intro.txt

比较详尽的VGA端口寄存器的文档

Introduction.

This is intended as a collection of documentation about all the various
display adapters for the IBM PC series (and relatives). This is NOT intended
as an introduction to basic VGA programming or as a ready-to-use library.
There are numerous books available on the subject with much better general
VGA/graphics programming sections. Neither is this intended to cover
benchmarking, highlevel graphics algorithms, graphics file formats or specific
graphics programs.

This compilation (c) Copyright 1991-95 Finn Thoegersen. All Rights Reserved.
See the file README.1ST for contact information and conditions for use and
distribution. This file MUST be included unmodified in all distributions.



Terminology/style:

The BIOS calls are mostly taken directly from Ralf Brown's interrupt list
and tends to follow its style and structure.

The register descriptions are sorted by the register number.

All register addresses, data values et cetera are given in hexadecimal.

3d4h means 3D4h when in color mode and 3B4h when in monochrome mode.

3CEh index 3 means register 3CEh is set to 3 and register 3CFh is the
     data port. See notes on register 3C0h under VGA registers.
     On some cards write operations can be done with a single OUTW
     instruction. This may fail on some cards or machines.
     ATI cards require the index to be updated before each access to
     the dataport.

(R)   means the register is Read Only.
(W)   means the register is Write Only.
(R/W) means the register is both Readable and Writable.

Sometimes the size of the registers is given as:
  W(R/W):   The register is 2 bytes (16 bits) long. If the register is
            indexed, the low byte is in the low index (n) and the high byte is
            in the high index (n+1) unless otherwise indicated.
  3(R/W):   The register is 3 bytes (24 bits) long. The lowest byte is in the
            low index (n), the middle byte is in the middle index (n+1) and
            the upper byte in the high index (n+2).


Examples are in Turbo Pascal for readability (your mileage may vary,
I don't discuss politics, choice of computer, editor, keyboard,
programming language or other religious matters on the net  :-) ).
Seriously while assembler can be more precise and/or efficient for the
low-level register access, the complexity and volume of assembler can make
even simple examples totally incomprehensible to all but experts.
Also when I started this my "C" was not up to the task, so ...


A short translation of terms:

Pascal:         C:                  Assembler:         Description:

x:byte;         unsigned char x;    x  DB ?            8 bit unsigned byte

y:word;         unsigned int y;     y  DW ?            16 bit unsigned word.

z:integer;      int z;              z  DW ?            16 bit signed word.

w:longint;      long w;             w  DD ?            32 bit signed Dword

s:string[20];   char s[21];         x DB 20 dup(?)     a 20 character string

$ABCD           0xABCD              0ABCDh             The value 43981
                                                          (ABCD hex)

x:=port[$3CC]   x=inp(0x3CC)        MOV DX,03CCh       Read an 8bit value from
                                    IN AL,DX           I/O port $3CC.

y:=portw[$3CE]  y=inpw(0x3CE)       MOV DX,03CEh       Read a 16bit value from
                                    IN AX,DX           I/O ports $3CE and $3CF

port[$3C2]:=x   outp(0x3C2,x)       MOV DX,03C2h       Write an 8bit value to
                                    OUT DX,AL          I/O port $3C2.

portw[$3CE]:=y  outpw(0x3CE,y)      MOV DX,03CEh       Write a 16bit value to
                                    OUT DX,AX          I/O ports $3CE and $3CF

a shr 3         a>>3                SHR AX,3           Shifts a 3 bits rights
                                                       (Divides by 8).

a shl 3         a<<3                SHL AX,3           Shifts a 3 bits left

inc(a)          a++                 INC [a]            Increments a by 1

dec(a)          a--                 DEC [a]            Decrements a by 1

{Comment}       /* comment */       ;comment           Comments.
'string'        "string"            DB "string"        Text string

procedure x;    void x(void)        x PROC             A procedure/function
var x:integer;    {                  ;Alloc x on stack with no parameters
begin               int x;           _code_            a local variable
  _code_            _code_           ;reset stack      and main body.
end;              }                  RET

function y:     int y(void)        Well you            A function returning
  integer;        {                figure it out!      an integer.
begin
  y:=123;           return(123)
end;              }



The examples use a number of simple rutines:

procedure vio(ax:word);    {Calls interrupt 10h with register AX=parameter ax
                          other registers can be set in the rp structure.
                          rp.ax is set to the return value in the AX register}

function inp(reg:word):byte;   {returns a byte from I/O port REG.}

procedure outp(reg,val:word);  {writes the byte VAL to I/O port REG}

function rdinx(pt,inx:word):word;   {read register PT index INX}

procedure wrinx(pt,inx,val:word);   {write VAL to register PT index INX}

procedure modinx(pt,inx,mask,nwv:word);
                                {In register PT index INX change the bits
                                 indicated by MASK to the ones in NWV
                                 keeping the other bits unchanged).

