;**************************************************************************** ;* ;* The Universal VESA TSR ;* ;* Copyright (C) 1993 Kendall Bennett. ;* All rights reserved. ;* ;* Filename: $RCSfile: univesa.asm $ ;* Version: $Revision: 1.2 $ ;* ;* Language: 80386 Assembler ;* Environment: IBM PC (MS DOS) ;* ;* Description: This source file contains the code for a Universal VESA ;* TSR's, to implement the VESA video BIOS extensions for ;* supported SuperVGA's. ;* ;* Must be assembled in the large memory model. ;* ;* $Id: univesa.asm 1.2 1993/03/07 04:05:36 kjb Exp $ ;* ;* Revision History: ;* ----------------- ;* ;* $Log: univesa.asm $ ;* Revision 1.2 1993/03/07 04:05:36 kjb ;* Bug fixes. ;* ;* Revision 1.1 1993/03/03 10:27:33 kjb ;* Initial revision ;* ;**************************************************************************** IDEAL DOSSEG JUMPS P386 ; Use 386 instructions INCLUDE "MODEL.MAC" ; Memory model macros header uvesa ; Link with uvesa.c ;---------------------------------------------------------------------------- ; Internal Equates and Macros ;---------------------------------------------------------------------------- INCLUDE "MGRAPH.EQU" ; Include Equates for Mgraph Routines CRTC EQU 3D4h ; Port of CRTC registers VGABufferSeg EQU 0A000h ; Segment of VGA display memory NL EQU <0dh, 0ah> ; New Line marker EOS EQU '$' ; End of String marker PSPSize EQU 100h ; Size of program PSP SUCCESS EQU 004Fh ; Return value on success FAILURE EQU 014Fh ; Return value on failure VESA_FUNCTIONS EQU 04Fh ; VESA Control function value (AH) MAX_FUNCTION EQU 7 ; Highest VESA function number supported VESA_VERSION EQU 0102h ; Version 1.2 ; Macro to get the value of an interrupt vector. Returns the result in ; ES:BX. MACRO GetVector intnum mov ah,35h mov al,intnum int 21h ENDM ; Macro to set the value of an interrupt vector. MACRO SetVector intnum, handler push ds mov dx,seg handler mov ds,dx mov dx,offset handler mov ah,25h mov al,intnum int 21h pop ds ENDM begcodeseg uvesa EXTRN _testISR:FAR endcodeseg uvesa begcodeseg modes EXTRN _MGL_availableModes:FAR endcodeseg modes begcodeseg uvesa ;---------------------------------------------------------------------------- ; Resident Data ;---------------------------------------------------------------------------- ; Signature used to determine if the TSR is already installed. Signature: db 'Universal VESA TSR',0 SigLen = $-Signature LABEL OldInt10 DWORD OldInt10off dw ? ; Place to save int 10h vector OldInt10seg dw ? ; Globals used by resident generic SuperVGA routines CntDriver dw 0 ; Graphics driver number CntMode dw 0 ; Graphics mode number CntDAC dw 0 ; Video DAC ID CntChipID dw 0 ; Graphics driver chip ID CntColors dw 0 ; Current color mode CntVESAMode dw 0 ; Current VESA mode number CntMemory dw 0 ; Amount of memory on chip CntStartX dw 0 ; Current display start X CntStartY dw 0 ; Current display start Y ; Dispatch table for supported function calls DispatchTable dw offset SuperVGAInfo dw offset SuperVGAModeInfo dw offset SuperVGASetMode dw offset SuperVGAGetMode dw offset SuperVGAVideoState dw offset SuperVGABankSwitch dw offset SuperVGAScanlineLength dw offset SuperVGADisplayStart Status dw 0 ; Return status code ; VGA Information block returned to the user program VGAInfo db 'VESA' ; Signature value dw VESA_VERSION ; VESA Version number dw offset Signature ; OEM Name offset dw seg Signature ; OEM Name segment db 4 DUP (0) ; Capabilities bits dw offset ModeTable ; Video mode table offset dw seg ModeTable ; Video mode table segment VGAInfoSize = $-VGAInfo ; List of all possible supported VESA video modes. If any of the modes ; are not supported by the installed SuperVGA, they are zeroed from the ; table. ModeTable dw 100h ; grSVGA_640x400x256 dw 101h ; grSVGA_640x480x256 dw 102h ; grSVGA_800x600x16 dw 103h ; grSVGA_800x600x256 dw 104h ; grSVGA_1024x768x16 dw 105h ; grSVGA_1024x768x256 dw 106h ; grSVGA_1280x1024x16 dw 107h ; grSVGA_1280x1024x256 dw 10Dh ; grSVGA_320x200x32k dw 10Fh ; grSVGA_320x200x16m dw 110h ; grSVGA_640x480x32k dw 112h ; grSVGA_640x480x16m dw 113h ; grSVGA_800x600x32k dw 115h ; grSVGA_800x600x16m dw 116h ; grSVGA_1024x768x32k dw 118h ; grSVGA_1024x768x16m dw 119h ; grSVGA_1280x1024x32k dw 11Bh ; grSVGA_1280x1024x16m dw 0FFFFh ; Terminate the list ; Define the memory model type numbers memPL16 EQU 3 ; Planar memPK256 EQU 4 ; Packed pixel memPKD EQU 6 ; Direct ; Video mode information for the currently active video mode. BIOS ; output is generally supported by most video modes, but we can never ; be sure so we turn this off for all modes. ModeInfo dw 011011b ; Mode Attributes db 0111b ; Window A attributes WinBAttr db 0011b ; Window B attributes dw 64 ; Window granularity (in K) dw 64 ; Window size (in K) dw VGABufferSeg ; Start segment of Window A dw VGABufferSeg ; Start segment of Window B dw offset SuperVGABankSwitch dw seg SuperVGABankSwitch BytesPerLine dw 0 ; Bytes per logical scanline XRes dw 0 ; X resolution YRes dw 0 ; Y resolution CWidth db 8 ; Character width CHeight db 8 ; Character height Planes db 0 ; Number of planes BitsPerPixel db 0 ; Bits per pixel Banks db 0 ; Number of banks?? MemMode db 0 ; Memory mode db 0 Pages db 0 ; Number of image pages ModeInfoSize = $-ModeInfo ; Lookup table for filling in the optional mode information in the above ; structure. mode800x600x16 dw 800,600 db 8,8,4,4,1,memPL16 mode1024x768x16 dw 1024,768 db 8,8,4,4,1,memPL16 mode1280x1024x16 dw 1280,1024 db 8,8,4,4,1,memPL16 PartialInfoSize = $-mode1280x1024x16 mode640x350x256 dw 640,350 db 8,8,1,8,1,memPK256 mode640x400x256 dw 640,400 db 8,8,1,8,1,memPK256 mode640x480x256 dw 640,480 db 8,8,1,8,1,memPK256 mode800x600x256 dw 800,600 db 8,8,1,8,1,memPK256 mode1024x768x256 dw 1024,768 db 8,8,1,8,1,memPK256 mode1280x1024x256 dw 1280,1024 db 8,8,1,8,1,memPK256 mode320x200x32k dw 320,200 db 8,8,1,15,1,memPKD mode640x350x32k dw 640,350 db 8,8,1,15,1,memPKD mode640x400x32k dw 640,400 db 8,8,1,15,1,memPKD mode640x480x32k dw 640,480 db 8,8,1,15,1,memPKD mode800x600x32k dw 800,600 db 8,8,1,15,1,memPKD mode1024x768x32k dw 1024,768 db 8,8,1,15,1,memPKD mode1280x1024x32k dw 1280,1024 db 8,8,1,15,1,memPKD mode320x200x16m dw 320,200 db 8,8,1,24,1,memPKD mode640x350x16m dw 640,350 db 8,8,1,24,1,memPKD mode640x400x16m dw 640,400 db 8,8,1,24,1,memPKD mode640x480x16m dw 640,480 db 8,8,1,24,1,memPKD mode800x600x16m dw 800,600 db 8,8,1,24,1,memPKD mode1024x768x16m dw 1024,768 db 8,8,1,24,1,memPKD mode1280x1024x16m dw 1280,1024 db 8,8,1,24,1,memPKD ;---------------------------------------------------------------------------- ; Resident Code ;---------------------------------------------------------------------------- ASSUME cs:uvesa_TEXT, ds:NOTHING, es:NOTHING INCLUDE "SV_PORTS.ASM" INCLUDE "SV_BANKS.ASM" INCLUDE "SV_MODES.ASM" INCLUDE "SV_PAGE.ASM" INCLUDE "SV_MAXPG.ASM" ;---------------------------------------------------------------------------- ; Int10ISR - Video BIOS hook. ;---------------------------------------------------------------------------- ; ; This routine is called whenever an application program makes a call to ; the Video BIOS routines. We check to see if the calls and VESA functions ; calls, and handle them appropriately, or else we simply pass the call ; to the old Video BIOS handler. ; ;---------------------------------------------------------------------------- PROC Int10ISR far cmp ah,VESA_FUNCTIONS ; Is this a VESA function? je @@VesaFunction ; Yes, so handle it ; Check to see if