regsw.inc

十七种模拟器源代码 非常有用的作课程设计不可缺少的

    mov bl,al
    shr bl,2
    shl bx,11
    mov [bg1ptr],bx
    mov [bg1ptrb],bx
    mov [bg1ptrc],bx
    mov [bg1ptrd],bx
    mov dword[bg1ptrx],0
    mov dword[bg1ptry],0
    mov bl,al
    and bl,00000011b
    mov [bg1scsize],bl
    cmp bl,1
    jne .skipa
    add word[bg1ptrb],800h
    add word[bg1ptrd],800h
    mov dword[bg1ptrx],800h
.skipa
    cmp bl,2
    jne .skipb
    add word[bg1ptrc],800h
    add word[bg1ptrd],800h
    mov dword[bg1ptry],800h
.skipb
    cmp bl,3
    jne .skipc
    add word[bg1ptrb],800h
    add word[bg1ptrc],1000h
    add word[bg1ptrd],1800h
    mov dword[bg1ptrx],800h
    mov dword[bg1ptry],1000h
.skipc
    ret

; BG2 VRAM location register
reg2108w:
    xor ebx,ebx
    mov bl,al
    shr bl,2
    shl bx,11
    mov [bg2ptr],bx
    mov [bg2ptrb],bx
    mov [bg2ptrc],bx
    mov [bg2ptrd],bx
    mov dword[bg2ptrx],0
    mov dword[bg2ptry],0
    mov bl,al
    and bl,00000011b
    mov [bg2scsize],bl
    cmp bl,1
    jne .skipa
    add word[bg2ptrb],800h
    add word[bg2ptrd],800h
    mov dword[bg2ptrx],800h
.skipa
    cmp bl,2
    jne .skipb
    add word[bg2ptrc],800h
    add word[bg2ptrd],800h
    mov dword[bg2ptry],800h
.skipb
    cmp bl,3
    jne .skipc
    add word[bg2ptrb],800h
    add word[bg2ptrc],1000h
    add word[bg2ptrd],1800h
    mov dword[bg2ptrx],800h
    mov dword[bg2ptry],1000h
.skipc                  
    ret

; BG3 VRAM location register
reg2109w:
    xor ebx,ebx
    mov bl,al
    shr bl,2
    shl bx,11
    mov [bg3ptr],bx
    mov [bg3ptrb],bx
    mov [bg3ptrc],bx
    mov [bg3ptrd],bx
    mov dword[bg3ptrx],0
    mov dword[bg3ptry],0
    mov bl,al
    and bl,00000011b
    mov [bg3scsize],bl
    cmp bl,1
    jne .skipa
    add word[bg3ptrb],800h
    add word[bg3ptrd],800h
    mov dword[bg3ptrx],800h
.skipa
    cmp bl,2
    jne .skipb
    add word[bg3ptrc],800h
    add word[bg3ptrd],800h
    mov dword[bg3ptry],800h
.skipb
    cmp bl,3
    jne .skipc
    add word[bg3ptrb],800h
    add word[bg3ptrc],1000h
    add word[bg3ptrd],1800h
    mov dword[bg3ptrx],800h
    mov dword[bg3ptry],1000h
.skipc
    ret

; BG4 VRAM location register
reg210Aw:
    xor ebx,ebx
    mov bl,al
    shr bl,2
    shl bx,11
    mov [bg4ptr],bx
    mov [bg4ptrb],bx
    mov [bg4ptrc],bx
    mov [bg4ptrd],bx
    mov dword[bg4ptrx],0
    mov dword[bg4ptry],0
    mov bl,al
    and bl,00000011b
    mov [bg4scsize],bl
    cmp bl,1
    jne .skipa
    add word[bg4ptrb],800h
    add word[bg4ptrd],800h
    mov dword[bg4ptrx],800h
.skipa
    cmp bl,2
    jne .skipb
    add word[bg4ptrc],800h
    add word[bg4ptrd],800h
    mov dword[bg4ptry],800h
.skipb
    cmp bl,3
    jne .skipc
    add word[bg4ptrb],800h
    add word[bg4ptrc],1000h
    add word[bg4ptrd],1800h
    mov dword[bg4ptrx],800h
    mov dword[bg4ptry],1000h
.skipc
    ret

