Software Vault: The Games Collection 1

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Assembly Source File | 1993-08-20 | 49KB | 2,513 lines

; 640x480x256 (requires register-compatible VGA+) ; Loadable driver for The Graphics Engine ; Copyright (c) 1993 by Matthew Hildebrand ; Turbo Assembler syntax ; Portions by John Bridges IDEAL P486N ; 386 code, but we want 486 alignment MODEL LARGE SCREEN_WIDE = 640 SCREEN_DEEP = 480 NUM_COLOURS = 256 CODESEG ORG 0 ;*** Signature db 'TGE3' ;*** Non-I/O functions _initGraphics dw initGraphics ; initGraphics dw ? _deInitGraphics dw 0 ; deInitGraphics dw ? _setPaletteReg dw setPaletteReg ; setPaletteReg dw ? _getPaletteReg dw getPaletteReg ; getPaletteReg dw ? _setBlockPalette dw setBlockPalette ; setBlockPalette dw ? _getBlockPalette dw getBlockPalette ; getBlockPalette dw ? _colourCloseTo dw 0 ; colourCloseTo dw ? _colourCloseToX dw 0 ; colourCloseToX dw ? _imageSize dw 0 ; imageSize dw ? _imageSizeDim dw 0 ; imageSizeDim dw ? _setPage dw 0 ; setPage (not implemented yet) dw ? ;*** Currently active I/O functions (filled in by loadGraphDriver()) dd 20 DUP(?) ;*** Input functions _getImage_scr dw 0 ; getImage dw ? _getImage_mem dw 0 dw ? _getLine_scr dw getLine_scr ; getLine dw ? _getLine_mem dw getLine_mem dw ? _getPixel_scr dw getPixel_scr ; getPixel dw ? _getPixel_mem dw getPixel_mem dw ? ;*** Output functions _putImage_scr_copy dw 0 ; putImage dw ? _putImage_scr_and dw 0 dw ? _putImage_scr_not dw 0 dw ? _putImage_scr_or dw 0 dw ? _putImage_scr_xor dw 0 dw ? _putImage_mem_copy dw 0 dw ? _putImage_mem_and dw 0 dw ? _putImage_mem_not dw 0 dw ? _putImage_mem_or dw 0 dw ? _putImage_mem_xor dw 0 dw ? _putImageInv_scr_copy dw 0 ; putImageInv dw ? _putImageInv_scr_and dw 0 dw ? _putImageInv_scr_not dw 0 dw ? _putImageInv_scr_or dw 0 dw ? _putImageInv_scr_xor dw 0 dw ? _putImageInv_mem_copy dw 0 dw ? _putImageInv_mem_and dw 0 dw ? _putImageInv_mem_not dw 0 dw ? _putImageInv_mem_or dw 0 dw ? _putImageInv_mem_xor dw 0 dw ? _putLine_scr_copy dw putLine_scr_copy ; putLine dw ? _putLine_scr_and dw 0 dw ? _putLine_scr_not dw 0 dw ? _putLine_scr_or dw 0 dw ? _putLine_scr_xor dw 0 dw ? _putLine_mem_copy dw putLine_mem_copy dw ? _putLine_mem_and dw 0 dw ? _putLine_mem_not dw 0 dw ? _putLine_mem_or dw 0 dw ? _putLine_mem_xor dw 0 dw ? _putLineInv_scr_copy dw 0 ; putLineInv dw ? _putLineInv_scr_and dw 0 dw ? _putLineInv_scr_not dw 0 dw ? _putLineInv_scr_or dw 0 dw ? _putLineInv_scr_xor dw 0 dw ? _putLineInv_mem_copy dw 0 dw ? _putLineInv_mem_and dw 0 dw ? _putLineInv_mem_not dw 0 dw ? _putLineInv_mem_or dw 0 dw ? _putLineInv_mem_xor dw 0 dw ? _putPixel_scr_copy dw putPixel_scr_copy ; putPixel dw ? _putPixel_scr_and dw 0 dw ? _putPixel_scr_not dw 0 dw ? _putPixel_scr_or dw 0 dw ? _putPixel_scr_xor dw 0 dw ? _putPixel_mem_copy dw putPixel_mem_copy dw ? _putPixel_mem_and dw putPixel_mem_and dw ? _putPixel_mem_not dw putPixel_mem_not dw ? _putPixel_mem_or dw putPixel_mem_or dw ? _putPixel_mem_xor dw putPixel_mem_xor dw ? _line_scr_copy dw 0 ; line dw ? _line_scr_and dw 0 dw ? _line_scr_not dw 0 dw ? _line_scr_or dw 0 dw ? _line_scr_xor dw 0 dw ? _line_mem_copy dw 0 dw ? _line_mem_and dw 0 dw ? _line_mem_not dw 0 dw ? _line_mem_or dw 0 dw ? _line_mem_xor dw 0 dw ? _horizLine_scr_copy dw horizLine_scr_copy ; horizLine dw ? _horizLine_scr_and dw 0 dw ? _horizLine_scr_not dw 0 dw ? _horizLine_scr_or dw 0 dw ? _horizLine_scr_xor dw 0 dw ? _horizLine_mem_copy dw horizLine_mem_copy dw ? _horizLine_mem_and dw 0 dw ? _horizLine_mem_not dw 0 dw ? _horizLine_mem_or dw 0 dw ? _horizLine_mem_xor dw 0 dw ? _vertLine_scr_copy dw 0 ; vertLine dw ? _vertLine_scr_and dw 0 dw ? _vertLine_scr_not dw 0 dw ? _vertLine_scr_or dw 0 dw ? _vertLine_scr_xor dw 0 dw ? _vertLine_mem_copy dw 0 dw ? _vertLine_mem_and dw 0 dw ? _vertLine_mem_not dw 0 dw ? _vertLine_mem_or dw 0 dw ? _vertLine_mem_xor dw 0 dw ? _drawRect_scr_copy dw 0 ; drawRect dw ? _drawRect_scr_and dw 0 dw ? _drawRect_scr_not dw 0 dw ? _drawRect_scr_or dw 0 dw ? _drawRect_scr_xor dw 0 dw ? _drawRect_mem_copy dw 0 dw ? _drawRect_mem_and dw 0 dw ? _drawRect_mem_not dw 0 dw ? _drawRect_mem_or dw 0 dw ? _drawRect_mem_xor dw 0 dw ? _filledRect_scr_copy dw 0 ; filledRect dw ? _filledRect_scr_and dw 0 dw ? _filledRect_scr_not dw 0 dw ? _filledRect_scr_or dw 0 dw ? _filledRect_scr_xor dw 0 dw ? _filledRect_mem_copy dw 0 dw ? _filledRect_mem_and dw 0 dw ? _filledRect_mem_not dw 0 dw ? _filledRect_mem_or dw 0 dw ? _filledRect_mem_xor dw 0 dw ? _clearGraphics_scr_copy dw 0 ; clearGraphics dw ? _clearGraphics_scr_and dw 0 dw ? _clearGraphics_scr_not dw 0 dw ? _clearGraphics_scr_or dw 0 dw ? _clearGraphics_scr_xor dw 0 dw ? _clearGraphics_mem_copy dw 0 dw ? _clearGraphics_mem_and dw 0 dw ? _clearGraphics_mem_not dw 0 dw ? _clearGraphics_mem_or dw 0 dw ? _clearGraphics_mem_xor dw 0 dw ? _ellipse_scr_copy dw 0 ; ellipse dw ? _ellipse_scr_and dw 0 dw ? _ellipse_scr_not dw 0 dw ? _ellipse_scr_or dw 0 dw ? _ellipse_scr_xor dw 0 dw ? _ellipse_mem_copy dw 0 dw ? _ellipse_mem_and dw 0 dw ? _ellipse_mem_not dw 0 dw ? _ellipse_mem_or dw 0 dw ? _ellipse_mem_xor dw 0 dw ? _filledEllipse_scr_copy