。

;Copyright (C) 1997-2007 ZSNES Team ( zsKnight, _Demo_, pagefault, Nach )
;
;http://www.zsnes.com
;http://sourceforge.net/projects/zsnes
;https://zsnes.bountysource.com
;
;This program is free software; you can redistribute it and/or
;modify it under the terms of the GNU General Public License
;version 2 as published by the Free Software Foundation.
;
;This program is distributed in the hope that it will be useful,
;but WITHOUT ANY WARRANTY; without even the implied warranty of
;MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;GNU General Public License for more details.
;
;You should have received a copy of the GNU General Public License
;along with this program; if not, write to the Free Software
;Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.


; SA-1 emulation.  Information provided by Ivar of Snes9x.
;    coded by zsKnight
; SDD-1 emulation.  SDD-1 MMC reverse engineered by zsKnight,
;    SDD-1 decompress Dark Force and John Weidman,


; - Add MMC support
; - Add end of DMA IRQ support
; - Add Char Conversion #1
; - Add Char Conversion #2
; - Add Memory Disables (Guess this isn't needed)
; IRQs - IRQ Clear (also clear 2300), IRQ Disable, and IRQ Enable

; Mario RPG Level-up not working - it was using one of the IRQ functions
;   that no other place in the game is using, which I suppose is the cause
;   of the problem, but it's been so long since I worked on SA-1, that
;   I forgot which part.

%include "macros.mac"

EXTSYM regptr,regptw,romdata,SA1Status,SDD1BankA,NumofBanks,BWUsed2
EXTSYM Get_Time,Get_TimeDate,irqv2,irqv,nmiv2,nmiv,snesmmap,snesmap2
EXTSYM curypos,CurrentExecSA1,memaccessbankr8sdd1,memtabler8,AddrNoIncr

%ifndef NO_DEBUGGER
EXTSYM debuggeron,debstop4
%endif

%include "cpu/regs.mac"
%include "cpu/regsw.mac"

SECTION .data
NEWSYM RTCData, db 0Fh,0,0,0,0,0,0,0,0,0,0,0,0,0,0Fh,0
NEWSYM RTCPtr, dd 0
NEWSYM RTCPtr2, dd 0
NEWSYM RTCRest, dd 0

SECTION .text

RTC2800:
    push ebx
    cmp dword[RTCRest],100
;    je .go
;    inc dword[RTCRest]
;    jmp .notfirst
.go
    cmp dword[RTCPtr],0
    jne near .notfirst
%ifndef NO_DEBUGGER
    cmp byte[debuggeron],1
    je near .notfirst
%endif
    ; fill time/date
    push ebx
    push eax
    call Get_Time
    mov bl,al
    and bl,0Fh
    mov [RTCData+1],bl  ; seconds
    shr eax,4
    mov bl,al
    and bl,0Fh
    mov [RTCData+2],bl
;    jmp .done
    shr eax,4
    cmp word[RTCData+1],0
;    jne .notminch
    mov bl,al
    and bl,0Fh
    mov [RTCData+3],bl  ; minutes
    shr eax,4
    mov bl,al
    and bl,0Fh
    mov [RTCData+4],bl
.notminch
;    jmp .done
    shr eax,4
    mov bl,al
    and bl,0Fh
    mov [RTCData+5],bl  ; hours
    shr eax,4
    mov bl,al
    and bl,0Fh
    mov [RTCData+6],bl
    call Get_TimeDate
    mov bl,al
    and bl,0Fh
    mov [RTCData+7],bl  ; day
    shr eax,4
    mov bl,al
    and bl,0Fh
    mov bl,al
    and bl,0Fh
    mov [RTCData+8],bl
    shr eax,4
    mov bl,al
    and bl,0Fh
    mov [RTCData+9],bl  ; month
    shr eax,8
    mov bl,al
    and bl,0Fh
    mov [RTCData+10],bl  ; year
    shr eax,4
    mov bl,al
    and bl,01Fh
    xor bh,bh
.notokay
    cmp bl,9
    jbe .okay
    inc bh
    sub bl,10
    jmp .notokay
.okay
    mov [RTCData+11],bl
    add bh,9
    mov [RTCData+12],bh
    shr eax,8
    and al,0Fh
    mov [RTCData+13],al ; day of week
.done
    pop eax
    pop ebx
.notfirst
    mov ebx,[RTCPtr]
    mov al,[RTCData+ebx]
    inc dword[RTCPtr]
    cmp dword[RTCPtr],0Fh
    jne .notclear
    mov dword[RTCPtr],0
.notclear
    pop ebx
    ret