; BG1 & BG2 VRAM location register
reg210Bw:
    xor ebx,ebx
    mov bl,al
    and bl,0Fh
    shl bx,13
    mov [bg1objptr],bx
    mov bl,al
    shr bl,4
    shl bx,13
    mov [bg2objptr],bx
    ret

; BG3 & BG4 VRAM location register
reg210Cw:
    xor ebx,ebx
    mov bl,al
    and bl,0Fh
    shl bx,13
    mov [bg3objptr],bx
    mov bl,al
    shr bl,4
    shl bx,13
    mov [bg4objptr],bx
    ret

; BG1 horizontal scroll register
reg210Dw:
    mov bl,byte[bg1scrolx+1]
    mov byte[bg1scrolx],bl
    mov byte[bg1scrolx+1],al
    ret

; BG1 vertical scroll register
reg210Ew:
    mov bl,byte[bg1scroly+1]
    add bl,[bgscroltemp]
    mov byte[bg1scroly],bl
    mov byte[bg1scroly+1],al
    ret

bgscroltemp db 0

; BG2 horizontal scroll register
reg210Fw:
    mov bl,byte[bg2scrolx+1]
    mov byte[bg2scrolx],bl
    mov byte[bg2scrolx+1],al
    ret

; BG2 vertical scroll register
reg2110w:
    mov bl,byte[bg2scroly+1]
    add bl,[bgscroltemp]
    mov byte[bg2scroly],bl
    mov byte[bg2scroly+1],al
    ret

; BG3 horizontal scroll register
reg2111w:
    mov bl,byte[bg3scrolx+1]
    mov byte[bg3scrolx],bl
    mov byte[bg3scrolx+1],al
    ret

; BG3 vertical scroll register
reg2112w:
    mov bl,byte[bg3scroly+1]
    add bl,[bgscroltemp]
    mov byte[bg3scroly],bl
    mov byte[bg3scroly+1],al
    ret

; BG4 horizontal scroll register
reg2113w:
    mov bl,byte[bg4scrolx+1]
    mov byte[bg4scrolx],bl
    mov byte[bg4scrolx+1],al
    ret

; BG4 vertical scroll register
reg2114w:
    mov bl,byte[bg4scroly+1]
    add bl,[bgscroltemp]
    mov byte[bg4scroly],bl
    mov byte[bg4scroly+1],al
    ret

; Video port control
reg2115w:
    and al,11111111b
    mov [vraminctype],al
    mov bl,al
    and bl,00000011b
    cmp bl,0
    jne .skip1
    mov word[addrincr],2
.skip1
    cmp bl,1
    jne .skip2
    mov word[addrincr],64
.skip2
    cmp bl,2
    jne .skip3
    mov word[addrincr],256
.skip3
    cmp bl,3
    jne .skip4
    mov word[addrincr],256
.skip4
    mov bl,al
    mov byte[vramincby8on],0
    and bl,00001100b
    jz near .noincby8
    mov byte[vramincby8on],1
    cmp bl,4
    jne .nextinc8
    mov byte[vramincby8left],64-1
    mov byte[vramincby8totl],5
    mov word[vramincby8ptri],65535-511
    mov word[vramincby8var],256+128+64
.nextinc8
    cmp bl,8
    jne .nextinc8b
    mov byte[vramincby8left],128-1
    mov byte[vramincby8totl],6
    mov word[vramincby8ptri],65535-1023
    mov word[vramincby8var],512+256+128
.nextinc8b
    cmp bl,12
    jne .nextinc8c
    mov byte[vramincby8left],256-1
    mov byte[vramincby8totl],7
    mov word[vramincby8ptri],65535-2047
    mov word[vramincby8var],1024+512+256
.nextinc8c
    mov ebx,[regptw]
    test al,80h
    jz .from2118
    mov dword[ebx+2118h*4],reg2118inc8
    mov dword[ebx+2119h*4],reg2119inc8inc
    mov byte[vramincr],0
    jmp .from2119
.from2118
    mov dword[ebx+2118h*4],reg2118inc8inc
    mov dword[ebx+2119h*4],reg2119inc8
    mov byte[vramincr],1
.from2119
    ret
.noincby8
    mov ebx,[regptw]
    test al,80h
    jz .from2118b
    mov dword[ebx+2118h*4],reg2118
    mov dword[ebx+2119h*4],reg2119inc
    mov byte[vramincr],0
    jmp .from2119b
.from2118b
    mov dword[ebx+2118h*4],reg2118inc
    mov dword[ebx+2119h*4],reg2119
    mov byte[vramincr],1
.from2119b
    ret