dw 0 ; filledEllipse dw ? _filledEllipse_scr_and dw 0 dw ? _filledEllipse_scr_not dw 0 dw ? _filledEllipse_scr_or dw 0 dw ? _filledEllipse_scr_xor dw 0 dw ? _filledEllipse_mem_copy dw 0 dw ? _filledEllipse_mem_and dw 0 dw ? _filledEllipse_mem_not dw 0 dw ? _filledEllipse_mem_or dw 0 dw ? _filledEllipse_mem_xor dw 0 dw ? _circle_scr_copy dw 0 ; circle dw ? _circle_scr_and dw 0 dw ? _circle_scr_not dw 0 dw ? _circle_scr_or dw 0 dw ? _circle_scr_xor dw 0 dw ? _circle_mem_copy dw 0 dw ? _circle_mem_and dw 0 dw ? _circle_mem_not dw 0 dw ? _circle_mem_or dw 0 dw ? _circle_mem_xor dw 0 dw ? _filledCircle_scr_copy dw 0 ; filledCircle dw ? _filledCircle_scr_and dw 0 dw ? _filledCircle_scr_not dw 0 dw ? _filledCircle_scr_or dw 0 dw ? _filledCircle_scr_xor dw 0 dw ? _filledCircle_mem_copy dw 0 dw ? _filledCircle_mem_and dw 0 dw ? _filledCircle_mem_not dw 0 dw ? _filledCircle_mem_or dw 0 dw ? _filledCircle_mem_xor dw 0 dw ? _fillRegion_scr_copy dw 0 ; fillRegion dw ? _fillRegion_scr_and dw 0 dw ? _fillRegion_scr_not dw 0 dw ? _fillRegion_scr_or dw 0 dw ? _fillRegion_scr_xor dw 0 dw ? _fillRegion_mem_copy dw 0 dw ? _fillRegion_mem_and dw 0 dw ? _fillRegion_mem_not dw 0 dw ? _fillRegion_mem_or dw 0 dw ? _fillRegion_mem_xor dw 0 dw ? _fillLine_scr_copy dw horizLine_scr_copy ; fillLine dw ? _fillLine_scr_and dw 0 dw ? _fillLine_scr_not dw 0 dw ? _fillLine_scr_or dw 0 dw ? _fillLine_scr_xor dw 0 dw ? _fillLine_mem_copy dw horizLine_mem_copy dw ? _fillLine_mem_and dw 0 dw ? _fillLine_mem_not dw 0 dw ? _fillLine_mem_or dw 0 dw ? _fillLine_mem_xor dw 0 dw ? ;*** Mode information scrnMaxX dw 639 ; physical dimensions scrnMaxY dw 479 maxColour dw 255 ; maximum colour number xRatio dw 4 ; aspect ratio 4:3 (640:480 in yRatio dw 3 ; lowest terms) bitsPerPixel dw 8 ; 8 bits per pixel inMaxX dw 639 ; current input screen dimensions inMaxY dw 479 outMaxX dw 639 ; current output screen dimensions outMaxY dw 479 inScreenWide dw ? ; needed only for virtual screens outScreenWide dw ? ;*** Viewport information inViewportULX dw 0 inViewportULY dw 0 inViewportLRX dw 639 inViewportLRY dw 479 outViewportULX dw 0 outViewportULY dw 0 outViewportLRX dw 639 outViewportLRY dw 479 ;*** Paging information pagingSupported dw ? ; not implemented yet curPage dw ? ; not implemented yet maxPage dw ? ; not implemented yet ;*** Force (image width MOD imageWideAdjust) = 0. imageWideAdjust dw ? ; not implemented yet ;*** Current and screen addresses LABEL inAddr DWORD ; current input address inOff dw 0 inSeg dw 0A000h LABEL outAddr DWORD ; current output address outOff dw 0 outSeg dw 0A000h LABEL scrAddr DWORD ; screen address scrOff dw 0 scrSeg dw 0A000h ;*** Copyright string db 'The Graphics Engine -- Copyright (c) 1993 by Matthew Hildebrand' inited db 0 colourPalette db 768 DUP(?) lineOffs dw SCREEN_DEEP DUP(?) bankNum dw SCREEN_DEEP DUP(?) bankChanges dw SCREEN_DEEP DUP(?) curBank dw ? screenWide dw ? bankadr dw OFFSET _nobank vgamem dw ? bksize dw ? bksizeShl10Dec dw ? retval dw ? ; first return value from whichVGA() scanline dw ? acumos dw ? aheada dw ? aheadb dw ? ativga dw ? chipstech dw ? cirrus dw ? compaq dw ? everex dw ? genoa dw ? ncr dw ? oak067 dw ? paradise dw ? trident dw ? t8900 dw ? tseng dw ? tseng4 dw ? video7 dw ? vesa dw ? ; VESA information STRUC vgainfo VESASignature db 4 dup (?) ; 4 signature bytes VESAVersion dw ? ; VESA version number OEMStringPtr dd ? ; Pointer to OEM string Capabilities db 4 dup (?) ; Capabilities of the video environment VideoModePtr dd ? ; Pointer to supported Super VGA modes ENDS STRUC vesamode ModeAttributes dw ? ; mode attributes WinAAttributes db ? ; window A attributes WinBAttributes db ? ; window B attributes WinGranularity dw ? ; window granularity WinSize dw ? ; window size WinASegment dw ? ; window A start segment WinBSegment dw ? ; window B start segment WinFuncPtr dd ? ; pointer to window function BytesPerLine dw ? ; bytes per scan line ; optional information (provided if bit D1 of ModeAttributes is set) XResolution dw ? ; horizontal resolution YResolution dw ? ; vertical resolution XCharSize db ? ; character cell width YCharSize db ? ; character cell height NumberOfPlanes db ? ; number of memory planes BitsPerPixel db ? ; bits per pixel NumberOfBanks db ? ; number of banks MemoryModel db ? ; memory model type BankSize db ? ; bank size in kb db 227 DUP(?) ; pad to 256 bytes ENDS vesabuf db 256 DUP(?) modebuf vesamode ? MACRO NEWBANK call [bankadr] ENDM ;***** ;***** initGraphics ;***** PROC C initGraphics cmp [inited],0 je @@NotInited call setMode mov ax,1 retf @@NotInited: call whichVGA or ax,ax ; was function successful? jz @@Error ; no, quit call setMode or ax,ax ; was function successful? jz @@Error ; no, quit call makeAddrTable cmp [vgamem],512 ; ensure enough memory jb @@Error ; abort if <512 K of video RAM mov ax,[bksize] ; initialize bksizeShl10Dec shl ax,10 ; shift it dec ax ; decrement it mov [bksizeShl10Dec],ax ; store it mov ax,1 mov [inited],al retf @@Error: xor ax,ax retf ENDP ;***** ;***** putLine ;***** PROC C putLine_scr_copy ARG lineNum:WORD, xOff:WORD, lineLen:WORD, buf:DATAPTR push ds si di cld