HPAVC/HPAVC CD-ROM.iso/pc/BIRTHSRC.ZIP/MODEX.INC

Text File | 1993-11-23 | 12.0 KB | 620 lines

;╔════════════════════════════════════════════════╗
;║  Name:Mode_X_(320x240)_Routines_______  V01.00 ║
;║                                                ║
;║  Modified:22-Nov-93                   FB ║
;╚════════════════════════════════════════════════╝
;
;  All code assumes that ES points to video segment!
;
;**************************************************
; Vars NOT defined in this INC file
;    WriteOffset:word
;    ClipMinX:word
;    ClipMinY:word
;    ClipMaxX:word
;    ClipMaxY:word
;    ClearColor:byte

;General Regs
MISC_OUTPUT        equ   03c2h
MISC_OUTPUT_READ    equ   03cch
FCW            equ   03dah
FCR            equ   03cah
INPUT_STATUS_0        equ   03c2h
INPUT_STATUS_1        equ   03dah

;Sequencer Regs
SC_INDEX        equ   03c4h
SC_DATA         equ   03c5h
MAP_MASK        equ     02h

;CRTC Regs
CRTC_INDEX        equ   03d4h
CRTC_DATA        equ   03d5h

;Graphics Regs
GC_INDEX        equ   03ceh
GC_DATA         equ   03cfh
READ_MAP        equ     04h

;Attribute Regs
ACW_FF            equ   03c0h
ACR_FF            equ   03c1h

;Color Regs
PEL_GET         equ   03c7h
PEL_SET         equ   03c8h
PEL_DATA        equ   03c9h

START_ADDRESS_HIGH  equ     0ch   ;bitmap start address high byte
START_ADDRESS_LOW   equ     0dh   ;bitmap start address low byte

tmppal    db 768 DUP (0)         ;temp palette
DONE    dw 0             ;temp word

; Sequencer Regs
Sequencer   db 003h,021h,00fh,000h
SeqEnd        db 006h

; CRTC Regs
CRTC        db    05fh,04fh,050h,082h,054h,080h,00dh,03eh
        db    000h,041h,000h,000h,000h,000h,003h,0c0h
        db    0eah,02ch,0dfh,028h,000h,0e7h,006h,0e3h
CRTCEnd     db    0ffh

; Graphics Regs
Graphics    db    000h,000h,000h,000h,000h,040h,005h,00fh
GraphicsEnd db    0ffh

;Attribute Regs
Attrib        db    041h,000h,00fh,000h
AttribEnd   db    000h

;--------------------------------------------------------
;
; Scron - Sets ModeX 320x240x256
;    IN     : -
;   OUT     : -
;  Modified : ax,cx,dx,si,di
;  Vars Used: ClearColor
;
Scron        PROC

    mov    dx,INPUT_STATUS_1
Scron1:
    in    al,dx
    test    al,08h
    jz    Scron1    ;vertical sync is active high (1 = active)

    ;turn screen off
    mov    dx,SC_INDEX
    mov    al,1
    out    dx,al
    inc    dx
    in    al,dx
    or    al,00100000b
    out    dx,al

    mov    cx,5
    mov    dx,ACW_FF
    mov    si,offset AttribEnd
Scron6:
    mov    al,cl
    add    al,2fh
    out    dx,al
    mov    al,cs:[si]
    out    dx,al
    dec    si
    loop    Scron6

    mov    cx,10h        ;Bit 5 not set-> allow host access to pal
Scron5:
    mov    al,cl
    dec    al
    out    dx,al
    out    dx,al
    loop    Scron5

    mov    al,30h
    out    dx,al

    mov    dx,SC_INDEX
    mov     ax,0604h
    out    dx,ax        ;disable chain4 mode
    mov    ax,0100h
    out    dx,ax        ;synchronous reset while setting Misc Output
                ; for safety, even though clock unchanged
    ;General Regs
    mov    dx,MISC_OUTPUT
    mov    al,0e3h
    out    dx,al

    mov    si,offset SeqEnd
    mov    dx,SC_INDEX
    mov    cx,5
Scron2:
    mov    al,cl
    dec    al
    mov    ah,cs:[si]
    dec    si
    out    dx,ax
    loop    Scron2