RTC2801w:
;    mov byte[debstop3],1
    mov dword[RTCRest],0
    mov dword[RTCPtr],0
    cmp al,0Eh
    jne .notreset
    mov dword[RTCPtr2],0
    ret
.notreset
    cmp al,0Dh
    jne .notstop
    mov dword[RTCPtr2],0
    ret
.notstop
    push ebx
    mov ebx,[RTCPtr2]
    cmp ebx,0
    je .next
    cmp ebx,13
    ja .nomore
    mov [RTCData+ebx],al
.next
    inc dword[RTCPtr2]
.nomore
    pop ebx
    ret

NEWSYM RTCinit
    mov dword[RTCPtr],0
    ret
NEWSYM RTCReset
    setreg 2800h*4,RTC2800
    ret
NEWSYM RTCReset2
    setregw 2801h*4,RTC2801w
    ret

; SA-1 Start
; ----------

SECTION .data

; IRQ Stuff
NEWSYM SA1Mode, dd 0     ; 0 = SNES CPU, 1 = SA1 CPU
NEWSYM SA1Control, dd 0         ; don't execute if b5 or 6 are set
NEWSYM SA1BankPtr, dd 0
NEWSYM SA1ResetV, dd 0
NEWSYM SA1NMIV, dd 0
NEWSYM SA1IRQV, dd 0
NEWSYM SA1RV, dd 0
NEWSYM CurBWPtr, dd 0
NEWSYM SA1TempVar, dd 0
NEWSYM SA1IRQEn, dd 0
NEWSYM SA1Message, dd 0
NEWSYM SA1IRQExec, dd 0
NEWSYM SA1IRQEnable, dd 0
NEWSYM SA1DoIRQ, dd 0
; Arithmetic Stuff
NEWSYM SA1ARC, dd 0
NEWSYM SA1AR1, dd 0
NEWSYM SA1AR2, dd 0
NEWSYM SA1ARR1, dd 0
NEWSYM SA1ARR2,dd 0
NEWSYM SA1Stat, dd 0

NEWSYM SNSNMIV, dd 0
NEWSYM SNSIRQV, dd 0
NEWSYM SA1DMACount, dd 0
NEWSYM SA1DMAInfo, dd 0
NEWSYM SA1DMAChar, dd 0
NEWSYM SA1DMASource, dd 0
NEWSYM SA1DMADest, dd 0
NEWSYM SA1IRQTemp, dd 0

NEWSYM SA1BankSw, dd 1
NEWSYM SA1BankVal, db 0,1,2,3

NEWSYM BWShift, dd 0
NEWSYM BWAndAddr, dd 0
NEWSYM BWAnd, dd 0
NEWSYM BWRAnd, dd 0

SA1Reserved times 456 db 0


; SA1 Swap Stuff
NEWSYM SA1xa, dd 0
NEWSYM SA1xx, dd 0
NEWSYM SA1xy, dd 0
NEWSYM SA1xd, dd 0
NEWSYM SA1xdb, dd 0
NEWSYM SA1xpb, dd 0
NEWSYM SA1xs, dd 0
NEWSYM SA1RegP, dd 0
NEWSYM SA1RegE, dd 0
NEWSYM SA1RegPCS,dd 0
NEWSYM SA1BWPtr,dd 0
NEWSYM SA1Ptr, dd 0     ; Current PC, SA-1

NEWSYM SA1Overflow, dd 0
NEWSYM VarLenAddr, dd 0
NEWSYM VarLenAddrB, dd 0
NEWSYM VarLenBarrel, dd 0
NEWSYM SA1TimerVal, dd 0
NEWSYM SA1TimerSet, dd 0
NEWSYM SA1TimerCount, dd 0
NEWSYM SA1IRQData, dd 0