this is the Set Video Mode function, in which case we ; need to check if we are trying to set a standard VGA video mode. or ah,ah jnz @@ToOldBIOS cmp al,13h ja @@ToOldBIOS ; Attempting to set a standard VGA video mode, so pass this call onto the ; SuperVGASetMode routine. mov bx,ax ; BX := video mode number call SuperVGASetMode ; Set the video mode iret @@ToOldBIOS: jmp [OldInt10] ; Jump to old VIDEO BIOS ; This is a VESA function, so dispatch to the appropriate routine depending ; on the subfunction number. @@VesaFunction: cmp al,MAX_FUNCTION ja @@NotSupported ; VESA Function is not supported cmp al,5 ; Bank Switching call? jne @@NotBankSwitch ; No, handle normally ; The bank switch routine can be called as a far function, so we can't ; handle this routine with a simple lookup table. call far SuperVGABankSwitch iret @@NotBankSwitch: xor ah,ah shl al,1 ; AX := index into table xchg ax,bx mov bx,[DispatchTable + bx] xchg ax,bx mov [Status],FAILURE push ds ; Save value of DS call ax ; Call the appropriate function pop ds ; Restor value of DS mov ax,[Status] ; Return status code iret @@NotSupported: xor al,al ; Function is not supported iret ENDP Int10ISR ;---------------------------------------------------------------------------- ; SuperVGAInfo - Get SuperVGA Information ;---------------------------------------------------------------------------- ; ; Function to return information about the SuperVGA video card. ; ; Entry: ES:DI -> 256byte buffer for SuperVGA information ; ; Exit: AX - VESA status code ; ;---------------------------------------------------------------------------- PROC SuperVGAInfo near pusha ; Save register values push ds ; Save DS cld mov ax,cs mov ds,ax mov si,offset VGAInfo ; DS:SI -> VGAInfo Table mov cx,VGAInfoSize rep movsb ; Copy the data across mov [Status],SUCCESS ; Return status code pop ds ; Restore DS popa ; Restore register values ret ENDP SuperVGAInfo ;---------------------------------------------------------------------------- ; SuperVGAModeInfo - Get SuperVGA Video Mode Information ;---------------------------------------------------------------------------- ; ; Function to return information about a specific VESA SuperVGA video mode. ; ; Entry: CX - SuperVGA video mode ; ES:DI -> 256 byte buffer for mode information ; ; Exit: AX - VESA status code ; ;---------------------------------------------------------------------------- PROC SuperVGAModeInfo near pusha ; Save register values call VESAToMGLMode ; AX := MGL mode number cmp ax,-1 je @@Invalid ; Mode is invalid to us! push [BytesPerLine] ; Save current bytes per line value push ax ; Save MGL mode number xor ebx,ebx mov bx,[CntMemory] shl ebx,10 ; EBX := memory in bytes call numPages ; Compute number of video pages mov [Pages],al ; Store number of video pages mov [BytesPerLine],cx ; Stote bytes per line value ; Copy the information specific to the video mode pop ax ; AX := MGL mode number sub ax,grSVGA_800x600x16 mov cx,PartialInfoSize mul cl mov si,offset mode800x600x16 add si,ax push es ; Save ES:DI push di mov ax,cs mov ds,ax ; DS:SI -> correct mode info mov es,ax mov di,offset XRes ; ES:DI -> mode specific info cld rep movsb ; Copy the data across pop di ; Restore ES:DI pop es ; Copy the mode information across mov si,offset ModeInfo ; DS:SI -> VGAInfo Table mov cx,ModeInfoSize rep movsb ; Copy the data across pop [BytesPerLine] ; Restore bytes per line value mov [Status],SUCCESS popa ret ; The video mode is invalid, but the underlying video BIOS may be VESA ; compatible, and the mode number may mean something to it, so we pass it ; on to it. @@Invalid: popa mov ax,4F01h pushf call [OldInt10] ; Call the old BIOS mov [Status],ax ; Save the status of the call ret ENDP SuperVGAModeInfo ;---------------------------------------------------------------------------- ; SuperVGASetMode - Set SuperVGA Video Mode ;---------------------------------------------------------------------------- ; ; Function to set a specific VESA SuperVGA video mode. Only graphics modes ; are supported by this TSR. ; ; Entry: BX - VESA video mode number (bit 15 means don't clear mem). ; ; Exit: AX - VESA status code. ; ;---------------------------------------------------------------------------- PROC SuperVGASetMode near pusha ; Save register values push es mov cx,bx and cl,07Fh cmp cx,13h ja @@VesaMode ; Attempting to set a standard VGA video mode, so convert the mode number ; into an MGL video mode number and skip the stuff below to set a ; VESA video mode. push cx push bx push cs pop es mov di,offset VGAModes ; ES:DI -> list of VGA video modes mov ax,cx mov cx,12 repne scasw ; Search for entry inc cx shr cx,1 sub cx,6 neg cx ; CX := MGL mode number mov [CntMode],cx pop ax pushf call [OldInt10] ; Set the video mode pop cx jmp @@StandardVGAMode @@VesaMode: push bx ; Save VESA mode number for later mov cx,bx and ch,07Fh ; Clear memory clear bit push cx call VESAToMGLMode ; AX := internal MGL video mode cmp ax,-1 jne @@1 pop bx pop bx jmp @@InvalidMode ; Video mode is invalid to us! @@1: mov [CntMode],ax ; Save internal MGL video mode mov bx,ax ; BX := current video mode mov ax,[CntDriver] ; AX := current video driver call loadSVGAMode ; AX,BX := correct value for Int 10h pop cx ; CX := VESA mode number and ch,80h ; isolate clear memory bit jz @@SetMode ; Bit is not set, so simply set the mode ; Request was made to _not_ clear the video memory, so attempt to set the ; correct bit for the OEM video modes. or bx,bx ; BX := 0, so AX := video mode number jz @@SetAX or bh,bh jz @@SetBL or bh,80h ; Set the memory clear bit jmp @@SetMode @@SetAX: or al,80h ; Set the memory clear bit jmp @@SetMode @@SetBL: or bl,80h ; Set the memory clear bit @@SetMode: pushf call [OldInt10] ; Set the video mode pop cx ; CX := VESA mode number mov ax,40h mov es,ax cmp [BYTE es:49h],3 ; Mode is still text mode, did not set jbe @@ModeSetFailed @@StandardVGAMode: mov [CntVESAMode],cx ; Save VESA mode now set call SetupBanks call [InitSVGA] ; Initialise bank switching on SuperVGA's call SetupPaging mov ax,[CntMode] ; AX := current video mode number mov ebx,4096 shl 10 ; Compute with maximum video memory call numPages ; Compute bytes per line value mov [BytesPerLine],cx ; Save BytesPerLine value ; Determine the color resolution of the video mode and save for later mov ax,[CntMode] ; AX := current MGL video mode cmp ax,grVGA_320x200x256 je @@Colors256 cmp ax,grSVGA_1280x1024x16 jbe @@Colors16 cmp ax,grSVGA_1280x1024x256 jbe @@Colors256 cmp ax,grSVGA_1280x1024x32k jbe @@Colors32k mov [CntColors],gr16mColor jmp @@Done @@Colors16: mov [CntColors],gr16Color jmp @@Done @@Colors256: mov [CntColors],gr256Color jmp @@Done @@Colors32k: mov [CntColors],gr32kColor @@Done: mov [CntStartX],0 mov [CntStartY],0 mov [Status],SUCCESS @@ModeSetFailed: pop es popa ret ; The mode number was invalid to us, but may make sense to an underlying ; VESA compatible BIOS. @@InvalidMode: pop es popa mov ax,4F02h pushf call [OldInt10] ; Call the old BIOS mov [Status],ax ; Save the status value mov [CntVESAMode],-1 ; Flag that mode is unknown to us! ret ENDP SuperVGASetMode ;---------------------------------------------------------------------------- ; SuperVGAGetMode - Get Current SuperVGA Video Mode ;---------------------------------------------------------------------------- ; ; Function to return the mode number of the current set video mode. If the ; mode is a normal VGA video mode, the normal mode number is returned, ; otherwise the