    mov    si,offset CRTCEnd
    mov    dx,CRTC_INDEX
    mov    cx,19h
Scron3:
    mov    al,cl
    dec    al
    mov    ah,cs:[si]
    dec    si
    out    dx,ax
    loop    Scron3

    mov    si,offset GraphicsEnd
    mov    dx,GC_INDEX
    mov    cx,9
Scron4:
    mov    al,cl
    dec    al
    mov    ah,cs:[si]
    dec    si
    out    dx,ax
    loop    Scron4

    mov    dx,SC_INDEX
    mov     ax,0f02h
    out    dx,ax            ;enable writes to all four planes

    sub    di,di            ;point ES:DI to display memory
    mov    al,[ClearColor]
    mov    ah,al
    mov    cx,8000h        ;# of words in display memory
    rep    stosw            ;clear all of display memory

    mov    dx,03c4h        ;turn screen on again
    mov    ax,0101h
    out    dx,ax

    ret

Scron           ENDP

;--------------------------------------------------------
;
; Scroff  - Leaves ModeX
;    IN     : -
;   OUT     : -
;  Modified : ax,dx
;  Vars Used: -
;

Scroff        PROC

    mov    dx,03c4h
    mov    al,1
    out    dx,al
    inc    dx
    in    al,dx
    or    al,00100000b
    out    dx,al
    mov    dx,INPUT_STATUS_1
WaitVS:
    in    al,dx
    test    al,08h
    jz    WaitVS    ;vertical sync is active high (1 = active)

    push    ds
    push    0000
    pop    ds
    ;we didn't use int10h to set video mode
    ;so we the old mode # is still set in
    ;BIOS data area.
    mov    al,ds:[0449h]        ;get previous mode
    mov    ah,00h
    int    10h
    pop    ds
    ret

Scroff          ENDP

;--------------------------------------------------
;
; ScrClear  - Clears 320x240 Window
;    IN     : -
;   OUT     : -
;  Modified : ax,cx,dx,di
;  Vars Used: WriteOffset,ClearColor
;

ScrClear    PROC

    mov     dx,SC_INDEX
    mov     ax,0f02h
    out    dx,ax            ;enable writes to all four planes
    mov    di,[WriteOffset]    ;point ES:DI to display memory
    mov    al,[ClearColor]
    mov    ah,al
    mov    cx,2580h        ;# of words
    cld
    rep     stosw    ;clear all of page

    ret

ScrClear        ENDP

;--------------------------------------------------
; BoxClear  - Clears Window on 4-pixel boundary
;    IN     : cx   (XPos div 4)
;          dx   (YPos)
;          ax   (XLen div 4)
;          bx   (YLen)
;   OUT     : -
;  Modified : ax,bx,cx,dx,di,es
;  Vars Used: WriteOffset,ClearColor
;
;Note: This only clears on 4-pixel boundaries! - but FAST!

BoxClear    PROC


    xor    edi,edi
    mov    di,dx
    shl    di,4                ;multiply by 16
    lea    edi,[edi+4*edi]         ;multiply by 5
    add    di,cx
    add    di,[WriteOffset]        ;point ES:DI to display memory
    mov    dx,80
    sub    dx,ax
    mov    cx,ax
    cld
    mov    dx,SC_INDEX
    mov     ax,0f02h
    out    dx,ax                ;enable writes to all four planes

    mov    al,[ClearColor]

boxclear1:
    push    cx
    rep    stosb                ;clears horizontal line
    pop    cx
    add    di,dx
    dec    bx
    jnz    boxclear1

    ret

BoxClear    ENDP

;--------------------------------------------------
; ClearVGAMem  - Clears VGA Video Memory
;    IN     : -
;   OUT     : -
;  Modified : ax,cx,dx,di,es
;  Vars Used: ClearColor

ClearVGAMem    PROC

    mov     dx,SC_INDEX
    mov     ax,0f02h
    out    dx,ax            ;enable writes to all four planes
    sub    di,di            ;point ES:DI to display memory
    mov    al,[ClearColor]
    mov    ah,al
    mov    cx,8000h        ;# of words in display memory
    cld
    rep    stosw            ;clear all of display memory

    ret

ClearVGAMem     ENDP

;--------------------------------------------------
; SetDot - Sets Dot/Pixel - with clipping
;    IN     : cx   (XPos)
;          dx   (YPos)
;          al   (Color)
;   OUT     : -
;  Modified : bx,cx,dx,es
;  Vars Used: WriteOffset
;