; SNES Swap Stuff
NEWSYM SNSRegP, dd 0
NEWSYM SNSRegE, dd 0
NEWSYM SNSRegPCS,dd 0
NEWSYM SNSBWPtr,dd 0
NEWSYM SNSPtr, dd 0     ; Current PC, SNES

NEWSYM IRAM, times 2049 db 0    ;2 kbytes of iram
num2writesa1reg equ $-SA1Mode
NEWSYM PHnum2writesa1reg, dd num2writesa1reg

NEWSYM SA1RAMArea, dd 0
NEWSYM SA1Temp, dd 0
NEWSYM Sdd1Mode, dd 0
NEWSYM Sdd1Bank, dd 0
NEWSYM Sdd1Addr, dd 0
NEWSYM Sdd1NewAddr, dd 0

SECTION .text

%macro SA1QuickF 2
NEWSYM %1
    mov [%2],al
    ret
%endmacro

NEWSYM SA1Reset
    mov byte[SA1IRQData+1],0
    mov byte[SA1Mode],0
    mov byte[SA1Status],0
    mov byte[SA1Control],20h
    mov dword[SA1DoIRQ],0
    mov ax,[irqv2]
    mov [irqv],ax
    mov ax,[nmiv2]
    mov [nmiv],ax
    mov eax,[romdata]
    sub eax,8000h
    mov [SA1RegPCS],eax
    mov eax,[romdata]
    add eax,4096*1024
    mov [SA1RAMArea],eax
    mov eax,[romdata]
    add eax,4096*1024-6000h
    mov [CurBWPtr],eax
    mov [SA1BWPtr],eax
    mov [SNSBWPtr],eax
    mov dword[SA1xa],0
    mov dword[SA1xx],0
    mov dword[SA1xy],0
    mov dword[SA1xd],0
    mov dword[SA1xdb],0
    mov dword[SA1xpb],0
    mov dword[SA1xs],1FFh
    mov dword[SA1RegP],0
    mov dword[SA1RegE],0
    mov dword[SA1IRQExec],0
    mov dword[SA1IRQEnable],0
    mov dword[SA1Message],0
    mov word[SA1Overflow],0
    ret

%macro BankSwitch 4
    push ecx
    push edx
    push eax
    mov [SA1BankVal+%1],al
    mov ebx,snesmmap+%2*4
    test al,80h
    jz .noupper
    cmp byte[NumofBanks],64
    jne .BSBigBank
    and eax,1
.BSBigBank
    and eax,07h
    shl eax,20
    push eax
    jmp .yesupper
.noupper
    cmp byte[NumofBanks],64
    jne .BSBigBank2
    and eax,1
.BSBigBank2
    and eax,07h
    shl eax,20
    push eax
    mov eax,%4
.yesupper
    mov ecx,20h
    add eax,[romdata]
    sub eax,8000h
.mmaploop
    mov [ebx],eax
    add eax,8000h
    add ebx,4
    dec ecx
    jnz .mmaploop
    pop eax
    add eax,[romdata]
    mov ecx,10h
    mov ebx,snesmap2+%3*4
    mov edx,snesmmap+%3*4
.mmaploop2
    mov [ebx],eax
    mov [edx],eax
    add eax,10000h
    add ebx,4
    add edx,4
    dec ecx
    jnz .mmaploop2
    pop eax
    pop edx
    pop ecx
    ret
%endmacro

NEWSYM sa12220w
    BankSwitch 0,0,0C0h,0
NEWSYM sa12221w
    BankSwitch 1,20h,0D0h,100000h
NEWSYM sa12222w
    BankSwitch 2,80h,0E0h,200000h
NEWSYM sa12223w
    BankSwitch 3,0A0h,0F0h,300000h