VESA video mode number for the mode is returned. ; ; Exit: AX - VESA status code ; BX - Current video mode ; ;---------------------------------------------------------------------------- PROC SuperVGAGetMode near push es mov ax,40h mov es,ax xor bx,bx mov bl,[BYTE es:49h] cmp bl,13h mov [Status],SUCCESS jbe @@VGAMode mov bx,[CntVESAMode] ; VESA Video mode is active, so return it cmp bx,-1 jne @@VGAMode ; The mode was not know to us, so it may be an underlying VESA video mode. mov ax,4F03h pushf call [OldInt10] mov [Status],ax @@VGAMode: pop es ret ENDP SuperVGAGetMode ;---------------------------------------------------------------------------- ; SuperVGAVideoState - Save/Restore SuperVGA video state ;---------------------------------------------------------------------------- ; ; Function to save save/restore the SuperVGA video state. This function ; would be very tricky to implement for all supported SuperVGA's if we ; want to save the entire state. In order to do as best as job as possible, ; we save the state of the hardware as much as possible using the normal ; Video BIOS routines, along with the current video BIOS mode number. To ; restore the state we first reset the current video mode, then call the ; BIOS to reset the hardware state, which should work correctly for most ; SuperVGA situations. ; ; Entry: DL - Subfunction number ; 00h - Get state buffer size ; 01h - Save video state ; 02h - Restore video state ; ES:BX -> Video buffer to save state in ; CX - Flags for what to save ; bit 0 - Video hardware state ; bit 1 - Video BIOS state ; bit 2 - Video DAC state ; bit 3 - SuperVGA state ; ; Exit: AH - VESA Status code ; BX - Number of 64 byte blocks needed to save state ; ;---------------------------------------------------------------------------- PROC SuperVGAVideoState near ; First try calling the underlying video BIOS which may be VESA compatible. pusha pushf call [OldInt10] ; Call the old BIOS mov [Status],ax popa cmp [Status],SUCCESS je @@Done ; Succeeded, we are all done! ; Otherwise try to do as much as possible with as little knowledge as ; possible. push dx push cx mov ah,1Ch ; Save/Restore video state BIOS call mov al,dl ; AL := subfunction number pushf call [OldInt10] ; Call the old BIOS pop cx pop dx cmp al,1Ch jne @@Failure test cx,010b jz @@Done cmp dl,2 jne @@Done ; The Video BIOS state was saved, so call the BIOS to set the current ; video mode again, and then restore the video state once more to complete ; things. push cx push dx push es mov ax,40h mov es,ax xor ah,ah mov al,[BYTE es:49h] pushf call [OldInt10] ; Set the old video mode pop es pop dx pop cx mov ah,1Ch mov al,2 pushf call [OldInt10] ; Restore video state again @@Done: mov [Status],SUCCESS @@Failure: ret ENDP SuperVGAVideoState ;---------------------------------------------------------------------------- ; SuperVGABankSwitch - CPU Video Memory Control ;---------------------------------------------------------------------------- ; ; Function to switch video banks for the SuperVGA. This function can be ; called as a far function call, rather than through the Int 10h mechanism ; for speed. ; ; Entry: BH - Subfunction number ; 00h - Select video memory window ; 01h - Get video memory window ; BL - Window number ; 00h - Window A ; 01h - Window B ; DX - Window address in video memory (granularity units) ; ; Exit: AX - VESA status code. ; DX - Window address in video memory (when requested) ; ;---------------------------------------------------------------------------- PROC SuperVGABankSwitch far pusha or bh,bh jnz @@Done ; Simply return the current window mov ax,dx ; AX := bank number or bl,bl jnz @@WindowB call [NewBank] ; Set new read/write bank jmp @@Done @@WindowB: call [ReadBank] ; Set