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Assembly Source File | 1993-03-19 | 72.8 KB | 2,629 lines

;**************************************************************************** ;* ;* MegaGraph Graphics Library ;* ;* Copyright (C) 1993 Kendall Bennett. ;* All rights reserved. ;* ;* Filename: $RCSfile: detectgr.asm $ ;* Version: $Revision: 1.2 $ ;* ;* Language: 80386 Assembler ;* Environment: IBM PC (MS DOS) ;* ;* Description: This module contains the auto detection routines to detect ;* the presence of all the standard graphics adapters ;* supported by the MegaGraph graphics library. ;* ;* $Id: detectgr.asm 1.2 1993/03/07 04:03:22 kjb Exp $ ;* ;* Revision History: ;* ----------------- ;* ;* $Log: detectgr.asm $ ;* Revision 1.2 1993/03/07 04:03:22 kjb ;* Numerous bug fixes and enhancements. ;* ;* Revision 1.1 1993/03/03 10:45:16 kjb ;* Initial revision ;* ;**************************************************************************** IDEAL JUMPS ; Fix jumps out of range P386 ; Use 80386 instructions INCLUDE "model.mac" ; Memory model macros header detectgr ; Set up memory model ;**************************************************************************** ; ; Equates used by detectgraph routine. ; ;**************************************************************************** CRTC EQU 3D4h ; Port of CRTC registers INCLUDE "MGRAPH.EQU" ; Include equates for Mgraph routines begdataseg detectgr INCLUDE "MGRAPH.VAR" ; Include variable references enddataseg detectgr begcodeseg detectgr ; Start of code segment ;**************************************************************************** ; ; Global variables used by detectgraph routines. ; ;**************************************************************************** SaveDS dw ? ; Place to save the value of DS register VesaBuf db 256 dup (?) ; VESA Video information block VideoChipID dw 0 ; Internal SuperVGA chip ID VideoMem dw 256 ; Size of video memory (kb) VideoModes dw DefModes ; Pointer to list of available SuperVGA PageFlip dw false ; True if page flipping is available ; Video modes. DacType dw grVGADAC ; Video DAC type ForceDAC dw 0 ; Value to force dac with old db 0 ; Scratch place to store values ;**************************************************************************** ; ; Initialised data used by the detectgraph routines. ; ;**************************************************************************** ; Delimited list of video modes for all supported video cards. This list ; may need to be modified depending on display memory restrictions etc. ; ; During chip identification, it may be found that the chipset detected ; does not support all of the specified modes. In this case, the ; unsupported video modes should be set to a zero (use the UnsupportedMode ; routine for this). ; ; HiColor and TrueColor modes should be specified after the particular ; chip in question. If the appropriate DAC is detected, a zero should ; be used to replace the -1 delimiter to add the list of HiColor or ; TrueColor video modes. DefModes: db -1 AheadModes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256,-1 ATIModes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256 ATI32KModes: db -1,grSVGA_640x480x32k,grSVGA_800x600x32k,-1 ChipsModes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256,-1 EverexModes: db grSVGA_800x600x16,grSVGA_1024x768x16,grSVGA_1280x1024x16 db grSVGA_640x350x256,grSVGA_640x400x256 db grSVGA_640x480x256,grSVGA_800x600x256 db grSVGA_1024x768x256 Everex32KModes: db -1,grSVGA_320x200x32k,grSVGA_640x480x32k EverexTCModes: db -1,grSVGA_640x480x16m,-1 GenoaModes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x350x256,grSVGA_640x400x256 db grSVGA_640x480x256,grSVGA_800x600x256,-1 OAKModes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x480x256,grSVGA_800x600x256 db grSVGA_1024x768x256 OAK32KModes: db -1,grSVGA_640x400x32k,grSVGA_640x480x32k,-1 ParadiseModes: db grSVGA_800x600x16,grSVGA_1024x768x16,grSVGA_1280x1024x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256 Parad32KModes: db -1,grSVGA_640x480x32k,grSVGA_800x600x32k,-1 Trident88Modes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x400x256,grSVGA_640x480x256,-1 Trident89Modes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256,-1 Video7Modes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256,-1 ET3000Modes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x350x256,grSVGA_640x480x256 db grSVGA_800x600x256,-1 ET4000Modes: db grSVGA_800x600x16,grSVGA_1024x768x16,grSVGA_1280x1024x16 db grSVGA_640x350x256,grSVGA_640x400x256 db grSVGA_640x480x256,grSVGA_800x600x256 db grSVGA_1024x768x256 ET400032KModes: db -1,grSVGA_320x200x32k,grSVGA_640x350x32k db grSVGA_640x400x32k,grSVGA_640x480x32k,grSVGA_800x600x32k ET4000TCModes: db -1,grSVGA_640x350x16m,grSVGA_640x400x16m db grSVGA_640x480x16m,-1 NCRModes: db grSVGA_800x600x16,grSVGA_1024x768x16,grSVGA_1280x1024x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256 db grSVGA_1280x1024x256 NCR32KModes: db -1,grSVGA_640x480x32k,grSVGA_800x600x32k,-1 S3Modes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x480x256,grSVGA_800x600x256 db grSVGA_1024x768x256 S332KModes: db -1,grSVGA_640x480x32k,-1 S3TCModes: db -1 CirrusModes: db grSVGA_800x600x16,grSVGA_1024x768x16,grSVGA_1280x1024x16 db grSVGA_640x480x256,grSVGA_800x600x256 db grSVGA_1024x768x256 Cirrus32kModes: db -1,grSVGA_640x480x32k,grSVGA_800x600x32k,-1 CirrusTCModes: db -1,grSVGA_320x200x16m,grSVGA_640x480x16m,-1 AcuMosModes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,-1 AL2101Modes: db grSVGA_800x600x16,grSVGA_1024x768x16,grSVGA_1280x1024x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256 db grSVGA_1280x1024x256,-1 MXICModes: db grSVGA_800x600x16,grSVGA_1024x768x16 db grSVGA_640x350x256,grSVGA_640x400x256 db grSVGA_640x480x256,grSVGA_800x600x256 db grSVGA_1024x768x256,-1 P2000Modes: db grSVGA_800x600x16,grSVGA_1024x768x16,grSVGA_1280x1024x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256 db grSVGA_1280x1024x256 P200032KModes: db -1,grSVGA_640x350x32k,grSVGA_640x400x32k db grSVGA_640x480x32k,grSVGA_800x600x32k,-1 RT3106Modes: db grSVGA_800x600x16,grSVGA_1024x768x16,grSVGA_1280x1024x16 db grSVGA_640x400x256,grSVGA_640x480x256 db grSVGA_800x600x256,grSVGA_1024x768x256 db grSVGA_1280x1024x256,-1 VesaModes: db 20 dup (-1) ; Table to translate EGA display types EGADisplays db grEGA,grEGA_640x200x16 ; 0000b,0001b CGA Display db grEGA,grEGA_640x350x16 ; 0010b,0011b EGA Display db grEGAMONO,0 ; 0100b,0101b MDA Display db grEGA,grEGA_640x200x16 ; 0110b,0111b CGA Display db grEGA,grEGA_640x350x16 ; 1000b,1001b EGA Display db grEGAMONO,0 ; 1010b,1011b MDA Display ; Table of possible VESA video mode numbers and display memory required ; rounded up to the nearest half megabyte or megabyte depending on ; resolution. Cards generally have 256k, 512k, 1M, 2M or 4M on board. AllVesaModes: dw 100h, 256, grSVGA_640x400x256 dw 101h, 512, grSVGA_640x480x256 dw 102h, 256, grSVGA_800x600x16 dw 103h, 512, grSVGA_800x600x256 dw 104h, 512, grSVGA_1024x768x16 dw 105h, 1024, grSVGA_1024x768x256 dw 106h, 1024, grSVGA_1280x1024x16 dw 107h, 2048, grSVGA_1280x1024x256 dw 10Dh, 256, grSVGA_320x200x32k dw 10Fh, 256, grSVGA_320x200x16m dw 110h, 1024, grSVGA_640x480x32k dw 112h, 1024, grSVGA_640x480x16m dw 113h, 1024, grSVGA_800x600x32k dw 115h, 2048, grSVGA_800x600x16m dw 116h, 2048, grSVGA_1024x768x32k dw 118h, 4096, grSVGA_1024x768x16m dw 119h, 