%macro BankSwitchSDD1 2
    push ecx
    push edx
    push eax
    mov [SDD1BankA+%1],al
    and eax,07h
    shl eax,20
    add eax,[romdata]
    mov ecx,10h
    mov ebx,snesmap2+%2*4
    mov edx,snesmmap+%2*4
.mmaploop2
    mov [ebx],eax
    mov [edx],eax
    add eax,10000h
    add ebx,4
    add edx,4
    dec ecx
    jnz .mmaploop2
    pop eax
    pop edx
    pop ecx
    ret
%endmacro

sdd14804:
    mov al,[SDD1BankA]
    ret
sdd14805:
    mov al,[SDD1BankA+1]
    ret
sdd14806:
    mov al,[SDD1BankA+2]
    ret
sdd14807:
    mov al,[SDD1BankA+3]
    ret

NEWSYM sdd14804w
    BankSwitchSDD1 0,0C0h
NEWSYM sdd14805w
    BankSwitchSDD1 1,0D0h
NEWSYM sdd14806w
    BankSwitchSDD1 2,0E0h
NEWSYM sdd14807w
    BankSwitchSDD1 3,0F0h

NEWSYM sa12200w
    mov bl,al
    and bl,0Fh
    mov [SA1Message],bl
    test al,80h
    jz .noirq
    or byte[SA1DoIRQ],1
.noirq
    test al,10h
    jz .nonmi
    or byte[SA1DoIRQ],2
.nonmi
    test byte[SA1Control],20h
    jz .noreset
    test al,20h
    jnz .noreset
    mov [SA1Control],al
    mov ebx,[romdata]
    mov [SA1BankPtr],ebx
    xor ebx,ebx
    mov bx,[SA1ResetV]
    add ebx,[romdata]
    sub ebx,8000h
    mov [SA1Ptr],ebx
    mov byte[SA1xpb],0
    mov word[SA1xs],1FFh
    mov ebx,[romdata]
    sub ebx,8000h
    mov [SA1RegPCS],ebx
    xor ebx,ebx
    ret
.noreset
    mov [SA1Control],al
    ret

NEWSYM sa12201w         ; IRQ Enable
    mov [SA1IRQEnable],al
    ret
NEWSYM sa12202w         ; IRQ Clear
    test al,80h
    jz .noirqclear
    and byte[SA1IRQExec],0FEh
    and byte[SA1DoIRQ],0FBh
.noirqclear
    test al,20h
    jz .nocdmairqclear
    and byte[SA1IRQExec],0FDh
    and byte[SA1DoIRQ],0F7h
.nocdmairqclear
    ret

SA1QuickF sa12203w, SA1ResetV
SA1QuickF sa12204w, SA1ResetV+1
SA1QuickF sa12205w, SA1NMIV
SA1QuickF sa12206w, SA1NMIV+1
SA1QuickF sa12207w, SA1IRQV
SA1QuickF sa12208w, SA1IRQV+1
NEWSYM sa12209w ; IRQ Stuff
    mov [SA1IRQData+1],al
    test al,80h
    jz .noirq
    ; execute IRQ on the SNES
    or byte[SA1DoIRQ],4
.noirq
    mov bl,al
    and bl,0Fh
    mov [SA1Message+1],bl
    mov bx,[irqv2]
    test al,40h
    jz .noirqchange
    mov bx,[SNSIRQV]
.noirqchange
    mov [irqv],bx
    mov bx,[nmiv2]
    test al,10h
    jz .nonmichange
    mov bx,[SNSNMIV]
.nonmichange
    mov [nmiv],bx
    ret

SA1QuickF sa1220Aw, SA1IRQEn

NEWSYM sa1220Bw         ; SA-1 IRQ Clear
    test al,80h
    jz .noirqclear
    mov byte[SA1IRQExec+1],0
    and byte[SA1DoIRQ],0FEh
.noirqclear
    test al,20h
    jz .nocdmairqclear
.nocdmairqclear
    test al,10h
    jz .nonmiclear
    mov byte[SA1IRQExec+2],0
    and byte[SA1DoIRQ],0FDh
.nonmiclear
    ret

SA1QuickF sa1220Cw, SNSNMIV
SA1QuickF sa1220Dw, SNSNMIV+1
SA1QuickF sa1220Ew, SNSIRQV
SA1QuickF sa1220Fw, SNSIRQV+1