new read bank @@Done: popa mov dx,[CurBank] ; Return the current bank number mov [Status],SUCCESS mov ax,SUCCESS ret ENDP SuperVGABankSwitch ;---------------------------------------------------------------------------- ; SuperVGAScanlineWidth - Get/Set Logical Scanline Length ;---------------------------------------------------------------------------- ; ; Function to get/set the logical scanline length. This value is specified ; in pixels, but may require rounding to the next available value. The ; actual value set will be returned. ; ; Entry: BL - Subfunction number ; 00h - Set scanline length ; 01h - Get scanline length ; CX - Desired scanline length in pixels ; ; Exit: AX - VESA status code ; BX - Bytes per scanline ; CX - Pixels per scanline ; DX - Maximum number of scanlines ; ;---------------------------------------------------------------------------- PROC SuperVGAScanlineLength near pusha mov ax,[CntColors] mov [Status],SUCCESS or bh,bh jnz @@GetScanlineLength ; We are attempting to set the scanline width for the mode. First we need ; to adjust the value into bytes, and then set the CRTC offset register cmp ax,gr16Color je @@Colors16 cmp ax,gr256Color je @@SetOffsetReg cmp ax,gr32kColor je @@Colors32k mov ax,cx shl cx,1 add cx,ax ; CX := bytes per scanline and cx,0FFF8h ; Mask off bottom three bits mov [BytesPerLine],cx ; Save BytesPerLine value shr cx,3 ; Shift value for offset register jmp @@SetOffsetReg @@Colors16: shr cx,3 and cx,0FFF0h ; Mask off bottom four bits mov [BytesPerLine],cx ; Save BytesPerLine value shr cx,4 ; Shift value for offset register jmp @@SetOffsetReg ; CX := bytes per scanline @@Colors256: and cx,0FFF8h ; Mask off bottom three bits mov [BytesPerLine],cx ; Save BytesPerLine value shr cx,3 ; Shift value for offset register jmp @@SetOffsetReg @@Colors32k: shl cx,1 and cx,0FFF8h ; Mask off bottom three bits mov [BytesPerLine],cx ; Save BytesPerLine value shr cx,3 ; Shift value for offset register @@SetOffsetReg: mov dx,CRTC mov ah,cl mov al,13h out dx,ax ; Program the CRTC offset value ; Now return the scanline length @@GetScanlineLength: popa mov bx,[BytesPerLine] ; BX := bytes per scanline cmp ax,gr16Color je @@GetColors16 cmp ax,gr256Color je @@GetColors256 cmp ax,gr32kColor je @@GetColors32k mov ax,cx shr cx,1 sub cx,ax ; CX := pixels per scanline ret @@GetColors16: shl cx,3 ; CX := pixels per scanline ret @@GetColors256: ret @@GetColors32k: shr cx,1 ; CX := pixels per scanline ret ENDP SuperVGAScanlineLength ;---------------------------------------------------------------------------- ; SuperVGADisplayStart - Get/Set Display Start ;---------------------------------------------------------------------------- ; ; Set the display start address for the current SuperVGA video mode. ; ; Entry: BH - 00h ; BL - Subfunction number ; 00h - Set display start ; 01h - Get display start ; CX - Leftmost displayed pixel in scanline ; DX - First displayed scanline ; ; Exit: CX - Leftmost displayed pixel in scanline ; DX - First displayed scanline ; ;---------------------------------------------------------------------------- PROC SuperVGADisplayStart cmp [NewPage],offset NONE_page je @@Failure pusha or bh,bh jnz @@GetDisplayStart ; Set the starting display address. xor eax,eax and edx,0FFFFh ; EDX := first scanline and ecx,0FFFFh ; ECX := leftmost pixel mov ax,[BytesPerLine] mul edx ; EAX := y * bytesPerLine mov bx,[CntColors] cmp bx,gr16Color je @@Colors16 cmp bx,gr256Color je @@Colors256 cmp bx,gr32kColor je @@Colors32k ; Video mode is a 24 bit video mode add eax,ecx ; EAX := x + y * bytesPerLine shl ecx,1 add eax,ecx ; EAX := x * 3 + y * bytesPerLine shr eax,2 ; Adjust to lie on plane boundary jmp @@SetDisplayStart ; Video mode is a 16 color