4096, grSVGA_1280x1024x32k dw 11Bh, 4096, grSVGA_1280x1024x16m dw 0 ;**************************************************************************** ; ; Set of macros to make the following code more readable, but probably ; less efficient. Efficiency here is not a major concern, but correctness ; definately is :-). ; ;**************************************************************************** MACRO check boardName call Find&boardName ; Check for a particular SuperVGA card jc @@FoundOne ENDM ; Macro to add the HiColor video modes for this video card to the mode ; table. MACRO Add32kColor ModeTable local NoHiColor cmp [DacType],grHCDAC jl NoHiColor mov bx,offset ModeTable mov [BYTE cs:bx],0 ; Clear the -1 termination flag NoHiColor: ENDM ; Macro to add the TrueColor video modes for this video card to the mode ; table. MACRO AddTrueColor ModeTable local NoTrueColor cmp [DacType],grTCDAC jl NoTrueColor mov bx,offset ModeTable mov [BYTE cs:bx],0 ; Clear the -1 termination flag NoTrueColor: ENDM MACRO ClearMode Mode, ModeTable mov al,Mode mov bx,offset ModeTable call UnsupportedMode ; Clear the unsupported video mode ENDM INCLUDE "SV_PORTS.ASM" INCLUDE "SV_MAXPG.ASM" ;---------------------------------------------------------------------------- ; void MGL_detectGraph(int far *graphdriver,int far *chipID,int far *memory, ; int far *dac,int far *graphmode); ;---------------------------------------------------------------------------- ; Autodetects the standard graphics adapters supported by the MegaGraph ; graphics library. ;---------------------------------------------------------------------------- procstart _MGL_detectGraph ARG driver:DWORD, chipID:DWORD, memory:DWORD, dac:DWORD, \ mode:DWORD enter 0,0 pusha push ds mov ax,DGROUP ; Save data segment for later use mov [cs:SaveDS],ax lds si,[dac] mov ax,[si] mov [ForceDAC],ax ; Save value of forced dac type lds di,[driver] ; Load the address of driver in DS:DI les si,[mode] ; Load the address of mode in ES:SI push ds mov ds,[cs:SaveDS] ; Address data segment mov [__grResult],grOK pop ds ; Look for the various subsystems using the subroutines in the order of ; highest performance first. Ie: look for PS/2's then EGA, CGA, then ; hercules monochrome. call FindPS2 ; Is an MCGA or VGA out there? jc @@Exit call FindEGA ; Is an EGA out there? jc @@Exit call FindCGA ; Is a CGA out there? jc @@Exit call FindHGC ; Is a Hercules out there? jc @@Exit push ds mov ds,[cs:SaveDS] ; Address data segment mov [__grResult],grNotDetected pop ds @@Exit: lds si,[chipID] ; Load the address of chip ID in DS:SI mov ax,[VideoChipID]; AX := value of internal chip ID mov [si],ax ; Store the chip ID value lds si,[memory] mov ax,[VideoMem] mov [si],ax lds si,[dac] mov ax,[DacType] mov [si],ax ; Store dac type pop ds popa leave ret procend _MGL_detectGraph ;---------------------------------------------------------------------------- ; char far * _getSuperVGAModes(void) ;---------------------------------------------------------------------------- ; Returns the address of the list of available video modes. ;---------------------------------------------------------------------------- procstart __getSuperVGAModes mov dx,seg DefModes mov ax,[WORD VideoModes] ret procend __getSuperVGAModes ;---------------------------------------------------------------------------- ; int _getSuperVGAPages(int mode,int memory,long *pagesize) ;---------------------------------------------------------------------------- ; Returns the number of available video pages for a specific video mode. ; It also returns the size in bytes of each video page (rounded to the ; nearest bank value). ;---------------------------------------------------------------------------- procstart __getSuperVGAPages ARG mode:WORD, memory:WORD, pagesize:DWORD enter 0,0 push di mov ax,[mode] mov cx,ax and ax,7Fh xor ebx,ebx mov bx,[memory] test cx,80h jnz @@ExtendedPageFlip cmp [PageFlip],true je @@ExtendedPageFlip ; Extended page flipping is not available, so calculate pages using only ; 256k of memory. cmp ax,grVGA_320x200x256 jl @@VGAMode mov ax,1 jmp @@Done @@VGAMode: mov bx,256 @@ExtendedPageFlip: shl ebx,10 call numPages les di,[pagesize] mov [es:di],ebx ; Store the page size for later @@Done: pop di leave ret procend __getSuperVGAPages ;**************************************************************************** ; ; Internal routines used by the detectgraph routine. ; ;**************************************************************************** ;---------------------------------------------------------------------------- ; FindPS2 Determine if a PS2 is out there, and get susbsystem types ;---------------------------------------------------------------------------- ; ; Routine calls INT10h function 1Ah to determine the video BIOS ; Display Combination Code (DCC) for each video subsystem. If the ; PS2 BIOS is not out there, then none of the regs are changed. If ; it is out there, then 1Ah comes back in AL. If there is a PS/2 BIOS, we ; only use it to detect the VGA and MCGA adapters. ; ; Entry: DS:DI -> Address of driver variable ; ES:SI -> Address of mode variable ; ; Exit: Carry flag is set if an MCGA,VGA,SVGA was detected ; ; Registers: AX,BX,CX ; ;---------------------------------------------------------------------------- PROC FindPS2 near mov ax,1A00h ; call video BIOS for info int 10h cmp al,1Ah ; Is the BIOS out there (1Ah in AL) clc jne @@Exit ; Determine if VGA,MCGA,SVGA present from BIOS DCC's mov cl,bh ; BL := active subsystem, BH := inactive xor bh,bh ; BX := DCC of active subsystem xor ch,ch ; CX := DCC of inactive subsystem cmp bx,07h ; Active VGA Mono? je @@VGA cmp cx,07h ; Inactive VGA Mono? je @@VGA cmp bx,08h ; Active VGA Color? je @@VGA cmp cx,08h ; Inactive VGA Color? jne @@CheckMCGA @@VGA: mov [WORD DS:DI],grVGA mov [WORD ES:SI],grVGA_640x480x16 push ds mov ds,[cs:SaveDS] ; Address data segment cmp [__ignoreSVGA],1 pop ds je @@SkipSVGA call FindSuperVGA ; Check to see if a SuperVGA is out there @@SkipSVGA: stc ; We at least found a VGA card jmp @@Exit @@CheckMCGA: cmp bx,0Ch ; Active MCGA color? je @@MCGA cmp cx,0Ch ; Inactive MCGA color? clc jne @@Exit @@MCGA: mov [WORD DS:DI],grMCGA mov [WORD DS:SI],grVGA_320x200x256 stc ; Set the carry flag @@Exit: ret ENDP FindPS2 ;---------------------------------------------------------------------------- ; FindEGA Determine if an EGA is out there and get system configuration ;---------------------------------------------------------------------------- ; ; Routine calls INT10h function 12h to get the EGA BIOS to return system ; configuration info. If the EGA BIOS is not there, then the regs return ; unscathed. Specifically, if BH changes, then the EGA is out there. ; ; Entry: DS:DI -> Address of driver variable ; ES:SI -> Address of mode variable ; ; Exit: Carry flag set if an EGA was detected ; ; Registers: AX,BX,CX ; ;---------------------------------------------------------------------------- PROC FindEGA near mov bl,10h ; BL := 10h (return ega info) mov ah,12h ; AH := INT10h function number int 10h ; Call EGA BIOS for info. ; If EGA is present, BL <> 10h and ; CL = EGA switch settings cmp bl,10h clc je @@Exit ; jump if EGA BIOS not present and bl,3 ; Mask out the Video Ram bits push bx ; Save Video Ram bits on stack mov al,cl ; AL := configuration switches xor ah,ah ; AX := configuration switches and al,11111110b ; Mask bit 1 mov bx,offset cs:EGADisplays add bx,ax ; Index into table xor ah,ah mov al,[cs:bx] ; Translate code mov [WORD DS:DI],ax mov al,[cs:bx + 1] mov [WORD ES:SI],ax pop cx ; Restore Video Ram Bits or cx,cx ; 64kb of EGA RAM? stc jne @@Exit ; We are done... inc [WORD DS:DI] ; Convert to EGA64 and EGA64MONO stc @@Exit: ret ENDP FindEGA ;---------------------------------------------------------------------------- ; FindCGA Determine if a CGA adapter is out there and get info ;---------------------------------------------------------------------------- ; ; Routine checks for a CGA by looking for the CGA's 6845 CRTC at I/O port ; 3D4h. ; ; Entry: DS:DI -> Address of driver variable ; ES:SI -> Address of mode variable ; ; Exit: Carry flag set if a CGA was detected ; ; Registers: AX,BX,CX,DX ; ;---------------------------------------------------------------------------- PROC FindCGA near mov dx,3D4h ; DX := CRTC address port call Find6845 jnc @@Exit mov [WORD DS:DI],grCGA mov [WORD ES:SI],0 stc ; Set carry flag @@Exit: ret ENDP FindCGA ;---------------------------------------------------------------------------- ; FindHGC Determine if a Hercules card is out there. ;---------------------------------------------------------------------------- ; ; This is done by looking for the MDA's 6845 CRTC at I/O port 3B4h. If ; a 6845 is found, the subroutine distinguishes between an MDA and a ; Hercules adapter by monitoring bit 7 of the CRT Staus byte. This bit ; changes on Hercules adapters but does not change on an MDA. ; ; Entry: DS:DI -> Address of driver variable ; ES:SI -> Address of mode variable ; ; Exit: Carry flag set if an HGC was detected ; ; Registers: AX,BX,CX,DX ; ;---------------------------------------------------------------------------- PROC FindHGC near mov dx,3B4h ; DX := CRTC address port call Find6845 jnc @@Exit ; jump if not present mov dx,3BAh ; DX := 3BAh (Status port) in al,dx and al,80h mov ah,al ; AH := bit 7 (Vertical sync on HGC) mov cx,8000h ; do this 32768 times @@WaitForChange: in al,dx and al,80h ; isolate bit 7 cmp ah,al loope @@WaitForChange ; wait for bit 7 to change clc je @@Exit ; if bit 7 didn't change, it's an MDA mov [WORD DS:DI],grHERCMONO mov [WORD ES:SI],0 stc @@Exit: ret ENDP FindHGC ;---------------------------------------------------------------------------- ; FindDAC Routine to detect the presence of HiColor and TrueColor DAC's ;---------------------------------------------------------------------------- ; ; This routine attempts to determine the type of RAM dac installed in the ; video card. This can be used by the following detection routines to ; determine if HiColor or TrueColor video mode support should be included ; in the video mode tables. ; ; Exit: DacType updated with Video DAC type ; ; Registers: AX,BX,CX,DX ; ;---------------------------------------------------------------------------- PROC FindDAC push si push di ; Test for the SS24 TrueColor DAC first. DacToPel in al,dx ; Wait for the same value twice @@L1: mov bl,al in al,dx cmp al,bl jne @@L1 DacToCommand cmp al,8Eh je @@HaveSS24 ; We have an SS24 TrueColor DAC mov cx,8 @@L2: in al,dx cmp al,8Eh je @@HaveSS24 ; Found an SS24 TrueColor DAC loop @@L2 ; Save the state of the command and PEL registers DacToCommand in al,dx mov si,ax ; SI := Old value of command register DacToPel in al,dx mov di,ax ; DI := Old value of PEL register mov ax,si xor al,0FFh ; AL := old command reg XOR FFh mov bl,al ; Save value in BL out dx,al ; Write value to PEL register DacToCommand in al,dx ; Read value of command register cmp al,bl ; If value are the same, Normal DAC je @@NormalDAC ; Normal DAC, so reset PEL reg and exit ; We have a HiColor or TrueColor DAC of some type, so figure out what ; sort it is. DacToCommand mov ax,si xor al,60h ; AL := Old command reg XOR 60h mov bl,al ; Save value in BL out dx,al ; Write to command register DacToCommand in al,dx and al,0E0h and bl,0E0h cmp al,bl jne @@HaveHiColor ; Found an SC11486 HiColor DAC in al,dx mov bl,al DacToPel in al,dx cmp al,bl je @@HaveTrueColor ; Must be an ATT 20c491/2 or some other DAC ; Fall through for Sierra 32k/64k DAC's @@HaveHiColor: mov ax,grHCDAC ; DAC is HiColor mov [DacType],ax jmp @@ResetCommand @@HaveTrueColor: mov ax,grTCDAC ; DAC is TrueColor mov [DacType],ax @@ResetCommand: DacToCommand mov ax,si ; AL := Old value of command register out dx,al @@NormalDAC: DacToPel mov ax,di ; AL := Old value of PEL register out dx,al ; Reset to old value jmp @@Exit @@HaveSS24: mov ax,grTCDAC ; SS24 is TrueColor DAC mov [DacType],ax jmp @@Exit @@Exit: mov ax,[ForceDAC] ; Get value of forced DAC or ax,ax ; Negative if we dont want to force js @@1 mov [DacType],ax ; Force the dac type @@1: pop si pop di ret ENDP FindDAC ;---------------------------------------------------------------------------- ; FindSuperVGA Determine if a SuperVGA is out there, and get information ;---------------------------------------------------------------------------- ; ; Routine performs a number of SuperVGA detection routines to determine ; if a SuperVGA video card is out there. If one is found, we set the driver ; variable to reflect this and exit. Note that we also detect how much ; memory is present on the card and what video modes are available. ; ; This code first appeared in John Bridges VGAKIT library, however it has ; been factorised into a number of independant functions to detect each ; video card. ; ; Entry: DS:DI -> Address of driver variable ; ; Exit: Carry flag is set if a SuperVGA was detected ; ; Registers: AX,BX,CX,DX ; ;---------------------------------------------------------------------------- PROC FindSuperVGA near push ds push es push si push di call FindDAC ; Detect the Video DAC installed mov [PageFlip],false ; Default to no page flipping push ds mov ds,[cs:SaveDS] ; Address data segment cmp [__VESAFirst],1 ; Check _VESAFirst flag pop ds jne @@SkipVESA check VESA @@SkipVESA: check Chips check Paradise check Video7 check Genoa check Everex check Trident check ATI check Ahead check NCR check S3 check AL2101 check MXIC check Cirrus check AcuMos check Tseng check RT3106 check P2000 check Oaktech check VESA pop di pop si pop es pop ds clc ret @@FoundOne: pop di pop si pop es pop ds mov [WORD ds:di],ax ; Store the SuperVGA card identifier stc ret ENDP FindSuperVGA ;---------------------------------------------------------------------------- ; UnsupportedMode Flags a video mode as unsupported for this card ;---------------------------------------------------------------------------- ; ; Flags a video mode as unsupported for this video card, by writing a ; zero into the position where the mode is located. ; ; Entry: AL - Number of unsupported mode ; BX - Offset of video mode table ; ; Exit: BX - Offset of video mode table ; ; Registers: AX,BX ; ;---------------------------------------------------------------------------- PROC UnsupportedMode ; Find the index of the video mode push bx @@Loop: mov ah,[BYTE cs:bx] cmp ah,al ; Found the video mode? je @@FoundIt cmp ah,-1 je @@Exit inc bx jmp @@Loop @@FoundIt: mov [BYTE cs:bx],0 @@Exit: pop bx ret ENDP UnsupportedMode ;---------------------------------------------------------------------------- ; FindVESA Detect the presence of VESA Compatible SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; ;---------------------------------------------------------------------------- PROC FindVESA near ; Check to see if a VESA extended video BIOS is out there. If it is, ; we