NEWSYM sa12224w ; BWRAM
    mov bl,al
    and ebx,1Fh
    shl ebx,13
    add ebx,[romdata]
    add ebx,1024*4096-6000h
    mov [SNSBWPtr],ebx
    cmp byte[SA1Status],0
    jne .nosnes
    mov [CurBWPtr],ebx
.nosnes
    ret
NEWSYM sa12225w ; BWRAM
    mov [BWUsed2],al
    test al,80h
    jnz .upper
    mov bl,al
    and ebx,1Fh
    shl ebx,13
    add ebx,[romdata]
    add ebx,1024*4096-6000h
    mov [SA1BWPtr],ebx
    cmp byte[SA1Status],0
    je .nosa1b
    mov [CurBWPtr],ebx
.nosa1b
    mov byte[BWShift],0
    mov byte[BWAndAddr],0
    mov byte[BWAnd],0FFh
    mov byte[BWRAnd],0h
    ret
.upper
    mov bl,al
    and ebx,7Fh
    test byte[SA1Overflow+1],80h
    jz .16col
    shl ebx,11
    mov byte[BWShift],2
    mov byte[BWAndAddr],03h
    mov byte[BWAnd],03h
    mov byte[BWRAnd],0FCh
    jmp .4col
.16col
    mov byte[BWShift],1
    mov byte[BWAndAddr],01h
    mov byte[BWAnd],0Fh
    mov byte[BWRAnd],0F0h
    and ebx,3Fh
    shl ebx,12
.4col
    add ebx,[romdata]
    add ebx,1024*4096
    mov [SA1BWPtr],ebx
    cmp byte[SA1Status],0
    je .nosa1
    mov [CurBWPtr],ebx
.nosa1
;    mov byte[debstop3],1
    ret
NEWSYM sa12250w
    mov [SA1ARC],al
    mov byte[SA1ARC+1],1
    test al,2
    jz .notcumul
    mov word[SA1ARR1],0
    mov word[SA1ARR1+2],0
    mov word[SA1ARR1+4],0
.notcumul
    ret
NEWSYM sa12251w
    mov [SA1AR1],al
    mov byte[SA1ARC+1],1
    ret
NEWSYM sa12252w
    mov [SA1AR1+1],al
    mov byte[SA1ARC+1],1
    ret
NEWSYM sa12253w
    mov [SA1AR2],al
    mov byte[SA1ARC+1],1
    ret
NEWSYM sa12254w
    mov [SA1AR2+1],al
    mov byte[SA1ARC+1],1
    test byte[SA1ARC],2
    jnz .cumul
    call UpdateArithStuff
    ret
    ; set overflow bit if exceeds 40bits
.cumul
    pushad
    xor edx,edx
    mov ax,[SA1AR1]
    mov bx,[SA1AR2]
    imul bx
    shl edx,16
    mov dx,ax
    mov byte[SA1Overflow],0
    add [SA1ARR1],edx
    adc byte[SA1ARR2],0
    jnc .notoverflow
    mov byte[SA1Overflow],80h
.notoverflow
    popad
    ret

UpdateArithStuff:
    cmp byte[SA1ARC+1],1
    jne .noarith
    pushad
    mov byte[SA1ARC+1],0
    test byte[SA1ARC],3
    jz .multiply
    test byte[SA1ARC],2
    jnz near .cumulativesum
    test byte[SA1ARC],1
    jnz .division
.multiply
    xor edx,edx
    mov ax,[SA1AR1]
    mov bx,[SA1AR2]
    imul bx
    mov [SA1ARR1],ax
    mov [SA1ARR1+2],dx
    popad
.noarith
    ret
.division
    movsx eax,word[SA1AR1]
    xor edx,edx
    test eax,80000000h
    jz .notneg
    mov edx,0FFFFFFFFh
.notneg
    xor ebx,ebx
    mov bx,[SA1AR2]
    or ebx,ebx
    jz .invalid
    idiv ebx
    mov [SA1ARR1],ax
    mov [SA1ARR1+2],dx
;    mov word[SA1AR1],0
;    mov word[SA1AR2],0
    popad
    ret
.invalid
    mov word[SA1ARR1],0
    mov word[SA1ARR1+2],0