video mode @@Colors16: shr ecx,3 add eax,ecx ; EAX := x/8 + y * bytesPerLine jmp @@SetDisplayStart ; Video mode is a 256 color video mode @@Colors256: add eax,ecx ; EAX := x + y * bytesPerLine shr eax,2 ; Adjust to lie on plane boundary jmp @@SetDisplayStart ; Video mode is a 32k color video mode @@Colors32k: shl ecx,1 add eax,ecx ; EAX := x + y * bytesPerLine shr eax,2 ; Adjust to lie on plane boundary @@SetDisplayStart: mov cl,0Ch ; CL := Start Address High register mov ch,ah ; CH := high byte of new address mov bh,al ; BH := low byte of new address mov bl,0Dh ; BL := Start Address Low register shr eax,16 mov si,ax ; SI := Bits 16+ for SuperVGA's call [NewPage] ; Program the start address mov [CntStartX],cx ; Save the display starting coordinates mov [CntStartY],dx mov [Status],SUCCESS popa ret @@GetDisplayStart: popa mov cx,[CntStartX] ; Return saved starting coordinates mov dx,[CntStartY] mov [Status],SUCCESS @@Failure: ret ENDP SuperVGADisplayStart ;---------------------------------------------------------------------------- ; VESAToMGLMode - Converts a VESA mode number to an MGL mode number ;---------------------------------------------------------------------------- ; ; Internal routine to convert a VESA mode number to an MGL mode number. ; MGL Mode numbers are the ones that we use internally, since the code is ; based on that from the MegaGraph graphics library. ; ; Entry: CX - VESA mode number ; ; Exit: AX - MGL mode number (-1 if not found) ; ; Registers: AX,CX ; ;---------------------------------------------------------------------------- PROC VESAToMGLMode near push bx push ds push si push di ; First check to ensure that the VESA mode number is valid for the currently ; installed SuperVGA adapter. push cs pop ds mov si,offset ModeTable ; DS:SI -> Valid VESA mode table @@VESALoop: lodsw ; Load next valid VESA mode number cmp ax,-1 je @@InvalidMode ; Hit the end of the table cmp ax,cx ; Is this the one? je @@ValidMode ; Yes, so mode is valid jmp @@VesaLoop ; No, so keep looking... ; Convert the VESA mode number to the MGL mode number by searching the ; conversion table. @@ValidMode: mov si,offset VesaModes ; DS:SI -> VESA/MGL mode table @@ModeLoop: lodsw ; AX := VESA mode number or ax,ax jz @@InvalidMode ; Exit if mode is invalid mov bx,ax ; BX := VESA mode number lodsw ; AX := MGL mode number cmp bx,cx ; Found the video mode? je @@Exit ; Yes, found the mode... jmp @@ModeLoop @@InvalidMode: mov ax,-1 ; Video mode not found @@Exit: pop di pop si pop ds pop bx ret ENDP VESAToMGLMode EndResident: ; End of resident code ;---------------------------------------------------------------------------- ; Transient Code. ;---------------------------------------------------------------------------- ASSUME cs:uvesa_TEXT, ds:DGROUP, es:NOTHING ;---------------------------------------------------------------------------- ; bool isLoaded(void) ;---------------------------------------------------------------------------- ; Returns true if the Universal VESA TSR is already loaded in memory. ;---------------------------------------------------------------------------- procstart _isLoaded enter 0,0 push ds GetVector 10h ; ES:BX -> Current INT10h vector mov di,bx sub di,offset Int10ISR - offset Signature ; ES:DI -> Signature in loaded TSR push cs pop ds mov si,offset Signature ; DS:SI -> Signature in .COM file mov cx,SigLen ; CX := length of signature string cld mov ax,1 ; Assume already loaded repe cmpsb jcxz @@AlreadyLoaded ; Driver is already loaded! xor ax,ax ; Driver is not loaded @@AlreadyLoaded: pop ds leave ret procend _isLoaded ;---------------------------------------------------------------------------- ; void goTSR(int driver,int chipID,int memory,int