have a Super VGA card. mov ax,seg VesaBuf mov es,ax mov di,offset VesaBuf mov ax,04F00h int 10h ; Call the VESA video BIOS cmp ax,004Fh jne @@NoVESA cmp [WORD es:di],'EV' jne @@NoVESA cmp [WORD es:di+2],'AS' jne @@NoVESA ; We have a VESA compatible SuperVGA, so determine how much memory must ; be on the video board by finding the amount of memory used by the ; highest resolution video mode supported. ; ; At the same time initialise the table of valid video modes for this ; SuperVGA, and bytes per line values for the video mode. push ds push bp mov ax,[WORD es:di+16] mov ds,ax mov bp,[WORD es:di+14] ; DS:BP -> List of valid VESA modes mov si,offset AllVesaModes mov bx,offset VesaModes cld @@VesaMemLoop: lods [WORD cs:si] ; Load VESA mode number mov cx,ax jcxz @@EndVESA ; Finished when mode number is zero lods [WORD cs:si] ; Load amount of memory required for mode push ax ; and save on stack lods [WORD cs:si] ; Load MGL video mode number push ax ; and save on stack ; First check to see if the mode is a valid VESA mode. mov di,bp ; DS:DI -> mode list @@CheckMode: mov ax,[WORD ds:di] inc di inc di cmp ax,-1 je @@NotFound cmp ax,cx je @@FoundMode ; Yes mode was found jmp @@CheckMode ; Loop for all valid modes @@NotFound: pop ax ; Restore stack pop ax jmp @@VesaMemLoop ; Continue loop @@FoundMode: mov ax,seg VesaBuf mov es,ax mov di,offset VesaBuf mov ax,4F01h ; AX := Query Mode Information int 10h pop dx ; DX := MGL Mode Number pop cx ; CX := Video memory required or ah,ah jnz @@VesaMemLoop ; Mode not supported, try next one test [BYTE es:di],1 jz @@VesaMemLoop ; Mode not supported, try next one ; Video mode is supported, so add to mode table. push bx mov bx,[WORD es:di+16] mov ax,dx call setBytesPerLine ; Set the bytes per line value for mode pop bx mov [BYTE cs:bx],dl ; Store the mode number inc bx cmp cx,[WORD VideoMem] jle @@VesaMemLoop ; Memory is less, try next mode mov [WORD VideoMem],cx ; Increase the memory size jmp @@VesaMemLoop @@EndVESA: pop bp pop ds call checkVESAPageFlip ; Does VESA support page flipping? jc @@NoFlip mov [PageFlip],true @@NoFlip: mov [WORD VideoModes],offset VesaModes mov ax,grSVGA stc ret @@NoVESA: clc ret ENDP FindVESA ;---------------------------------------------------------------------------- ; FindS3 Detect the presence of an S3 based SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindS3 near wrinx CRTC, 38h, 0 ; Lock S3 extended registers tstinx CRTC, 35h, 0Fh ; Check for locked S3 bank switch register jz @@NoS3 ; Bank reg was writeable, not an S3 wrinx CRTC, 38h, 48h ; Unlock S3 extended registers tstinx CRTC, 35h, 0Fh ; Check for unlocked S3 bank switch register jnz @@NoS3 ; Test failed, not an S3 ; Determine the chip ID for the video card and save it for later rdinx CRTC, 30h ; Read chip ID register mov bx,grS3_928 cmp al,90h je @@FindMem ; We have an 86c928 chip mov bx,grS3_801_805 cmp al,0A0h je @@FindMem ; We have an 86c801/86c805 chip mov bx,grS3_924 cmp al,82h je @@FindMem ; We have an 86c924 chip mov bx,grS3_911 ; Fall through for the 86c911 chip ; Determine how much video RAM is on the card @@FindMem: mov [VideoChipID],bx; Save the chip ID rdinx CRTC, 36h ; Read configuration register 1 and al,11100000b ; Mask out bits 7-5 cmp bx,grS3_924 jle @@Mem911 ; We have an 86c801/805/928 based S3. mov [WORD VideoMem],512 cmp al,11100000b je @@DoneMem ; Card has 512k on board mov [WORD VideoMem],1024 cmp al,11000000b je @@DoneMem ; Card has 1Mb on board mov [WORD VideoMem],2048 cmp al,10000000b je @@DoneMem ; Card has 2Mb on board mov [WORD VideoMem],3072 cmp al,01000000b je @@DoneMem ; Card has 3Mb on board mov [WORD VideoMem],4096 jmp @@DoneMem ; Card has 4Mb on board ; We have an 86c911/924. @@Mem911: mov [WORD VideoMem],512 test al,100000b ; Bit 5 is set for 512k jnz @@DoneMem mov [WORD VideoMem],1024 @@DoneMem: wrinx CRTC, 38h, 0 ; Lock S3 extended registers call ModifyS3BytesPerLine mov [PageFlip],true ; Card supports extended page flipping Add32kColor S332KModes AddTrueColor S3TCModes mov [WORD VideoModes],offset S3Modes mov ax,grSVGA_S3 stc ret @@NoS3: clc ret ENDP FindS3 ;---------------------------------------------------------------------------- ; FindATI Detect the presence of an ATI Technologies SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindATI near mov ax,0C000h mov es,ax cmp [WORD es:40h],'13' ; ATI Signature for VGA cards jne @@NoATI ; Check for the ATI product code string '761295520' cmp [WORD es:31h],'67' jne @@NoATI cmp [WORD es:31h+2],'21' jne @@NoATI cmp [WORD es:31h+4],'59' jne @@NoATI cmp [WORD es:31h+6],'25' jne @@NoATI cmp [BYTE es:31h+8],'0' jne @@NoATI mov dx,1CEh ; DX := port of ATI extended registers mov bl,[BYTE es:43h] ; BL := ATI Chip Version cmp bl,'3' jae @@Ver6up ; Check for memory on later chip versions mov [VideoChipID],grATI_18800_1 cmp bl,'1' jne @@Not18800 ; Remove unsupported video modes for (18800 chip) mov [VideoChipID],grATI_18800 ClearMode grSVGA_1024x768x16, ATIModes ; Determine the memory size on chip versions 3-4 (18800, 18800-1) @@Not18800: rdinx 1CEh, 0BBh ; Get RamSize bits and al,20h jz @@DoneATI mov [WORD VideoMem],512 ; Card has 512kb of memory jmp @@DoneATI ; Determine memory size on chip versions 6+ (28800-2, 28800-4, 28800-5) @@Ver6up: mov [VideoChipID],grATI_28800_2 rdinx 1CEh, 0B0h ; Get RamSize bits test al,10h ; Check if RamSize is 256k or 512k jz @@Ver7Check mov [WORD VideoMem],512 ; Card has at least 512k of memory @@Ver7Check: cmp bl,'4' jb @@DoneATI ; Done for version 6 chips mov [VideoChipID],grATI_28800_4 cmp bl,'5' jb @@Not28800_5 mov [VideoChipID],grATI_28800_5 @@Not28800_5: test al,8 ; Check version 7+ chip memory size jz @@DoneATI mov [WORD VideoMem],1024; Card has 1024k of memory @@DoneATI: mov [DacType],grVGADAC ; Default to normal DAC test [BYTE es:44h],8 ; Check bit 7 for HiColor DAC jz @@NoHiColor mov [DacType],grHCDAC ; We have a 15 bit HiColor DAC Add32kColor ATI32KModes @@NoHiColor: mov [PageFlip],true ; Card supports extended page flipping mov [WORD VideoModes],offset ATIModes mov ax,grSVGA_ATI stc ret @@NoATI: clc ret ENDP FindATI ;---------------------------------------------------------------------------- ; FindNCR Detect the presence of the NCR 77C22E SuperVGA boards ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindNCR near tstinx 3C4h, 5, 5 ; Test for extended register enable chip jnz @@NoNCR ; Check failed, so not an NCR wrinx 3C4h, 5, 0 ; Disable extended registers tstinx 3C4h, 10h, 0FFh ; Test Cursor location y register jz @@NoNCR ; Reg was writeable, so test failed wrinx 3C4h, 5, 1 ; Enable extended registers tstinx 3C4h, 10h, 0FFh ; Test Cursor location y register jnz @@NoNCR ; Reg was not writeable, so not NCR ; Determine the chip revision rdinx 3C4h, 8 ; Get chip version number shr al,4 cmp al,2 jae @@NCR77C22E ; We have an NCR77C20/21 chip. These do not support certain modes. ClearMode grSVGA_1280x1024x16, NCRModes ClearMode grSVGA_1024x768x256, NCRModes ClearMode grSVGA_1280x1024x256, NCRModes @@NCR77C22E: mov ax,4096 ; Maximum of 4Mb memory mov bx,offset NCRSwitch ; Offset of bank switch routine mov cx,5Eh ; Values to set 640x400x256 xor dx,dx call CheckMem ; Manually check amount of memory mov [PageFlip],true ; Card supports extended page flipping Add32kColor NCR32KModes mov [WORD VideoModes],offset NCRModes mov ax,grSVGA_NCR stc ret @@NoNCR: clc ret ENDP FindNCR ;---------------------------------------------------------------------------- ; FindTrident