; Video port address (Low)
reg2116w:
    shr word[vramaddr],1
    mov byte[vramaddr],al
    shl word[vramaddr],1
    mov byte[vramread],0
    ret

; Video port address (High)
reg2117w:
    shr word[vramaddr],1
    mov byte[vramaddr+1],al
    shl word[vramaddr],1
    mov byte[vramread],0

    xor ebx,ebx
    mov bx,[vramaddr]
    add ebx,[vram]
    mov bl,[ebx]
    mov [vramread],bl
    xor ebx,ebx
    mov bx,[vramaddr]
    add ebx,[vram]
    mov bl,[ebx+1]
    mov [vramread2],bl
    ret

; Video port data (Low)
reg2118:
    mov ebx,[vramaddr]
    mov [vrama+ebx],al
    shr ebx,4
    mov byte[vidmemch2+ebx],1
    mov byte[vidmemch4+ebx],1
    mov byte[vidmemch8+ebx],1
    ret

reg2118inc:
    mov ebx,[vramaddr]
    mov [vrama+ebx],al
    shr ebx,4
    mov byte[vidmemch2+ebx],1
    mov byte[vidmemch4+ebx],1
    mov byte[vidmemch8+ebx],1
    mov ebx,[addrincr]
    add [vramaddr],bx
    ret

reg2118inc8:
    push ecx
    xor ecx,ecx
    mov ebx,[vramaddr]
    mov cl,[vramincby8left]
    and ebx,ecx
    shl ebx,3
    push eax
    mov eax,[vramaddr]
    and ax,[vramincby8var]
    mov cl,[vramincby8totl]
    shr eax,cl
    add ebx,eax
    mov eax,[vramaddr]
    and ax,[vramincby8ptri]
    add ebx,eax
    pop eax
    pop ecx
    add ebx,[vram]
;    cmp [ebx],al
;    je .nochange2
    mov [ebx],al
    sub ebx,[vram]
    shr ebx,4
    mov byte[vidmemch2+ebx],1
    mov byte[vidmemch4+ebx],1
    mov byte[vidmemch8+ebx],1
.nochange2
    ret

reg2118inc8inc:
    push ecx
    xor ecx,ecx
    mov ebx,[vramaddr]
    mov cl,[vramincby8left]
    and ebx,ecx
    shl ebx,3
    push eax
    mov eax,[vramaddr]
    and ax,[vramincby8var]
    mov cl,[vramincby8totl]
    shr eax,cl
    add ebx,eax
    mov eax,[vramaddr]
    and ax,[vramincby8ptri]
    add ebx,eax
    pop eax
    pop ecx
    add ebx,[vram]
;    cmp [ebx],al
;    je .nochange2
    mov [ebx],al
    sub ebx,[vram]
    shr ebx,4
    mov byte[vidmemch2+ebx],1
    mov byte[vidmemch4+ebx],1
    mov byte[vidmemch8+ebx],1
.nochange2
    mov ebx,[addrincr]
    add [vramaddr],bx
    ret

reg2119:
    cmp dword[vramaddr],0E000h
    jb .skip
    mov byte[debstop],1
.skip
    mov ebx,[vramaddr]
;    cmp [vrama+ebx+1],al
;    je .nochange
    mov [vrama+ebx+1],al
    shr ebx,4
    mov byte[vidmemch2+ebx],1
    mov byte[vidmemch4+ebx],1
    mov byte[vidmemch8+ebx],1
.nochange
    ret

reg2119inc:
    mov ebx,[vramaddr]
;    cmp [vrama+ebx+1],al
;    je .nochange
    mov [vrama+ebx+1],al
    shr ebx,4
    mov byte[vidmemch2+ebx],1
    mov byte[vidmemch4+ebx],1
    mov byte[vidmemch8+ebx],1
.nochange
    mov ebx,[addrincr]
    add [vramaddr],bx
    ret