mov bx,[lineNum] ; Decide if bank changes mid-line shl bx,1 cmp [cs:bankChanges+bx],0 jne @@BankChanged mov ax,[cs:bankNum+bx] cmp ax,[curBank] ; set bank only if necessary je @@NoNewBank NEWBANK @@NoNewBank: mov cx,[lineLen] ; blast the line into video memory mov ax,0A000h mov es,ax mov di,[cs:lineOffs+bx] add di,[xOff] lds si,[buf] shr cx,1 rep movsw jnc @@Exit movsb @@Exit: pop di si ds leave retf @@BankChanged: ; slow pixel-by-pixel mov cx,[lineLen] mov dx,[lineNum] mov bx,[xOff] lds si,[buf] @@Loop: lodsb push bx cx dx si call far putPixel_scr_copy C,bx,dx,ax pop si dx cx bx inc bx loop @@Loop pop di si ds leave retf ENDP PROC C putLine_mem_copy ARG y:WORD, xOff:WORD, lineLen:WORD, buf:DATAPTR push ds si di ; save these registers xor eax,eax ; clear EAX xor edx,edx ; clear EDX xor edi,edi ; clear EDI les di,[outAddr] ; load output address mov ax,[y] mov dx,[outScreenWide] mul edx ; EDX:EAX = offset - EDI - x add edi,eax ; EDI = offset - x mov dx,[xOff] add edi,edx ; EDI = offset mov edx,edi ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[outSeg] ; DX = new segment mov es,dx ; ES = new segment and di,0000000000001111b ; DI = offset within new segment lds si,[buf] ; load input address mov dx,si ; DX = offset shr dx,4 ; DX = # of paragraphs (segments) mov ax,ds ; AX = DS add ax,dx ; AX = new DS mov ds,ax ; DS = new DS and si,0000000000001111b ; SI = offset within new segment cld mov cx,[lineLen] ; CX = line length mov dx,cx ; DX = line length shr cx,2 ; CX = line length in dwords rep movsd ; move the dwords if necessary mov cx,dx ; CX = line length in bytes and cx,0000000000000011b ; CX = any residual bytes rep movsb ; move the bytes if necessary pop di si ds ; restore registers leave ; clean up retf ; return ENDP ;***** ;***** getLine ;***** PROC C getLine_scr ARG lineNum:WORD, xOff:WORD, lineLen:WORD, buf:DATAPTR push ds si di cld mov bx,[lineNum] ; Decide if bank changes mid-line shl bx,1 cmp [cs:bankChanges+bx],0 jne @@BankChanged mov ax,[cs:bankNum+bx] cmp ax,[curBank] ; set bank only if necessary je @@NoNewBank NEWBANK @@NoNewBank: mov cx,[lineLen] ; blast the line into video memory mov ax,0A000h mov ds,ax mov si,[cs:lineOffs+bx] add si,[xOff] les di,[buf] shr cx,1 rep movsw jnc @@Exit movsb @@Exit: pop di si ds leave retf @@BankChanged: ; slow pixel-by-pixel mov cx,[lineLen] mov dx,[lineNum] mov bx,[xOff] les di,[buf] @@Loop: push bx cx dx di es call far getPixel_scr C,bx,dx pop es di dx cx bx stosb inc bx loop @@Loop pop di si ds leave retf ENDP PROC C getLine_mem ARG y:WORD, xOff:WORD, lineLen:WORD, buf:DATAPTR push ds si di ; save these registers xor eax,eax ; clear EAX xor edx,edx ; clear EDX xor esi,esi ; clear ESI les si,[inAddr] ; load input address mov ax,[y] mov dx,[inScreenWide] mul edx ; EDX:EAX = offset - ESI - x add esi,eax ; ESI = offset - x mov dx,[xOff] add esi,edx ; ESI = offset mov edx,esi ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[inSeg] ; DX = new segment mov ds,dx ; ES = new segment and si,0000000000001111b ; SI = offset within new segment les di,[buf] ; load output address mov dx,di ; DX = offset shr dx,4 ; DX = # of paragraphs (segments) mov ax,es ; AX = ES add ax,dx ; AX = new ES mov es,ax ; ES = new ES and di,0000000000001111b ; DI = offset within new segment cld mov cx,[lineLen] ; CX = line length mov dx,cx ; DX = line length shr cx,2 ; CX = line length in dwords rep movsd ; move the dwords if necessary mov cx,dx ; CX = line length in bytes and cx,0000000000000011b ; CX = any residual bytes rep movsb ; move the bytes if necessary pop di si ds ; restore registers leave ; clean up retf ; return ENDP ;***** ;***** putPixel ;***** ; Copy a pixel to the screen PROC C putPixel_scr_copy ARG x:WORD, y:WORD, colour:BYTE mov bx,[y] ; BX = y coordinate shl bx,1 ; to access a table of words mov ax,[cs:bankNum+bx] ; AX = bank at start of line mov bx,[cs:lineOffs+bx] ; DX = offset at start of line add bx,[x] ; BX = offset of pixel adc ax,0 ; in case of overflow, inc AX mov dx,[bksizeShl10Dec] ; DX = bank size in bytes - 1 cmp bx,dx ; is offset > than bank size jbe @@offsetOK ; no, proceed sub bx,dx ; BX = fixed offset inc ax ; AX = new bank @@offsetOK: cmp ax,[curBank] je @@NoNew NEWBANK ; switch banks if a new bank entered @@NoNew: mov ax,0A000h ; setup screen segment A000 mov es,ax mov al,[colour] ; get color of pixel to plot mov [es:bx],al leave retf ENDP ; Copy a pixel to memory PROC C putPixel_mem_copy ARG x:WORD,y:WORD,colour:BYTE xor eax,eax ; clear EAX xor ebx,ebx ; clear EBX xor edx,edx ; clear EDX les bx,[outAddr] ; load output address mov ax,[y] mov dx,[outScreenWide] mul edx ; EDX:EAX = offset - EBX - x add ebx,eax ; EBX = offset - x mov dx,[x] add ebx,edx ; EBX = offset mov edx,ebx ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[outSeg] ; DX = new segment mov es,dx ; ES = new segment and bx,0000000000001111b ; BX = offset within new segment mov al,[colour] ; colour in AL mov [es:bx],al ; store pixel leave ; clean up retf ; return ENDP ; AND a pixel to memory PROC C putPixel_mem_and ARG x:WORD,y:WORD,colour:BYTE xor eax,eax ; clear EAX xor ebx,ebx ; clear EBX xor edx,edx ; clear EDX les bx,[outAddr] ; load output address mov ax,[y] mov dx,[outScreenWide] mul edx ; EDX:EAX = offset - EBX - x add ebx,eax ; EBX = offset - x mov dx,[x] add ebx,edx ; EBX = offset mov edx,ebx ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[outSeg] ; DX = new segment mov es,dx ; ES = new segment and bx,0000000000001111b ; BX = offset within new segment mov al,[colour] ; colour in AL and [es:bx],al ; AND pixel leave ; clean up retf ; return ENDP ; NOT a pixel to memory PROC C putPixel_mem_not ARG x:WORD,y:WORD,colour:BYTE xor eax,eax ; clear EAX xor ebx,ebx ; clear EBX xor edx,edx ; clear EDX les bx,[outAddr] ; load output address mov ax,[y] mov dx,[outScreenWide] mul edx ; EDX:EAX = offset - EBX - x add ebx,eax ; EBX = offset - x mov dx,[x] add ebx,edx ; EBX = offset mov edx,ebx ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[outSeg] ; DX = new segment mov es,dx ; ES = new segment and bx,0000000000001111b ; BX = offset within new segment mov al,[colour] ; colour in AL not al ; NOT it mov [es:bx],al ; store NOTed pixel leave ; clean up retf ; return ENDP ; OR a pixel to memory PROC C putPixel_mem_or ARG x:WORD,y:WORD,colour:BYTE xor eax,eax ; clear EAX xor ebx,ebx ; clear EBX xor edx,edx ; clear EDX les bx,[outAddr] ; load output address mov ax,[y] mov dx,[outScreenWide] mul edx ; EDX:EAX = offset - EBX - x add ebx,eax ; EBX = offset - x mov dx,[x] add ebx,edx ; EBX = offset mov edx,ebx ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[outSeg] ; DX = new segment mov es,dx ; ES = new segment and bx,0000000000001111b ; BX = offset within new segment mov al,[colour] ; colour in AL or [es:bx],al ; OR pixel leave ; clean up retf ; return ENDP ; XOR a pixel to memory PROC C putPixel_mem_xor ARG x:WORD,y:WORD,colour:BYTE xor eax,eax ; clear EAX xor ebx,ebx ; clear EBX xor edx,edx ; clear EDX les bx,[outAddr] ; load output address mov ax,[y] mov dx,[outScreenWide] mul edx ; EDX:EAX = offset - EBX - x add ebx,eax ; EBX = offset - x mov dx,[x] add ebx,edx ; EBX = offset mov edx,ebx ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[outSeg] ; DX = new segment mov es,dx ; ES = new segment and bx,0000000000001111b ; BX = offset within new segment mov al,[colour] ; colour in AL xor [es:bx],al ; XOR pixel leave ; clean up retf ; return ENDP ;***** ;***** getPixel ;***** ; Get a pixel from the screen PROC C getPixel_scr ARG x:WORD, y:WORD mov bx,[y] ; BX = y coordinate shl bx,1 ; to access a table of words mov ax,[cs:bankNum+bx] ; AX = bank at start of line mov bx,[cs:lineOffs+bx] ; DX = offset at start of line add bx,[x] ; BX = offset of pixel adc ax,0 ; in case of overflow, inc AX mov dx,[bksizeShl10Dec] ; DX = bank size in bytes - 1 cmp bx,dx ; is offset > than bank size jb @@offsetOK ; no, proceed sub bx,dx ; BX = fixed offset inc ax ; AX = new bank @@offsetOK: cmp ax,[curBank] je @@NoNew NEWBANK ; switch banks if a new bank entered @@NoNew: mov ax,0A000h ; setup screen segment A000 mov es,ax mov al,[es:bx] ; AL = colour for return leave retf ENDP ; Get a pixel from memory PROC C getPixel_mem ARG x:WORD,y:WORD xor eax,eax ; clear EAX xor ebx,ebx ; clear EBX xor edx,edx ; clear EDX les bx,[inAddr] ; load input address mov ax,[y] mov dx,[inScreenWide] mul edx ; EDX:EAX = offset - EBX - x add ebx,eax ; EBX = offset - x mov dx,[x] add ebx,edx ; EBX = offset mov edx,ebx ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[inSeg] ; DX = new segment mov es,dx ; ES = new segment and bx,0000000000001111b ; BX = offset within new segment xor ax,ax ; clear AX mov al,[es:bx] ; store pixel in AX for return leave ; clean up retf ; return ENDP ;***** ;***** horizLine ;***** PROC C horizLine_scr_copy ARG y:WORD, x1:WORD, x2:WORD, colour:BYTE push di cld mov bx,[y] ; Decide if bank changes mid-line shl bx,1 cmp [cs:bankChanges+bx],0 jne @@BankChanged mov ax,[cs:bankNum+bx] cmp ax,[curBank] ; set bank only if necessary je @@NoNewBank NEWBANK @@NoNewBank: mov ax,0A000h mov es,ax mov ax,[x1] mov di,[cs:lineOffs+bx] add di,ax mov cx,[x2] ; blast the line into video memory inc cx sub cx,ax mov al,[colour] mov ah,al shr cx,1 rep stosw jnc @@Exit stosb @@Exit: pop di leave retf @@BankChanged: ; slow pixel-by-pixel mov bx,[x1] mov cx,[x2] inc cx sub cx,bx mov dx,[y] @@Loop: push bx cx dx mov al,[colour] call far putPixel_scr_copy C,bx,dx,ax pop dx cx bx inc bx loop @@Loop pop di leave retf ENDP PROC C horizLine_mem_copy ARG y:WORD, x1:WORD, x2:WORD, colour:BYTE push edi ; store EDI xor eax,eax ; clear EAX xor edi,edi ; clear EDI xor edx,edx ; clear EDX les di,[outAddr] ; load output address mov ax,[y] mov dx,[outScreenWide] mul edx ; EDX:EAX = offset - EDI - x add edi,eax ; EDI = offset - x mov dx,[x1] add edi,edx ; EDI = offset mov edx,edi ; EDX = offset shr edx,4 ; EDX = # of paragraphs (segments) add dx,[outSeg] ; DX = new segment mov es,dx ; ES = new segment and di,0000000000001111b ; DI = offset within new segment mov al,[colour] ; colour in AL mov ah,al ; colour in AH mov bx,ax shl eax,16 mov ax,bx ; colour in each byte of EAX mov cx,[x2] sub cx,[x1] inc cx ; CX = line length in pixels mov dx,cx ; DX = line length in bytes shr cx,2 ; CX = line length in dwords rep stosd ; store four bytes at a time mov cx,dx ; CX = line length in pixels and cx,0000000000000011b ; CX = any remaining bytes rep stosb ; store the remaining bytes pop edi ; restore EDI leave ; clean up retf ; return ENDP ;***** ;***** setPaletteReg ;***** PROC C setPaletteReg ARG palNum:WORD,red:BYTE,green:BYTE,blue:BYTE mov bx,[palNum] mov dx,3C8h ; set for correct palette register mov ax,[palNum] out dx,al inc dx mov al,[red] ; red shr al,2 jnc @@L1 cmp al,63 je @@L1 inc al @@L1: out dx,al mov al,[green] ; green shr al,2 jnc @@L2 cmp al,63 je @@L2 inc al @@L2: out dx,al mov al,[blue] ; blue shr al,2 jnc @@L3 cmp al,63 je @@L3 inc al @@L3: out dx,al leave retf ENDP ;***** ;***** getPaletteReg ;***** PROC C getPaletteReg ARG palNum:WORD,red:DATAPTR,green:DATAPTR,blue:DATAPTR push ds si mov dx,3C7h ; set for correct palette register mov ax,[palNum] out dx,al mov dx,3C9h in al,dx ; red lds si,[red] shl al,2 mov [ds:si],al in al,dx ; green lds si,[green] shl al,2 mov [ds:si],al in al,dx ; blue lds si,[blue] shl al,2 mov [ds:si],al pop si ds leave retf ENDP ;***** ;***** setBlockPalette ;***** PROC C setBlockPalette ARG firstReg:WORD,lastReg:WORD,paletteData:DATAPTR push ds si lds si,[paletteData] ; set up mov dx,3C8h mov ax,[firstReg] out dx,al inc dx mov cx,[lastReg] ; CX = number of registers sub cx,ax inc cx cld @@LLoop: lodsb ; red shr al,2 jnc @@L1 cmp al,63 je @@L1 inc al @@L1: out dx,al lodsb ; green shr al,2 jnc @@L2 cmp al,63 je @@L2 inc al @@L2: out dx,al lodsb ; blue shr al,2 jnc @@L3 cmp al,63 je @@L3 inc al @@L3: out dx,al loop @@LLoop @@LExit: pop si ds leave retf ENDP ;***** ;***** getBlockPalette ;***** PROC C getBlockPalette ARG firstReg:WORD,lastReg:WORD,paletteData:DATAPTR push di les di,[paletteData] ; set up mov dx,3C7h mov ax,[firstReg] out dx,al mov dx,3C9h mov cx,[lastReg] ; CX = number of registers sub cx,ax inc cx cld @@L1: in al,dx shl al,2 stosb ; red in al,dx shl al,2 stosb ; green in al,dx shl al,2 stosb ; blue loop @@L1 @@LExit: pop di leave retf ENDP ;***** ;***** Bank switching routines ;***** _acumos: ; AcuMos push ax dx ax cli mov [curBank],ax mov dx,3C4h ; sequencer index 6 mov ax,1206h ; disable write protect on VGA registers out dx,ax mov dx,3CEh pop ax mov ah,al mov al,9 out dx,ax sti pop dx ax ret _aheada: ; Ahead Systems Ver A push ax dx cx cli mov [curBank],ax mov ch,al mov dx,3CEh ; Enable extended registers mov ax,200Fh out dx,ax mov dl,0CCh ; bit 0 in al,dx mov dl,0C2h and al,11011111b shr ch,1 jnc @@skpa or al,00100000b @@skpa: out dx,al mov dl,0CFh ; bits 1,2,3 xor al,al out dx,al inc dx in al,dx dec dx and al,11111000b or al,ch mov ah,al xor al,al out dx,ax sti pop cx dx ax ret _aheadb: ; Ahead Systems Ver B push ax dx cx cli mov [curBank],ax mov ch,al mov dx,3CEh ; Enable extended registers mov ax,200Fh out dx,ax mov ah,ch mov cl,4 shl ah,cl or ah,ch mov al,0Dh out dx,ax sti pop cx dx ax ret _ativga: ; ATI VGA Wonder push ax dx cli mov [curBank],ax mov ah,al mov dx,1CEh mov al,0B2h out dx,al inc dl in al,dx shl ah,1 and al,0E1h or ah,al mov al,0B2h dec dl out dx,ax sti pop dx ax ret _chipstech: ; Chips & Tech push ax dx ax cli mov [curBank],ax mov dx,46E8h ; place chip in setup mode mov ax,1Eh out dx,ax mov dx,103h ; enable extended registers mov ax,0080h out dx,ax mov dx,46E8h ; bring chip out of setup mode mov ax,0Eh out dx,ax pop ax mov ah,al mov al,10h mov dx,3D6h out dx,ax sti pop dx ax ret _cirrus: ; Cirrus push ax dx cli mov [curBank],ax mov dx,3CEh mov ah,al mov al,9 out dx,ax sti pop dx ax ret _compaq: ; Compaq push ax dx ax cli mov [curBank],ax mov dx,3CEh mov ax,50Fh ; unlock extended registers out dx,ax pop ax mov ah,al mov al,45h out dx,ax sti pop dx ax ret _everex: ; Everex push ax dx cx cli mov [curBank],ax mov cl,al mov dx,3C4h mov al,8 out dx,al inc dl in al,dx dec dl shl al,1 shr cl,1 rcr al,1 mov ah,al mov al,8 out dx,ax mov dl,0CCh in al,dx mov dl,0C2h and al,0DFh shr cl,1 jc @@nob2 or al,20h @@nob2: out dx,al sti pop cx dx ax ret _genoa: ; GENOA GVGA push ax dx cli mov [curBank],ax mov ah,al shl al,3 or ah,al mov al,6 or ah,40h mov dx,3C4h out dx,ax sti pop dx ax ret _ncr: ; NCR 77C22E push ax dx cli mov [curBank],ax mov ah,al mov al,18h mov dx,3C4h out dx,ax mov ax,19h out dx,ax sti pop dx ax ret _oak067: ; Oak Technology OTI-067 push ax dx cli mov [curBank],ax and al,15 mov ah,al shl al,4 or ah,al mov al,11h mov dx,3DEh out dx,ax sti pop dx ax ret _paradise: ; Paradise push ax dx cli mov [curBank],ax mov dx,3CEh mov ah,al shl ah,4 ; 64K bank number -> 4K bank number mov al,09h ; program PR0A out dx,ax mov al,0Ah ; program PR0B out dx,ax sti pop dx ax ret _trident: ; Trident push ax dx ax cli mov [curBank],ax mov dx,3CEh ; set pagesize to 64k mov al,6 out dx,al inc dl in al,dx dec dl or al,4 mov ah,al mov al,6 out dx,ax mov dl,0C4h ; switch to BPS mode mov al,0Bh out dx,al inc dl in al,dx dec dl pop ax mov ah,al xor ah,2 mov dx,3C4h mov al,0Eh out dx,ax sti pop dx ax ret _tseng: ; Tseng push ax dx cli mov [curBank],ax and al,7 mov ah,al shl al,3 or al,ah or al,01000000b mov dx,3CDh out dx,al sti pop dx ax ret _tseng4: ; Tseng 