dac) ;---------------------------------------------------------------------------- ; ; This routine installs the VESA driver for the specified SuperVGA ; configuration, and exits to the operating system leaving the required ; code resident in memory. ; ; If we are in testing mode, the routine does not go TSR but simply ; calls the 'C' testing routine, unhooks the interrupts and exits. ; ; Registers: all ; ;---------------------------------------------------------------------------- procstart _goTSR ARG driver:WORD, chipID:WORD, memory:WORD, dac:WORD enter 0,0 ; Store the values for the SuperVGA configuration. mov ax,[driver] mov [CntDriver],ax mov ax,[chipID] mov [CntChipID],ax mov ax,[memory] mov [CntMemory],ax mov ax,[dac] mov [CntDac],ax ; Now determine the list of available video modes for this adapter. push [CntMemory] push [CntDriver] call _MGL_availableModes ; Determine available video modes add sp,4 push ds mov ds,dx mov si,ax ; DS:SI -> MGL video mode table push cs pop es mov di,offset ModeTable ; ES:DI -> Video Mode Table mov bx,offset VesaModes ; CS:BX -> All VESA Modes @@ModeLoop: mov cx,[cs:bx] ; CX := VESA Mode Number jcxz @@DoneModes ; Quit when table exhausted mov dx,[cs:bx+2] ; DX := MGL Mode Number add bx,4 ; CS:BX -> next mode in table push si ; Save start of MGL mode table @@FindMode: lodsw ; AX := MGL video mode number cmp ax,-1 je @@NotFound ; Mode was not found cmp ax,dx je @@Found ; Mode number was found jmp @@FindMode ; Continue till mode is found @@Found: mov ax,cx stosw ; Store the appropriate mode number @@NotFound: pop si ; DS:SI -> MGL video mode table jmp @@ModeLoop ; Continue till table exhausted ; Setup the bank switching and page flipping code, and determine if dual ; banking is supported, modifying the video mode information table if ; not. @@DoneModes: mov ax,0FFFFh stosw ; Terminate the mode list pop ds ; Restore DS call SetupBanks ; Setup bank switching call [InitSVGA] ; Initialise SuperVGA code call SetupPaging ; Setup page flipping cmp [TwoBanks],true je @@DualBank mov [WinBAttr],0 ; Remove support for second video bank @@DualBank: call HookVectors ; Hook interrupt vectors ifndef TESTING ; Now setup to go TSR with resident code. mov ah,31h xor al,al mov dx,offset EndResident add dx,PSPSize + 15 ; PSP is always resident!! shr dx,4 int 21h ; Go TSR! else ; Call the C testing routine, unhook vectors and quit. call _testISR ; Call the test routine call UnhookVectors ; Unhook vectors mov ah,04Ch mov al,1 ; Error code of 1 int 21h ; Exit to DOS endif procend _goTSR ;---------------------------------------------------------------------------- ; HookVectors - Hook into the interrupt vectors that we require. ;---------------------------------------------------------------------------- ; ; Saves the value of the old interrupt vectors that we require, and ; install's hooks to our code for the vectors. ; ; Registers: all ; ;---------------------------------------------------------------------------- PROC HookVectors near ; Save old interrupt vectors GetVector 10h mov [cs:OldInt10Off],bx mov [cs:OldInt10Seg],es ; Insert our interrupt vectors into vector table SetVector 10h, Int10ISR ret ENDP HookVectors ;---------------------------------------------------------------------------- ; UnhookVectors - Unhook from all interrupt vectors that we own. ;---------------------------------------------------------------------------- ; ; Restores the interrupt vector table to what it was before we installed ; ourselves. ; ; Registers: all ; ;---------------------------------------------------------------------------- PROC UnhookVectors push ds mov dx,[OldInt10Seg] mov ds,dx mov dx,[OldInt10Off] mov ah,25h mov al,10h int 21h pop ds ret ENDP UnhookVectors endcodeseg uvesa END