SetDot        PROC

    cmp    dx,[ClipMaxY]
    jae    NoDot
    cmp    dx,[ClipMinY]
    jb    NoDot

    cmp    cx,[ClipMaxX]
    jae    NoDot
    cmp    cx,[ClipMinX]
    jb    NoDot

    push    ax
    xor    eax,eax
    mov    ax,dx
    ;multyply by 80
    shl    ax,4        ;multiply by 16
    lea    eax,[eax+4*eax] ;multiply by 5

    mov    bx,cx
    shr     bx,2
    add    bx,ax            ;offset of pixel in page
    add    bx,[WriteOffset]    ;offset of pixel in display memory

    and    cl,011b         ;pixel's plane
    mov    ax,0100h + MAP_MASK    ;AL = index in SC of Map Mask reg
    shl    ah,cl        ;set only the bit for the pixel's plane to 1
    mov     dx,SC_INDEX ;set the Map Mask to enable only the
    out    dx,ax        ; pixel's plane

    pop    ax
    mov    es:[bx],al  ;draw the pixel in the desired color
NoDot:
    ret
SetDot        ENDP

;--------------------------------------------------
; GetDot - Gets Dot/Pixel
;    IN     : cx   (XPos)
;          dx   (YPos)
;   OUT     : ax   (Color)
;  Modified : bx,cx,dx,es
;  Vars Used: WriteOffset
;

GetDot           PROC

    xor    eax,eax
    mov    ax,dx
    shl    ax,4        ;multiply by 16
    lea    eax,[eax+4*eax] ;multiply by 5
    mov    bx,cx
    shr    bx,2
    add    bx,ax             ;offset of pixel in page
    add    bx,[WriteOffset]     ;offset of pixel in display memory

    mov    ah,cl
    and    ah,011b          ;AH = pixel's plane
    mov    al,READ_MAP         ;AL = index in GC of the Read Map reg
    mov    dx,GC_INDEX         ;set the Read Map to read the pixel's
    out    dx,ax             ; plane

    mov    al,es:[bx]         ;read the pixel's color
    sub    ah,ah             ;convert it to an unsigned int

    ret

GetDot           ENDP

;--------------------------------------------------
; SetCol - Sets Color Register
;    IN     : al   (ColReg)
;          ah   (Red)
;          bl   (Green)
;          bh   (Blue)
;   OUT     : -
;  Modified : ax,bx,dx
;  Vars Used: -

SetCol      PROC

      mov    dx,PEL_SET
      out   dx,al

      inc   dx

      mov    al,ah
      out   dx,al
      mov    al,bl
      out   dx,al
      mov    al,bh
      out   dx,al

      ret

SetCol    ENDP

;--------------------------------------------------
; SetPal - Sets Color Palette
;    IN     : ds:si   (Ptr to Palette)
;          al   (ColReg - Start)
;          cx   (Range)
;   OUT     : -
;  Modified : ax,cx,dx,si
;  Vars Used: -
SetPal        PROC

    mov    dx,PEL_SET
    out    dx,al

    cld
    mov    dx,cx
    shl    cx,1
    add    cx,dx            ;cx=cx*3

    mov    dx,INPUT_STATUS_1
WaitVS1:
    in    al,dx
    test    al,08h
    jz    WaitVS1         ;vertical sync is active high (1 = active)
    mov    dx,PEL_SET+1

palwrite:
    outsb                ;very fast V-cards don't like rep outsb
    loop palwrite

    ret

SetPal        ENDP
;--------------------------------------------------
; FadeIn - Fades Current Palette into New Palette
;    IN     : ds:si   (Ptr to (should-be) Palette)
;          al   (From ColReg)
;          ah   (Stepsize)
;          cx   (Range)
;   OUT     : -
;  Modified : ax,bx,cx,dx,si,di,bp
;  Vars Used: tmppal (local cs)
FadeIn        PROC