4000 series ; push ax dx ; cli ; mov [curBank],ax ; mov ah,al ; mov dx,3BFh ; enable access to extended registers ; mov al,3 ; out dx,al ; mov dl,0D8h ; mov al,0A0h ; out dx,al ; and ah,15 ; mov al,ah ; shl al,4 ; or al,ah ; mov dl,0CDh ; out dx,al ; sti ; pop dx ax ; ret push ax dx cli mov [curBank],ax and al,0Fh mov ah,al shl ah,4 or al,ah mov dx,3CDh out dx,al sti pop dx ax ret _video7: ; Video 7 push ax dx cx cli mov [curBank],ax and ax,15 mov ch,al mov dx,3C4h mov ax,0EA06h out dx,ax mov ah,ch and ah,1 mov al,0F9h out dx,ax mov al,ch and al,1100b mov ah,al shr ah,2 or ah,al mov al,0F6h out dx,al inc dx in al,dx dec dx and al,NOT 1111b or ah,al mov al,0F6h out dx,ax mov ah,ch mov cl,4 shl ah,cl and ah,100000b mov dl,0CCh in al,dx mov dl,0C2h and al,NOT 100000b or al,ah out dx,al sti pop cx dx ax ret _vesa: ; Vesa SVGA interface push ax bx dx cli mov [curBank],ax mov dx,ax xor bx,bx mov ax,4F05h int 10h sti pop dx bx ax ret _nobank: cli mov [curBank],ax sti ret MACRO BKADR func mov [func],1 mov [bankadr],OFFSET _&func ENDM MACRO NOJMP local lbl jmp short lbl lbl: ENDM PROC whichVGA NEAR push si di cmp [inited],1 jne @@goTest mov ax,[retval] pop di si ret @@goTest: mov [bankadr],OFFSET _nobank ; Initialize variables mov [vgamem],256 mov [bksize],64 xor ax,ax mov [curBank],ax mov [acumos],ax mov [aheada],ax mov [aheadb],ax mov [ativga],ax mov [chipstech],ax mov [cirrus],ax mov [compaq],ax mov [everex],ax mov [genoa],ax mov [ncr],ax mov [oak067],ax mov [paradise],ax mov [trident],ax mov [t8900],ax mov [tseng],ax mov [tseng4],ax mov [video7],ax mov [vesa],ax mov si,1 ; success code; changed on error mov ax,cs ; Test for VESA mov es,ax mov di,OFFSET vesabuf mov ax,4F00h int 10h cmp ax,004Fh jne @@noVESA BKADR vesa mov [bksize],64 ; assume 64 K bank size (for now) mov [vgamem],512 ; assume 512 K if VESA jmp @@fini @@noVESA: mov ax,0C000h ; Test for ATI mov es,ax cmp [word ptr es:40h],'13' ; ATI Signiture on the Video BIOS jnz @@noATI BKADR ativga mov [bksize],64 ; 64K bank size mov dx,[es:10h] ; get value of ATI extended register mov bl,[es:43h] ; get value of ATI chip version cmp bl,'3' jae @@v6up ; use different method to find memory size mov al,0BBh cli out dx,al inc dx in al,dx sti test al,20h jz @@no512 mov [vgamem],512 jmp short @@no512 @@v6up: mov al,0B0h ; method for newer ATIs cli out dx,al inc dx in al,dx ; get RAM size for versions 3-5 sti test al,10h ; check if 256 K or 512 K jz @@v7up mov [vgamem],512 @@v7up: cmp bl,'4' ; get RAM size for versions 4 & 5 jb @@no512 test al,8 ; check if version 5 chip has 1024 K jz @@no512 mov [vgamem],1024 @@no512: jmp @@fini @@noATI: mov ax,7000h ; Test for Everex xor bx,bx cld int 10h cmp al,70h jnz @@noEverex BKADR everex mov [bksize],64 ; 64 K bank size and ch,11000000b ; how much memory on board? jz @@skp mov [vgamem],512 @@skp: ; fall through for Everex boards using Trident or Tseng4000 @@noEverex: mov ax,0BF03h ; Test for Compaq xor bx,bx mov cx,bx int 10h cmp ax,0BF03h jnz @@noCompaq test cl,40h ; is 640x480x256 available? jz @@noCompaq BKADR compaq mov [bksize],4 ; 4 K bank size mov [vgamem],512 jmp @@fini @@noCompaq: mov dx,3C4h ; Test for NCR 77C22E mov ax,0FF05h call _isport2 jnz @@noNCR mov ax,5 ; Disable extended registers out dx,ax mov ax,0FF10h ; Try to write to extended register 10 call _isport2 ; If it writes then not NCR jz @@noNCR mov ax,105h ; Enable extended registers out dx,ax mov ax,0FF10h call _isport2 jnz @@noNCR ; If it does NOT write then not NCR BKADR ncr mov [bksize],16 ; 16 K bank size mov [vgamem],512 jmp @@fini @@noNCR: mov dx,3C4h ; Test for Trident mov al,0Eh ; Read mode control register #1 out dx,al inc dx in al,dx ; Read old value xor al,2 push ax xor al,al ; Write new value bit 1=0, all other bits=0 out dx,al in al,dx ; Read new value and al,0Fh cmp al,2 ; Check for Trident pop ax ; Old value in AX out dx,al ; Restore old value jne @@noTrident BKADR trident ; Trident found mov [bksize],64 dec dx ; Distinguish 8800/8900 mov al,0Bh ; Index of version register out dx,al ; Select version register inc dx xor al,al out dx,al ; Dummy write to force old definitions in al,dx ; Read causes new definitions cmp al,3 ; Is it 8900+? jb @@Trident8800 ; no, 8800 mov [t8900],1 ; yes mov dx,3D5h mov al,1Fh out dx,al inc dx in al,dx and al,3 cmp al,1 jb @@noTmem mov [vgamem],512 je @@noTmem mov [vgamem],1024 @@noTmem: jmp @@fini @@Trident8800: mov [vgamem],512 jmp @@fini @@noTrident: mov ax,6F00h ; Test for Video 7 xor bx,bx cld int 10h cmp bx,'V7' jnz @@noVideo7 BKADR video7 mov [bksize],64 ; 64 K bank size mov ax,6F07h cld int 10h and ah,7Fh cmp ah,1 jbe @@skp2 mov [vgamem],512 @@skp2: cmp ah,3 jbe @@skp3 mov [vgamem],1024 @@skp3: jmp @@fini @@noVideo7: mov dx,3D4h ; Test for GENOA GVGA mov ax,032Eh ; check for Herchi Register call _isport2 jnz @@noGenoa mov dx,3C4h ; check for memory segment register mov ax,3F06h call _isport2 jnz @@noGenoa BKADR genoa mov [bksize],64 ; 64 K bank size mov [vgamem],512 jmp @@fini @@noGenoa: call cirrusDetect ; Test for Cirrus cmp [cirrus],0 je @@noCirrus jmp @@fini @@noCirrus: mov dx,3CEh ; Test for Paradise mov al,9 ; check Bank