Detect the presence of the Trident SuperVGA boards ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindTrident near ; When we force the old defintions on Trident TVGA's, they tend to hang up ; if you do it with a 16 bit port instruction. Doing it with 8 bit ; instructions fixes the problem (seems to happen on older cards). ; ; Note that the test in VGADOC that writes stuff to the bank switch ; registers causes some TVGA's to hang up severly (the one I tested it on ; it did). Seems that if you reset the card by setting a video mode before ; doing any bank switching, the problem goes away, but if you dont do this, ; the machine goes off into the never never ... mov dx,3C4h mov al,0Bh out dx,al inc dl xor al,al out dx,al ; Force old definitions in al,dx ; Force new definitions and al,0Fh cmp al,2 jb @@NoTrident ; Trident 8800BR only has 128k banks cmp al,2 je @@Trident88 ; We have a Trident 8800CS ; Must be a Trident 8900, 8900C or 9000 rdinx CRTC, 1Fh ; Read memory size register and al,3 cmp al,1 jb @@LowMem mov [WORD VideoMem],512 ; Card has 512kb of memory cmp al,3 jb @@LowMem mov [WORD VideoMem],1024 ; Card has 1Mb of memory @@LowMem: mov [PageFlip],true ; Card supports extended page flipping mov [WORD VideoModes],offset Trident89Modes mov ax,grSVGA_TRIDENT89 stc ret @@Trident88: rdinx CRTC, 1Fh ; Read memory size register and al,2 jz @@LowMem88 mov [WORD VideoMem],512 ; Card has 512kb of memory @@LowMem88: mov [PageFlip],true ; Card supports extended page flipping mov [WORD VideoModes],offset Trident88Modes mov ax,grSVGA_TRIDENT88 stc ret @@NoTrident: clc ret ENDP FindTrident ;---------------------------------------------------------------------------- ; FindVideo7 Detect the presence of a Video7 SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindVideo7 near mov ax,6F00h xor bx,bx int 10h cmp bx,'V7' jnz @@NoVideo7 mov ax,6F07h ; Determine how much memory is present int 10h and ah,7Fh cmp ah,2 jb @@1 mov [WORD VideoMem],512 ; Card has 512kb of memory @@1: cmp ah,4 jb @@2 mov [WORD VideoMem],1024 @@2: mov [WORD VideoModes],offset Video7Modes mov [PageFlip],true ; Card supports extended page flipping mov ax,grSVGA_VIDEO7 stc ret @@NoVideo7: clc ret ENDP FindVideo7 ;---------------------------------------------------------------------------- ; FindGenoa Detect the presence of a Genoa GVGA SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindGenoa near mov ax,0C000h mov es,ax mov bx,[es:37h] ; Get offset of information table cmp [BYTE es:bx],77h jne @@NoGenoa cmp [WORD es:bx+2],6699h jne @@NoGenoa mov al,[BYTE es:bx+1] ; Get card version number or al,al jz @@HaveGenoa256 ; Found a Genoa 62/300 cmp al,11h je @@HaveGenoa512 ; Found a Genoa 64/600 cmp al,22h je @@HaveGenoa256 ; Found a Genoa 6100 jmp @@NoGenoa ; Other Genoa's have Tseng chips @@HaveGenoa512: mov [WORD VideoMem],512 @@HaveGenoa256: mov [WORD VideoModes],offset GenoaModes mov ax,grSVGA_GENOA stc ret @@NoGenoa: clc ret ENDP FindGenoa ;---------------------------------------------------------------------------- ; FindParadise Detect the presence of a Paradise SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindParadise near rdinx 3CEh, 0Fh ; Read old register value mov [old],al ; Save old value modinx 3CEh, 0Fh, 17h, 0 ; Lock paradise registers tstinx 3CEh, 9, 7Fh ; Test if bank register is there jz @@NoParadise ; Register wrote, so not paradise wrinx 3CEh, 0Fh, 5 ; Unlock paradise registers tstinx 3CEh, 9, 7Fh ; Test if bank register is there jnz @@NoParadise ; Register wouldn't write, not paradise ; We have a Paradise SuperVGA, so determine what chip it is. rdinx CRTC, 29h ; Read value of WD90Cxx register lock mov [old],al ; Save old value modinx CRTC, 29h, 8Fh, 85h ; Unlock WD90Cxx registers tstinx CRTC, 2Bh, 0FFh ; Test WD90Cxx scratch register jnz @@HavePVGA ; We have a PVGA1 rdinx 3C4h, 6 ; Read value of WD90C1x register mov [old],al ; Save old value wrinx 3C4h, 6, 48h tstinx 3C4h, 7, 0F0h jnz @@HaveWD90C00 tstinx 3C4h, 10h, 0FFh jnz @@HavePVGA ; WD90C2x has same modes as PVGA tstinx 3C4h, 14h, 0Fh jnz @@HaveWD90C1x rdinx CRTC, 37h cmp al,31h mov [VideoChipID],grPARA_90c31 je @@MemCheck ; Have a WD90C31 ; Chip is a WD90C30. mov [VideoChipID],grPARA_90c30 wrinx 3C4h, 6, [old] ; Restore register value ClearMode grSVGA_1280x1024x16, ParadiseModes jmp @@MemCheck @@HaveWD90C1x: wrinx 3C4h, 6, [old] ; Restore register value ClearMode grSVGA_1280x1024x16, ParadiseModes ClearMode grSVGA_1024x768x256, ParadiseModes mov [VideoChipID],grPARA_90c10 tstinx 3C4h, 0Ah, 04h jnz @@MemCheck mov [VideoChipID],grPARA_90c11 jmp @@MemCheck @@HaveWD90C00: mov [VideoChipID],grPARA_90c00 wrinx 3C4h, 6, [old] ; Restore register value ClearMode grSVGA_1280x1024x16, ParadiseModes ClearMode grSVGA_1024x768x256, ParadiseModes jmp @@MemCheck @@HavePVGA: mov [VideoChipID],grPARA_PVGA1A wrinx CRTC, 29h, [old] ; Restore value of WD90Cxx register lock ClearMode grSVGA_1024x768x16, ParadiseModes ClearMode grSVGA_1280x1024x16, ParadiseModes ClearMode grSVGA_800x600x256, ParadiseModes ClearMode grSVGA_1024x768x256, ParadiseModes jmp @@MemCheck @@MemCheck: rdinx 3CEh, 0Bh ; Read memory size register shr al,6 cmp al,2 jb @@DoneMem mov [WORD VideoMem],512 ; Card has 512kb of memory cmp al,3 jb @@DoneMem mov [WORD VideoMem],1024; Card has 1024kb of memory @@DoneMem: mov [PageFlip],true ; Card supports extended page flipping Add32kColor Parad32KModes mov [WORD VideoModes],offset ParadiseModes ; Ok, now check to see if the card is capable of 800x600x16 color mode. If ; it isn't, then the card is probably running on an LCD display, so we ; disable all modes above 640x480. call saveMode mov ax,58h or 80h ; Don't clear the memory! int 10h call CheckGraphics jc @@Have800x600 ClearMode grSVGA_800x600x16, ParadiseModes ClearMode grSVGA_1024x768x16, ParadiseModes ClearMode grSVGA_800x600x256, ParadiseModes ClearMode grSVGA_1024x768x256, ParadiseModes ClearMode grSVGA_800x600x32k, ParadiseModes @@Have800x600: call restoreMode mov ax,grSVGA_PARADISE stc ret @@NoParadise: wrinx 3CEh, 15, [old] ; Restore old register value clc ret ENDP FindParadise ;---------------------------------------------------------------------------- ; FindChips Detect the presence of a Chips & Technologies SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindChips near mov ax,5F00h ; Get controller info servic xor bx,bx int 10h cmp al,5Fh ; AL == 5F we have a Chips jnz @@NoChips ; We have a Chips & Tech SuperVGA, so determine what chipset it is mov [PageFlip],true ; Card supports extended page flipping shr bl,4 cmp bl,0 je @@Have82c451 cmp bl,1 je @@Have82c452 cmp bl,2 je @@Have82c451 ; 82c455 has same modes as 451 cmp bl,4 je @@Have82c451 ; 82c456 has same modes as 451 mov [VideoChipID],grCHIPS_82c453 jmp @@CheckMem ; 82c453+ support all modes @@Have82c451: mov [PageFlip],false ; No page flipping on this chip ClearMode grSVGA_1024x768x16, ChipsModes ClearMode grSVGA_640x480x256, ChipsModes ClearMode grSVGA_800x600x256, ChipsModes ClearMode grSVGA_1024x768x256, ChipsModes mov [VideoChipID],grCHIPS_82c451 jmp @@CheckMem @@Have82c452: ClearMode grSVGA_800x600x256, ChipsModes ClearMode grSVGA_1024x768x256, ChipsModes mov [VideoChipID],grCHIPS_82c452 jmp @@CheckMem ; Determine memory size @@CheckMem: cmp bh,1 jb @@DoneMem mov [WORD VideoMem],512 cmp bh,2 jb @@DoneMem mov [WORD VideoMem],1024 @@DoneMem: mov [WORD VideoModes],offset ChipsModes mov ax,grSVGA_CHIPS