    mov    dx,PEL_SET-1    ;PEL Read Mode Reg
    out    dx,al        ;start reading PEL data from color entry FR_COL

    mov    dx,cx
    shl    cx,1
    add    cx,dx        ;cx=cx*3
    mov    dx,PEL_SET+1    ;PEL Data Reg

    mov    bp,cx
    mov    di,offset tmppal
    cld

    push    es
    push    cs
    pop    es
fadein5:
    insb              ;read PEL data
    loop    fadein5
    pop    es

    xor    ecx,ecx
    mov    cl,al
    lea    ecx,[ecx+2*ecx]

    mov    di,offset tmppal
    add    si,cx
    add    di,cx
    xchg    di,si
    mov    cx,bp

fadeagain:
       ;mov    dx,PEL_SET    ;PEL Read Mode Reg
       ;out    dx,al        ;start reading PEL data from color entry FR_COL

    xor    bp,bp        ;number of colregs that actually changed

    push    si
    push    di
    push    cx
fadein1:
    mov    al,byte ptr [di]      ;should-be-value
    mov    bl,byte ptr cs:[si]
    sub    bl,al            ;compare with is-value
    je    fadein2         ;reached destination value?
    jb    fadein3

    cmp    bl,ah
    jge    fadein7
    mov    byte ptr cs:[si],al
    jmp    short fadein4
fadein7:
    sub    byte ptr cs:[si],ah    ;should-be-value < is-value
    jmp    short fadein4
fadein3:
    neg    bl
    cmp    bl,ah
    jge    fadein8
    mov    byte ptr cs:[si],al
    jmp    short fadein4
fadein8:
    add    byte ptr cs:[si],ah
fadein4:

    inc    bp
fadein2:
    inc    di
    inc    si
    loop    fadein1
    pop    cx
    pop    di
    pop    si
    or    bp,bp            ;have any colregs changed?
    je    fadedone

    push    cx
    push    si
    mov    dx,INPUT_STATUS_1
WaitVS2:
    in    al,dx
    test    al,08h
    jz    WaitVS2         ;vertical sync is active high (1 = active)

    mov    dx,PEL_SET        ;PEL Read Mode Reg
    mov    al,0
    out    dx,al            ;start reading PEL data from color entry FR_COL

    mov    dx,PEL_SET+1        ;PEL Data Reg
fadein6:
    outs    dx,byte ptr cs:[si] ;do the deed
    loop    fadein6

    pop    si
    pop    cx
    jmp    short fadeagain
fadedone:
    ret

FadeIn        ENDP
;--------------------------------------------------
; SetPage - Sets page to write to
;    IN     : ax   (WriteOffset)
;   OUT     : -
;  Modified : -
;  Vars Used: -

SetPage     PROC

    mov    [WriteOffset],ax
    ret

SetPage         ENDP

;--------------------------------------------------
; ShowPage - Sets page to show
;    IN     : ax   (DisplayStart)
;   OUT     : -
;  Modified : ax,bx,cx,dx
;  Vars Used: -

;code originally from PC-Mag (?)

ShowPage    PROC

; Wait for display enable to be active (status is active low), to be
; sure both halves of the start address will take in the same frame.
    mov    cx,ax
    mov     bh,cl
    mov     bl,START_ADDRESS_LOW
    mov     cl,START_ADDRESS_HIGH
    mov     dx,INPUT_STATUS_1
WaitDE:
    in    al,dx
    test    al,01h
    jnz    WaitDE    ;display enable is active low (0 = active)

; Set the start offset in display memory of the page to display.
    mov     dx,CRTC_INDEX
    mov     ax,bx
    out     dx,ax   ;start address low
    mov     ax,cx
    out     dx,ax   ;start address high

; Now wait for vertical sync, so the other page will be invisible when
; we start drawing to it.

       ;we are synchronized with VR, so we don't need this...

       ;mov    dx,INPUT_STATUS_1
;WaitVS3:
       ;in    al,dx
       ;test    al,08h
       ;jz    WaitVS3 ;vertical sync is active high (1 = active)

       ret
ShowPage       ENDP

;--------------------------------------------------
;**************************************************