switch register out dx,al inc dx in al,dx dec dx or al,al jnz @@noParadise mov ax,50Fh ; turn off write protect on VGA registers out dx,ax mov dx,OFFSET _paradise mov cx,1 call _chkbk jc @@noParadise ; if bank 0 and 1 same not paradise BKADR paradise ; mov [bksize],4 ; 4 K bank size mov [bksize],64 ; Disable write-protect of VGA registers mov ax,050Fh mov dx,3CEh out dx,ax ; Unlock extended sequencer registers mov ax,4806h mov dx,3C4h out dx,ax ; Enable access to PR10-17 mov ax,8529h mov dx,3D4h out dx,ax ; Allow access to all SVGA memory mov dx,3D4h mov al,2Fh out dx,al inc dx in al,dx and al,NOT 2 out dx,al ; Enable PR0A and PR0B mov dx,3CEh mov al,0Bh out dx,al inc dx in al,dx and al,NOT 8 or al,8 out dx,al ; Set PR0A for read, PR0B for write mov dx,3C4h mov al,11h out dx,al inc dx in al,dx and al,NOT 80h or al,80h out dx,al mov dx,3CEh mov al,0Bh ; 512k detect from out dx,al inc dx in al,dx test al,80h ; if top bit set then 512k jz @@nop512 mov [vgamem],512 @@nop512: jmp @@fini @@noParadise: mov ax,5F00h ; Test for Chips & Tech xor bx,bx cld int 10h cmp al,5Fh jnz @@noChipsTech BKADR chipstech mov [bksize],16 ; 16 K bank size cmp bh,1 jb @@skp4 mov [vgamem],512 cmp bh,2 jb @@skp4 mov [vgamem],1024 @@skp4: jmp @@fini @@noChipsTech: xor ch,ch ; check for Tseng 4000 series mov dx,3D4h mov ax,0F33h call _isport2 jnz @@noTseng4 mov ch,1 mov dx,3BFh ; Enable access to extended registers mov al,3 out dx,al mov dx,3D8h mov al,0A0h out dx,al jmp short @@yes4 @@noTseng4: mov dx,3D4h ; Test for Tseng 3000 or 4000 mov ax,1F25h ; is the Overflow High register there? call _isport2 jnz @@noTseng mov al,03Fh ; bottom six bits only jmp short @@yes3 @@yes4: mov al,0FFh @@yes3: mov dx,3CDh ; test bank switch register call _isport1 jnz @@noTseng BKADR tseng mov [bksize],64 ; 64 K bank size or ch,ch jnz @@t4mem mov [vgamem],512 jmp @@fini @@t4mem: mov dx,3D4h ; Tseng 4000 memory detect 1meg mov al,37h out dx,al inc dx in al,dx test al,1000b ; if using 64kx4 RAMs then no more than 256k jz @@nomem and al,3 cmp al,1 ; if 8 bit wide bus then only two 256kx4 RAMs jbe @@nomem mov [vgamem],512 cmp al,2 ; if 16 bit wide bus then four 256kx4 RAMs je @@nomem mov [vgamem],1024 ; full meg with eight 256kx4 RAMs @@nomem: ; Special setup for ET4000 mov dx,3BFh mov al,3 out dx,al mov dl,0D8h mov al,0A0h out dx,al BKADR tseng4 jmp @@fini @@noTseng: mov dx,3CEh ; Test for Above A or B chipsets mov ax,200Fh out dx,ax inc dx NOJMP in al,dx cmp al,21h jz @@verB cmp al,20h jnz @@noAbove BKADR aheada mov [bksize],64 ; 64 K bank size mov [vgamem],512 jmp @@fini @@verB: BKADR aheadb mov [bksize],64 ; 64 K bank size mov [vgamem],512 jmp @@fini @@noAbove: mov dx,3C4h ; Test for AcuMos chipsets mov ax,0006h out dx,ax mov ax,0FF09h call _isport2 ; is scratchpad at index 9 writeable? jz @@noAcumos mov ax,0FF0Ah call _isport2 ; is scratchpad at index 10 writeable? jz @@noAcumos mov ax,1206h out dx,ax mov ax,0FF09h call _isport2 jnz @@noAcumos mov ax,0FF0Ah call _isport2 jnz @@noAcumos mov dx,OFFSET _acumos mov cx,1 call _chkbk jc @@noAcumos BKADR acumos mov [bksize],4 ; 4 K bank size mov dx,3C4h mov al,0Ah out dx,al inc dx in al,dx and al,3 cmp al,1 jb @@noAcumosMem mov [vgamem],512 cmp al,2 jb @@noAcumosMem mov [vgamem],1024 cmp al,3 jb @@noAcumosMem mov [vgamem],2048 @@noAcumosMem: jmp short @@fini @@noAcumos: mov dx,3DEh ; Test for Oak Technology mov ax,0FF11h ; look for bank switch register call _isport2 jnz @@fini BKADR oak067 mov [bksize],64 ; 64 K bank size mov al,0Dh out dx,al inc dx NOJMP in al,dx test al,11000000b jz @@fini mov [vgamem],512 test al,01000000b jz @@fini mov [vgamem],1024 jmp short @@fini @@noSVGA: xor si,si ; set error flag @@fini: mov ax,si ; success code in AX for return mov [retval],ax pop di si ret ENDP PROC cirrusDetect NEAR mov dx,3D4h ; assume 3dx addressing mov al,0Ch ; screen a start address hi out dx,al ; select index inc dx ; point to data mov ah,al ; save index in ah in al,dx ; get screen a start address hi xchg ah,al ; swap index and data push ax ; save old value push dx ; save crtc address xor al,al ; clear crc out dx,al ; and out to the crtc mov al,1Fh ; Eagle ID register dec dx ; back to index out dx,al ; select index inc dx ; point to data in al,dx ; read the id register mov bh,al ; and save it in bh mov cl,4 ; nibble swap rotate count mov dx,3C4h ; sequencer/extensions mov bl,6 ; extensions enable register ror bh,cl ; compute extensions disable value mov ax,bx ; extensions disable out dx,ax ; disable extensions inc dx ; point to data in al,dx ; read enable flag or al,al ; disabled ? jnz @@Exit ; nope, not an cirrus ror bh,cl ; compute extensions enable value dec dx ; point to index mov ax,bx ; extensions enable out dx,ax ; enable extensions inc dx ; point to data in al,dx ; read enable flag cmp al,1 ; enabled ? jne @@Exit ; nope, not a Cirrus mov dx,3C4h ; Cirrus found -- get size of memory mov al,0Fh out dx,al inc dx in al,dx shr al,3 and al,3 cmp al,1 jb @@Exit ; only 256 K mov [vgamem],512 cmp al,2 jb @@Setup ; 512 K mov [vgamem],1024 ; 1 meg @@Setup: mov [cirrus],1 BKADR cirrus mov [bksize],4 @@Exit: pop dx ; restore crtc address