stc ret @@NoChips: clc ret ENDP FindChips ;---------------------------------------------------------------------------- ; FindTseng Detect the presence of the ET3000 and ET4000 SuperVGA boards ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindTseng near outp 3BFh, 3 outp 3D8h, 0A0h ; Enable ET4000 extensions tstreg 3CDh, 3Fh ; Test bank switch register jnz @@NoTseng ; Test failed, not a Tseng ; We have a Tseng card, so determine if it is an ET3000 or ET4000 tstinx CRTC, 33h, 0Fh ; Test for ET4000 extended start address jz @@ET4000 ; We have an ET3000 board, so check the amount of memory installed mov ax,512 ; Maximum of 512k on board mov bx,offset ET3000Switch mov cx,2Dh ; Values to set 640x350x256 xor dx,dx call CheckMem mov [PageFlip],true ; Card supports extended page flipping mov [WORD VideoModes],offset ET3000Modes mov ax,grSVGA_ET3000 stc ret ; We have an ET4000 board, so determine the amount of memory installed @@ET4000: rdinx CRTC, 37h ; Read memory size bits and al,0Bh cmp al,0Ah jb @@1 mov [WORD VideoMem],512 @@1: cmp al,0Bh jb @@2 mov [WORD VideoMem],1024 ; If the board has a 32k color DAC on board, check to see if we can set ; the 320x200 32k color mode which is not available on all boards. @@2: mov [VideoChipID],grET4000_MEGAEVA call SaveMode cmp [DacType],grHCDAC jl @@Check1280 mov ax,10F0h mov bx,13h or 80h int 10h cmp ax,0010h je @@CheckTC ClearMode grSVGA_320x200x32k, ET400032KModes+1 ; If the board has a 24 bit video DAC on board, determine what type of ; board it is (MegaEva/2, Speedstar 24, Genoa 7900), which all have ; different video mode numbers. @@CheckTC: cmp [DacType],grTCDAC jne @@Check1280 ; Assume board is a MegaEva/2, unless we find otherwise mov ax,10E0h mov bx,2Eh or 80h int 10h cmp ax,0010h jne @@CheckGenoa ; Not speedstar, check for Genoa 7900 ; Board is a Diamond Speedstar 24 mov [VideoChipID],grET4000_SPEEDSTAR ClearMode grSVGA_640x350x16m, ET4000TCModes+1 ClearMode grSVGA_640x400x16m, ET4000TCModes+1 jmp @@Check1280 @@CheckGenoa: mov ax,10F0h mov bx,3Eh or 80h int 10h cmp ax,0010h jne @@Check1280 ; Not a Genoa, must be MegaEva/2... ; Board is a Genoa 7900 mov [VideoChipID],grET4000_GENOA ClearMode grSVGA_640x350x16m, ET4000TCModes+1 ClearMode grSVGA_640x400x16m, ET4000TCModes+1 ; Check to see if the 1280x1024x16 color video mode is available. @@Check1280: mov ax,03Dh or 80h ; 1280x1024x16 color video mode int 10h call CheckGraphics jc @@DoneCheck ; Yes, mode is available ClearMode grSVGA_1280x1024x16, ET4000Modes @@DoneCheck: call RestoreMode mov [PageFlip],true ; Card supports extended page flipping Add32kColor ET400032KModes AddTrueColor ET4000TCModes mov [WORD VideoModes],offset ET4000Modes mov ax,grSVGA_ET4000 stc ret @@NoTseng: clc ret ENDP FindTseng ;---------------------------------------------------------------------------- ; FindEverex Detect the presence of an Everex SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindEverex near mov ax,7000h xor bx,bx int 10h cmp al,70h jnz @@NoEverex ; Some Everex boards use Trident and ET4000 chipsets. These boards will be ; picked up by the low level INIT_everex routine. We do however determine ; the chipset type here, since all everex boards use the same video ; mode numbers. mov [PageFlip],true ; Default to page flipping shr dx,4 mov [VideoChipID],grEVEREX_Ev236 cmp dx,236h ; UltraGraphics - Trident Chip je @@CheckMem mov [VideoChipID],grEVEREX_Ev620 cmp dx,620h ; Vision VGA - Trident Chip je @@CheckMem mov [VideoChipID],grEVEREX_Ev629 cmp dx,629h ; ViewPoint TC - ET4000 Chip je @@CheckMem mov [VideoChipID],grEVEREX_Ev673 cmp dx,673h ; EVGA - Trident Chip je @@CheckMem mov [VideoChipID],grEVEREX_Ev678 cmp dx,678h ; Viewpoint - Trident Chip je @@CheckMem mov [VideoChipID],grEVEREX_EvNR mov [PageFlip],false ; No page flipping on this card @@CheckMem: shr ch,6 cmp ch,1 jb @@DoneMem mov [WORD VideoMem],512 ; Card has 512kb of memory cmp ch,2 jb @@DoneMem mov [WORD VideoMem],1024 ; Card has 1024kb of memory cmp ch,3 jb @@DoneMem mov [WORD VideoMem],2048 ; Card has 2048kb of memory @@DoneMem: Add32kColor Everex32KModes AddTrueColor EverexTCModes mov [WORD VideoModes],offset EverexModes mov ax,grSVGA_EVEREX stc ret @@NoEverex: clc ret ENDP FindEverex ;---------------------------------------------------------------------------- ; FindAhead Detect the presence of a Ahead A or B SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindAhead near rdinx 3CEh, 0Fh mov [old],al wrinx 3CEh, 0Fh, 0 ; Disable extended registers tstinx 3CEh, 0Dh, 0FFh ; Test for bank switch register jz @@NoAhead ; Register wrote, so not Ahead wrinx 3CEh, 0Fh, 20h ; Enable extended registers tstinx 3CEh, 0Dh, 0FFh ; Test for bank switch register jnz @@NoAhead ; Register didn't write, so not Ahead ; SuperVGA is an Ahead, so determine type. rdinx 3CEh, 0Fh ; Read chip version register and al,0Fh jnz @@AheadB ; We have an Ahead B ClearMode grSVGA_1024x768x256, AheadModes mov ax,512 ; Maximum of 512k on board mov bx,offset AHEADASwitch mov cx,60h ; Values to set 640x400x256 xor dx,dx call CheckMem mov [WORD VideoModes],offset AheadModes mov ax,grSVGA_AHEADA stc ret @@AheadB: mov ax,1024 ; Maximum of 1024k on board mov bx,offset AHEADBSwitch mov cx,60h ; Values to set 640x400x256 xor dx,dx call CheckMem mov [PageFlip],true ; Card supports extended page flipping mov [WORD VideoModes],offset AheadModes mov ax,grSVGA_AHEADB stc ret @@NoAhead: wrinx 3CEh, 0Fh, [old] ; Restore register clc ret ENDP FindAhead ;---------------------------------------------------------------------------- ; FindCirrus Detect the presence of an Cirrus 54xx SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindCirrus near rdinx 3C4h, 6 mov [old],al ; Save of value of register wrinx 3C4h, 6, 12h ; Enable extended registers rdinx 3C4h, 6 cmp al,12h ; Check value in extended register lock jne @@NoCirrus tstinx 3C4h, 1Eh, 3Fh jnz @@NoCirrus ; Reg wasn't writeable, test failed tstinx CRTC, 1Bh, 0FFh jnz @@NoCirrus ; Reg wasn't writeable, test failed ; We have a Cirrus 54xx SuperVGA, so determine how much memory is on board rdinx 3C4h, 0Fh ; Get value of memory size register shr al,3 and al,3 cmp al,1 jb @@DoneCirrus mov [WORD VideoMem],512 cmp al,2 jb @@DoneCirrus mov [WORD VideoMem],1024 cmp al,3 @@DoneCirrus: Add32kColor Cirrus32KModes AddTrueColor CirrusTCModes mov [PageFlip],true ; Card supports page flipping mov [WORD VideoModes],offset CirrusModes mov [VideoChipID],grCIRRUS_5422 mov ax,grSVGA_CIRRUS54 stc ret @@NoCirrus: wrinx 3C4h, 6, [old] ; Restore extended register enable clc ret ENDP FindCirrus ;---------------------------------------------------------------------------- ; FindAcuMos Detect the presence of an AcuMos SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindAcuMos near rdinx 3C4h, 6 mov [old],al ; Save of value of register wrinx 3C4h, 6, 12h ; Enable extended registers tstinx 3CEh, 9, 30h ; Test scratchpad 9 again jnz @@NoAcuMos ; Reg not wasn't writeable, test failed ; We have an AcuMos SuperVGA, so determine how much memory is on board rdinx 3C4h, 0Ah ; Get scratchpad index 10 and al,3 cmp al,1 jb @@DoneAcuMos mov [WORD VideoMem],512 cmp al,2 jb @@DoneAcuMos mov [WORD VideoMem],1024 cmp al,3 jb @@DoneAcuMos mov [WORD VideoMem],2048 @@DoneAcuMos: mov [WORD VideoModes],offset AcuMosModes mov ax,grSVGA_ACUMOS stc ret @@NoAcuMos: wrinx 3C4h, 6, [old] ; Restore extended register enable clc ret ENDP FindAcuMos ;---------------------------------------------------------------------------- ; FindOaktech Detect the presence of an Oak Technologies SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindOaktech near tstinx 3DEh, 0Dh, 38h ; Test for memory size register jnz @@NoOakTech ; Do not have an OakTech board ; We have an Oak Technologies SuperVGA, so determine the type. The OTI-037C ; bank switching registers are read only, so the following test will fail ; for these cards. tstinx 3DEh, 11h, 0FFh ; Look for R/W bank switch register jnz @@Have037C ; Have an OTI-037C ; We have an OAK SuperVGA, so determine what chipset it is rdinx 3DEh, 0Bh ; Read Chip Revision register shr al,5 cmp al,5 mov [VideoChipID],grOAK_077 je @@Have077 ; Chip is an OTI-077 mov [VideoChipID],grOAK_067 ClearMode grSVGA_1024x768x256, OAKModes @@Have077: rdinx 3DEh, 0Dh ; Read memory size register shr al,6 or al,al jz @@DoneMem ; Board has 256k mov [WORD VideoMem],512 cmp al,2 je @@DoneMem mov [WORD VideoMem],1024 jmp @@DoneMem ; We have an OTI-037C SuperVGA. The only supported video mode is 800x600x16 ; with 256k of memory. @@Have037C: mov [VideoChipID],grOAK_037C rdinx 3DEh, 0Dh ; Read memory size register shr al,6 or al,al jz @@DoneMem ; Board has 256k mov [WORD VideoMem],512 @@DoneMem: Add32kColor OAK32KModes mov [WORD VideoModes],offset OAKModes mov ax,grSVGA_OAKTECH stc ret @@NoOaktech: clc ret ENDP FindOaktech ;---------------------------------------------------------------------------- ; FindAL2101 Detect the presence of an Advance Logic 2101 SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindAL2101 near tstreg 8286h, 0FFh ; Check for Start Pixel Low register jnz @@NoAL2101 ; Test failed, no AL2101 tstinx CRTC, 1Fh, 3Bh ; Check for Emulation register jnz @@NoAL2101 ; Test failed, no AL2101 tstinx 3CEh, 0Dh, 0Fh ; Check for Fill Color register jnz @@NoAL2101 ; Test failed, no AL2101 ; We have an AL2101 based SuperVGA rdinx CRTC, 1Eh ; Read memory size register and al,3 cmp al,1 jb @@DoneMem mov [WORD VideoMem],512 cmp al,2 jb @@DoneMem mov [WORD VideoMem],1024 cmp al,3 jb @@DoneMem mov [WORD VideoMem],2048 @@DoneMem: mov [DacType],grHC2DAC ; AL2101 has a 16 bit DAC mov [WORD VideoModes],offset AL2101Modes mov ax,grSVGA_AL2101 stc ret @@NoAL2101: clc ret ENDP FindAL2101 ;---------------------------------------------------------------------------- ; FindMXIC Detect the presence of an MXIC 68010 SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindMXIC near rdinx 3C4h, 0A7h ; Read extend reg enable value mov [old],al wrinx 3C4h, 0A7h, 0 ; Disable extended registers tstinx 3C4h, 0C5h, 0FFh ; Test for bank switch register jz @@NoMXIC ; Test passed, so not MXIC wrinx 3C4h, 0A7h, 87h ; Enable extended registers tstinx 3C4h, 0C5h, 0FFh ; Test for bank switch register jnz @@NoMXIC ; Test failed, so not MXIC ; We have an MXIC SuperVGA. rdinx 3C4h, 0C2h ; Read memory size register shr al,2 and al,3 cmp al,1 jb @@DoneMem mov [WORD VideoMem],512 cmp al,2 jb @@DoneMem mov [WORD VideoMem],1024 @@DoneMem: mov [WORD VideoModes],offset MXICModes mov ax,grSVGA_MXIC stc ret @@NoMXIC: wrinx 3C4h, 0A7h, [old] ; Restore register clc ret ENDP FindMXIC ;---------------------------------------------------------------------------- ; FindP2000 Detect the presence of a Primus 2000 SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindP2000 near tstinx 3CEh, 3Dh, 03Fh ; Check for Status command register jnz @@NoP2000 ; Test failed, not P2000 tstreg 3D6h, 01Fh ; Check for bank switch register jnz @@NoP2000 ; Test failed, not P2000 tstreg 3D7h, 01Fh ; Check for bank switch register jnz @@NoP2000 ; Test failed, not P2000 ; We have a Primus P2000 SuperVGA card. mov ax,2048 ; Maximum of 2048k on board mov bx,offset P2000Switch mov cx,2Ch ; Values to set 640x400x256 xor dx,dx call CheckMem Add32kColor P200032KModes mov [PageFlip],true ; Card supports extended page flipping mov [WORD VideoModes],offset P2000Modes mov ax,grSVGA_P2000 stc ret @@NoP2000: clc ret ENDP FindP2000 ;---------------------------------------------------------------------------- ; FindRT3106 Detect the presence of a RealTek 3106 SuperVGA board ;---------------------------------------------------------------------------- ; ; Routine detects if the SuperVGA boards is present and determines how much ; memory is on it. ; ; Exit: Carry flag is set if board was detected ; ; AX - Video card identifier ; [VideoMem] - Amount of video memory on board ; [VideoChipID] - Chip revision id ; ;---------------------------------------------------------------------------- PROC FindRT3106 near tstinx CRTC, 1Fh, 3h ; Test for scratch register jnz @@NoRT3106 tstreg 3D6h, 0Fh ; Test for bank switch register jnz @@NoRT3106 tstreg 3D7h, 0Fh ; Test for bank switch register jnz @@NoRT3106 ; We have a RealTek 3106 SuperVGA rdinx CRTC, 1Ah ; Get chip version number mov bl,al ; Save chip version number shr bl,6 rdinx CRTC, 1Eh ; Get memory size register and al,15 cmp al,1 jb @@DoneMem mov [WORD VideoMem],512 cmp al,2 jb @@DoneMem or bl,bl jz @@Version0 mov [WORD VideoMem],1024 cmp al,3 jb @@DoneMem mov [WORD VideoMem],2048 jmp @@DoneMem @@Version0: cmp al,3 jb @@DoneMem mov [WORD VideoMem],1024 @@DoneMem: mov [WORD VideoModes],offset RT3106Modes mov ax,grSVGA_RT3106 stc ret @@NoRT3106: clc ret ENDP FindRT3106 OldBIOSMode db ? ; Old BIOS mode Old50Lines db ? Oldx db ? ; Old cursor position Oldy db ? ;---------------------------------------------------------------------------- ; SaveMode - Saves the current video BIOS mode, for later restoration ;---------------------------------------------------------------------------- ; ; Registers: none. ; ;---------------------------------------------------------------------------- PROC SaveMode pusha ; Find the current video mode so that we can restore it easily mov ah,0Fh ; Get current video mode service int 10h mov [OldBIOSMode],al ; Save old video mode mov ah,03h ; Get cursor position int 10h mov [Oldx],dl mov [Oldy],dh mov [Old50Lines],0 ; Default to non-50 line mode mov ax,1130h ; AH := INT 10h function number ; AL := Get character gen information mov bh,00 ; Get contents of INT 1Fh xor dl,dl ; Clear dl int 10h ; Determine number of lines (in dl) cmp dl,49 ; 50 line mode? jne @@Done ; No, must have been 25 lines mov [Old50Lines],1 ; Yes, 50 line mode was on @@Done: popa ret ENDP SaveMode ;---------------------------------------------------------------------------- ; RestoreMode - Restores the VIDEO BIOS mode previously saved. ;---------------------------------------------------------------------------- ; ; Registers: none. ; ;---------------------------------------------------------------------------- PROC RestoreMode pusha mov ah,0 ; Set video mode service mov al,[OldBIOSMode] ; Get old BIOS mode number or al,80h ; Set the don't clear memory bit int 10h ; Set the video mode cmp [Old50Lines],0 ; Was 50 line mode set? je @@Exit ; No, don't set it up mov ax,1112h ; AH := INT 10h function number ; AL := 8x8 character set load mov bl,0 ; BL := block to load int 10h ; load 8x8 characters into RAM @@Exit: mov ah,02h mov dl,[Oldx] mov dh,[Oldy] xor bh,bh int 10h ; Set cursor location popa ret ENDP RestoreMode ;---------------------------------------------------------------------------- ; CheckGraphics - Check to see if graphics mode is currently active. ;---------------------------------------------------------------------------- ; ; This routine checks to see if a graphics mode was