reg2119inc8:
    push ecx
    xor ecx,ecx
    mov ebx,[vramaddr]
    mov cl,[vramincby8left]
    and ebx,ecx
    shl ebx,3
    push eax
    mov eax,[vramaddr]
    and ax,[vramincby8var]
    mov cl,[vramincby8totl]
    shr eax,cl
    add ebx,eax
    mov eax,[vramaddr]
    and ax,[vramincby8ptri]
    add ebx,eax
    pop eax
    pop ecx
;    cmp [vrama+ebx+1],al
;    je .nochange2
    mov [vrama+ebx+1],al
    shr ebx,4
    mov byte[vidmemch2+ebx],1
    mov byte[vidmemch4+ebx],1
    mov byte[vidmemch8+ebx],1
.nochange2
    ret

reg2119inc8inc:
    push ecx
    xor ecx,ecx
    mov ebx,[vramaddr]
    mov cl,[vramincby8left]
    and ebx,ecx
    shl ebx,3
    push eax
    mov eax,[vramaddr]
    and ax,[vramincby8var]
    mov cl,[vramincby8totl]
    shr eax,cl
    add ebx,eax
    mov eax,[vramaddr]
    and ax,[vramincby8ptri]
    add ebx,eax
    pop eax
    pop ecx
;    cmp [vrama+ebx+1],al
;    je .nochange2
    mov [vrama+ebx+1],al
    shr ebx,4
    mov byte[vidmemch2+ebx],1
    mov byte[vidmemch4+ebx],1
    mov byte[vidmemch8+ebx],1
.nochange2
    mov ebx,[addrincr]
    add [vramaddr],bx
    ret

; MODE7 settings register
reg211Aw:
    mov [mode7set],al
    ret

NEWSYM multchange, db 1

; COS (COSINE) rotate angle / X Expansion
reg211Bw:
    mov bl,[mode7A+1]
    mov [mode7A],bl
    mov [mode7A+1],al
    mov byte[multchange],1
    ret

; SIN (SIN)    rotate angle / X Expansion & Complement Multiplication Start
reg211Cw:
    mov bl,[mode7B+1]
    mov [mode7B],bl
    mov [mode7B+1],al
    mov byte[multchange],1
    ret

; SIN (SIN)    rotate angle / Y Expansion
reg211Dw:
    mov bl,[mode7C+1]
    mov [mode7C],bl
    mov [mode7C+1],al
    ret

; COS (COSINE) rotate angle / Y Expansion
reg211Ew:
    mov bl,[mode7D+1]
    mov [mode7D],bl
    mov [mode7D+1],al
    ret

; Center position X (13-bit data only)
reg211Fw:
    mov bl,[mode7X0+1]
    mov [mode7X0],bl
    mov [mode7X0+1],al
    ret

; Center position Y (13-bit data only)
reg2120w:
    mov bl,[mode7Y0+1]
    mov [mode7Y0],bl
    mov [mode7Y0+1],al
    ret

; Colour # (or palette) selection register
reg2121w:
    xor bh,bh
    mov bl,al
    shl bx,1
    mov [cgaddr],bx
    and word[cgaddr],01FFh
    ret

; Colour data register
reg2122w:
    xor ebx,ebx
    mov bx,[cgaddr]
    cmp [cgram+ebx],al
    je .nomod
    mov [cgram+ebx],al
    mov byte[cgmod],1
.nomod
    inc word[cgaddr]
    and word[cgaddr],01FFh
    ret

; Window mask settings register [W12SEL]
reg2123w:
    mov bl,al
    and bl,0Fh
    test bl,0Ah
    jnz .nen1
;    or bl,02h
.nen1
    mov [winbg1en],bl
    mov bl,al
    shr bl,4
    test bl,0Ah
    jnz .nen2
;    or bl,02h
.nen2
    mov [winbg2en],bl
    ret

; Window mask settings register [W34SEL]
reg2124w:
    mov bl,al
    and bl,0Fh
    test bl,0Ah