dec dx ; point to index pop ax ; recover crc index and data out dx,ax ; restore crc value ret ENDP PROC _chkbk NEAR ; bank switch check routine mov di,0B800h mov es,di xor di,di mov bx,1234h call _gochk jnz @@badchk mov bx,4321h call _gochk jnz @@badchk clc ret @@badchk: stc ret ENDP PROC _gochk NEAR push si mov si,bx mov al,cl call dx xchg bl,[es:di] mov al,ch call dx xchg bh,[es:di] xchg si,bx mov al,cl call dx xor bl,[es:di] mov al,ch call dx xor bh,[es:di] xchg si,bx mov al,ch call dx mov [es:di],bh mov al,cl call dx mov [es:di],bl xor al,al call dx or si,si pop si ret ENDP PROC _isport2 NEAR ; check for valid I/O port ; AL is index, AH is bit mask push bx mov bx,ax out dx,al mov ah,al inc dx in al,dx dec dx xchg al,ah push ax mov ax,bx out dx,ax out dx,al mov ah,al inc dx in al,dx dec dx and al,bh cmp al,bh jnz @@noport mov al,ah xor ah,ah out dx,ax out dx,al mov ah,al inc dx in al,dx dec dx and al,bh cmp al,0 @@noport: pop ax out dx,ax pop bx ret ENDP PROC _isport1 NEAR ; check for valid I/O port ; AL is bit mask mov ah,al in al,dx push ax mov al,ah out dx,al in al,dx and al,ah cmp al,ah jnz @@noport xor al,al out dx,al in al,dx and al,ah cmp al,0 @@noport: pop ax out dx,al ret ENDP PROC setMode NEAR ; Set 640x480x256 mov [scanline],SCREEN_WIDE cmp [vesa],0 jz @@noVESA mov bx,101h call VESAset or ax,ax ; was function successful? JUMPS jz @@noSVGA ; no, quit NOJUMPS jmp @@godo2 @@noVESA: cmp [compaq],0 jz @@noCompaq mov [scanline],1024 mov ax,2Eh jmp @@godo @@noCompaq: cmp [genoa],0 jz @@noGenoa mov ax,5Ch jmp @@godo @@noGenoa: cmp [ncr],0 jz @@noNCR mov ax,5Fh jmp @@godo @@noNCR: cmp [oak067],0 jz @@noOak067 mov ax,53h jmp @@godo @@noOak067: cmp [aheada],0 jnz @@ cmp [aheadb],0 jz @@noAbove @@: mov ax,61h jmp @@godo @@noAbove: cmp [everex],0 jz @@noEverex mov ax,70h mov bl,30h jmp short @@godo @@noEverex: cmp [ativga],0 jz @@noATI mov ax,62h jmp short @@godo @@noATI: cmp [trident],0 jz @@noTrident mov ax,5Dh jmp short @@godo @@noTrident: cmp [video7],0 jz @@noVideo7 mov ax,6F05h mov bl,67h jmp short @@godo @@noVideo7: cmp [chipstech],0 jz @@noChipsTech mov ax,79h jmp short @@godo @@noChipsTech: cmp [cirrus],0 jz @@noCirrus mov ax,5Fh jmp short @@godo @@noCirrus: cmp [acumos],0 jnz @@doParadise cmp [paradise],0 jz @@noParadise @@doParadise: mov ax,5Fh jmp short @@godo @@noParadise: cmp [tseng],0 jz @@noSVGA mov ax,2Eh @@godo: int 10h @@godo2: mov [curBank],-1 mov ax,1 ; return success code ret @@noSVGA: xor ax,ax ; return error code ret ENDP PROC VESAset NEAR push di push bx mov ax,4F02h int 10h ; set the mode pop cx or ah,ah ; was function successful? jz @@noError ; yes xor ax,ax ; set error code (for setMode) jmp short @@Exit @@noError: mov ax,cs mov es,ax mov di,OFFSET modebuf mov ax,4F01h int 10h ; get the mode information mov ax,[modebuf.WinSize] mov [bksize],ax mov ax,[modebuf.BytesPerLine] mov [scanline],ax mov ax,1 ; set success code (for setMode) @@Exit: pop di ret ENDP PROC makeAddrTable NEAR LOCAL temp:WORD push si di mov si,OFFSET lineOffs mov di,OFFSET bankNum xor bx,bx ; current line number = 0 mov ax,[bksize] ; separate process if bksize=64 K cmp ax,64 je @@64kBnk mov cl,10 shl ax,cl ; AX = bank size in bytes dec ax mov [temp],ax ; [temp] = banksize in bytes - 1 mov ax,[bksize] ; AX = bank size in K @@shlp: inc cl shr ax,1 jnz @@shlp ; loop until AX = 0 dec cx xor ax,ax ; AX = 0 xor dx,dx ; DX = 0 @@lp: push ax ; store AX shr ax,cl add dx,ax ; update current bank number pop ax ; restore AX and ax,[temp] ; mask offset so it's < bank size mov [cs:si],ax ; save line offset add si,2 ; update pointer mov [cs:di],dx ; save bank number add di,2 ; update pointer add ax,[scanline] ; update offset inc bx ; update line number cmp bx,SCREEN_DEEP jb @@lp ; loop until all lines done jmp short @@calcBankChange ; calculate bank change table @@64kBnk: xor ax,ax ; AX = 0 xor dx,dx ; DX = 0 mov cx,[scanline] ; CX = width of line in bytes @@nlp: mov [cs:si],ax ; store line offset add si,2 ; update pointer mov [cs:di],dx ; store bank number add di,2 ; update pointer add ax,cx ; add another line width adc dx,0 ; increase bank number if overflow inc bx ; update current line number cmp bx,SCREEN_DEEP jb @@nlp ; jump until all lines done @@calcBankChange: mov di,OFFSET bankChanges ; initialize pointer xor ax,ax ; AX = current line @@bankChangeLoop: mov bx,ax ; BX = current line shl bx,1 ; to access a table of words mov dx,[cs:bankNum+bx] ; DX = bank at start of current line mov bx,ax ; BX = current line inc bx ; BX = next line shl bx,1 ; to access a table of words mov cx,[cs:bankNum+bx] ; CX = bank at start of next line mov si,[cs:lineOffs+bx] ; SI = offset at start of next line or si,si ; is SI=0? jz @@L1 ; yes, jump dec cx ; CX = bank at end of current line @@L1: cmp cx,dx ; are start and end banks the same? jne @@newBank ; bank changed, jump mov [word ptr cs:di],1 ; store bank changed flag jmp short @@L2 ; jump @@newBank: mov [word ptr cs:di],0 ; store bank same flag @@L2: add di,2 ; update pointer inc ax ; update current line number cmp ax,SCREEN_DEEP jb @@bankChangeLoop ; loop until all lines done pop di si ret ENDP ENDS END