successfully set, ; setting the carry flag if it was. ; ; Exit: carry - Set if graphics mode is set. ; ; Registers: None. ; ;---------------------------------------------------------------------------- PROC CheckGraphics push ax mov ax,40h mov es,ax xor ax,ax cmp [BYTE es:49h],3 ; Mode is still text mode, did not set ja @@IsGraphics pop ax clc ret @@IsGraphics: pop ax stc ret ENDP CheckGraphics ;---------------------------------------------------------------------------- ; CheckMem Performs a manual memory test ;---------------------------------------------------------------------------- ; ; Does a manual memory test by attempting to read and write values at ; various places in memory, determining when they fail. ; ; Entry: AX - Maximum amount of memory installed ; BX - Offset of bank switching routine ; CX - Value in AX to set 256 color mode ; DX - Value in BX to set 256 color mode ; ; Exit: [VideoMem] set to the correct value ; ; Registers: AX,BX,CX,DX ; ;---------------------------------------------------------------------------- PROC CheckMem push si push di push bp push ax push bx push cx push dx ; Find the current video mode so that we can restore it easily mov ah,0Fh ; Get current video mode service int 10h mov [OldBIOSMode],al ; Save old video mode mov [Old50Lines],0 ; Default to non-50 line mode mov ax,1130h ; AH := INT 10h function number ; AL := Get character gen information mov bh,00 ; Get contents of INT 1Fh xor dl,dl ; Clear dl int 10h ; Determine number of lines (in dl) cmp dl,49 ; 50 line mode? jne @@SetMode ; No, must have been 25 lines mov [Old50Lines],1 ; Yes, 50 line mode was on @@SetMode: pop bx ; Pop value for BX pop ax ; Pop value for AX int 10h ; Set the video mode ; Now perform the memory check mov ax,0A000h mov es,ax pop bx pop bp shr bp,6 ; BP := maximum number of 64k banks xor di,di ; ES:DI -> offset in video RAM mov dx,4 ; Start by checking for 256k RAM @@CheckLoop: mov ax,dx dec ax call bx ; Setup to to read/write maxbank-1 mov cx,[es:di] ; Read a value from memory mov si,cx ; Save the old value xor cx,0AAAAh ; Modify the value mov [es:di],cx ; Put the value back again mov cx,[es:di] ; Read the value back again mov [es:di],si ; Put the old value back xor cx,0AAAAh ; Attempt to get old value back cmp cx,si ; Old value the same? jne @@TestFailed ; The test failed, so we ran outa memory! mov ax,dx shr ax,1 dec ax call bx ; Setup for (bank/2) - 1 mov ax,si xor ax,5555h mov [es:di],ax ; Set modified value mov ax,dx dec ax call bx ; Setup for bank-1 mov ax,[es:di] xor ax,5555h cmp ax,si je @@TestFailed cmp dx,bp ; Have we reached maximum amount? je @@FullMemory ; Yes, so we have maximum memory... shl dx,1 ; Keep on trying jmp @@CheckLoop @@FullMemory: shl dx,1 ; Indicate that we would have failed ; on next bank @@TestFailed: shl dx,5 ; DX := amount of video memory mov [VideoMem],dx ; Save the memory value found ; Restore the old video mode before leaving mov ah,0 ; Set video mode service mov al,[OldBIOSMode] ; Get old BIOS mode number int 10h ; Set the video mode cmp [Old50Lines],0 ; Was 50 line mode set? je @@Exit ; No, don't set it up mov ax,1112h ; AH := INT 10h function number ; AL := 8x8 character set load mov bl,0 ; BL := block to load int 10h ; load 8x8 characters into RAM @@Exit: pop bp pop di pop si ret ENDP CheckMem ;---------------------------------------------------------------------------- ; NCRSwitch NCR 77C22E bank switching routine ;---------------------------------------------------------------------------- ; ; Entry: AL - Bank number to switch to ; ;---------------------------------------------------------------------------- PROC NCRSwitch push dx shl al,2 ; Change 64k bank into 16k bank number mov ah,al mov al,18h mov dx,3C4h out dx,ax ; Set write bank number mov al,1Ch out dx,ax ; Set read bank number pop dx ret ENDP NCRSwitch ;---------------------------------------------------------------------------- ; ET3000Switch ET3000 bank switching routine ;---------------------------------------------------------------------------- ; ; Entry: AL - Bank number to switch to ; ;---------------------------------------------------------------------------- PROC ET3000Switch push dx and al,7 ; Mask out bottom 3 bits mov ah,al ; Combine read and write bank values in al shl ah,3 or al,ah or al,40h ; Set bit 6 to select 64k segments mov dx,3CDh ; Point to memory segment register out dx,al ; Set the new bank value pop dx ret ENDP ET3000Switch ;---------------------------------------------------------------------------- ; AHEADASwitch Ahead A bank switching routine ;---------------------------------------------------------------------------- ; ; Entry: AL - Bank number to switch to ; ;---------------------------------------------------------------------------- PROC AHEADASwitch push dx mov ch,al mov dx,03CCh ; bit 0 in bit 5 of Misc Output reg in al,dx ; Read Misc output register mov dl,0C2h and al,11011111b shr ch,1 ; Need to set the bit? jnc @@SkpA ; No, so skip it or al,00100000b @@SkpA: out dx,al ; Set the new value mov dx,3CEh ; bits 3-1 in bits 2-0 of Segment Reg mov al,0Dh ; Index 0Dh for segment reg mov ah,ch ; ch contains top three bits shr 1 out dx,ax ; Set the new value pop dx ret ENDP AHEADASwitch ;---------------------------------------------------------------------------- ; AHEADBSwitch Ahead B bank switching routine ;---------------------------------------------------------------------------- ; ; Entry: AL - Bank number to switch to ; ;---------------------------------------------------------------------------- PROC AHEADBSwitch push dx mov ah,al ; Combine read/write bank numbers shl ah,4 or ah,al mov al,0Dh ; Index of Bank Switch register mov dx,3CEh out dx,ax ; Set the register pop dx ret ENDP AHEADBSwitch ;---------------------------------------------------------------------------- ; P2000Switch Primus P2000 bank switching routine ;---------------------------------------------------------------------------- ; ; Entry: AL - Bank number to switch to ; ;---------------------------------------------------------------------------- PROC P2000Switch push dx mov dx,3D6h out dx,al ; Set read bank inc dx out dx,al ; Set write bank pop dx ret ENDP P2000Switch ;---------------------------------------------------------------------------- ; Find6845 Determine if a 6845 CRTC is at the required port ;---------------------------------------------------------------------------- ; ; Routine detects the presence of the CRTC on an MDA, CGA, or HGC. ; The technique is to write and read register 0Fh of the chip (Cursor ; Location Low). If the same value is read as written, assume the chip ; is present at the specified location. ; ; Entry: DX = port address of 6845 CRTC ; ; Exit: Carry flag is set if 6845 is present ; ; Registers: AX,CX,DX ; ;---------------------------------------------------------------------------- PROC Find6845 near mov al,0Fh out dx,al ; Select 6845 reg 0Fh (Cursor low) inc dx in al,dx ; AL := current Cursor Low value mov ah,al ; Preserve in AH mov al,66h ; AL := arbitrary value out dx,al ; Try to write 6845 mov cx,100h @@Wait: loop @@Wait ; wait for 6845 to respond in al,dx xchg ah,al ; AH := returned value ; AL := original value out dx,al ; Restore original value cmp ah,66h ; test whether 6845 responded jne @@Exit ; Jump if it didn't (cf is reset) stc ; Set carry if 6845 present @@Exit: ret ENDP Find6845 endcodeseg detectgr END ; End of module