function tstrg(pt,msk:word):boolean;   {Returns true if the bits specified in
                                        MSK are read/writable in register PT}

function testinx(pt,rg:word):boolean;  {Returns true if all 8 bits of register
                                        PT index RG are read/writable}

function testinx2(pt,rg,msk:word):boolean;
                                   {Returns true if the bits specified in MSK
                                    are read/writable in register PT index RG}

procedure dac2pel;                 {Forces the DAC back to PEL (normal) mode}

procedure dac2comm;                {Enter command mode of HiColor DACs}




References:

Richard F. Ferraro's Programmer's guide to the EGA and VGA cards 2nd ed.
Addison-Wesley 1990. ISBN 0-201-57025-4.

Richard F. Ferraro's Programmer's guide to the EGA, VGA  and Super VGA cards:
 including XGA cards, 3rd ed. Addison-Wesley 1994. ISBN 0-201-62490-7.

George Sutty and Steve Blair's Advanced Programmers Guide to Super VGAs.
Brady Books 1990. ISBN 0-13-010455-8.

John Mueller and Wallace Wang's The Ultimate DOS Programmer's Manual.
Windcrest/McGraw-Hill 1990. ISBN 0-8306-3434-3.

Jake Richter's Power Programming the IBM XGA.
MIS Press 1992. ISBN 1-55828-127-4 (1-55828-124-9 with disc).

Ralf Brown's interrupt list version 47.
    (Simtel: info/inter47a.zip - info/inter47f.zip)
  This is based on contributions from many people, including:
    Dennis Grinberg    [e-mail]         MCGA/VGA
    Michael A. Moran   [e-mail]     VGA INT 10h
    Gary E. Miller     [e-mail]         Paradise, WD90c & Diamond
                                                  Stealth 24X VGA
    Michael Shiels     [e-mail]       ATI VIP INT 10h
    Robert Seals       [e-mail]      ATI VGA Wonder modes
    Peter Sawatzki     [e-mail]      Video7 extended INT 10
    Ben Myers          [e-mail]     Everex Viewpoint VGA, NCR
                                                  77c22 modes
    Mark Livingstone   [e-mail]        TVGA video modes
    Patrick Ibbetson   [e-mail]     NEL Electronics BIOS, Cirrus
                                                  chipsets
    A. Peter Blicher   Oakland, CA                Genoa Super EGA
    Tim Farley         [e-mail]    XGA
    Bent Lynggaard     [e-mail]         misc video
    Frank Klemm        [e-mail]         Diamond Speedstar 24X
    Mikael Rydberg     Sweden                     Cirrus/UM587/etc video modes
    Jens Vollmar       Erlangen, Germany          Trident/C&T video
    Aki Korhonen       [e-mail]            Cirrus Logic BIOS
    Alexi Lookin       [e-mail]     Realtek RTVGA, Avance Logic,
                                                  C&T video
    Win Osterholt      2:512/56.198               Cirrus Logic BIOS 3.02
  And many, many others...


John Bridge's VGAKIT52.
    (Simtel: vga/vgakit52.zip)

Fractint v18.1 source (primarily video.asm).
    (Simtel: graphics/frasr181.zip)

Configuration files and drivers from amongst others:
  CSHOW:        (Simtel:  graphics/cshw860a.zip)
  VPIC:         (Simtel:  gif/vpic60.zip)
  VUIMAGE:      (Simtel:  gif/vuimg340.zip)
  SVGA:         (Simtel:  gif/svga112.zip)

XFree86 3.1.2 - X11 Unix SVGA driver. Available from:
   ftp.x.org:             /contrib/XFree86
   ftp.physics.su.oz.au:  /XFree86
   ftp.win.tue.nl:        /pub/XFree86
   ftp.prz.tu-berlin.de:  /pub/pc/src/XFree86
The XFree86 team includes:
   Robert Baron       [e-mail]
   David Dawes        [e-mail]
   Dirk Hohndel       [e-mail]
   Glenn Lai          [e-mail]
   Rich Murphey       [e-mail]
   Jon Tombs          [e-mail]
   David Wexelblat    [e-mail], [e-mail]
   Thomas Wolfram     [e-mail]
   Orest Zborowski    [e-mail]
E-mail regarding XFree86 should be sent to [e-mail]

PCVISION plus Frame Grabber User's Manual.

Enhanced Graphics Adapter Reference Manual from HP.

Commodore Advanced Graphics Adapter (AGA) manual.

Data sheet for the Analog Devices ADV7160,ADV7162

Data sheets for the Chips and Technologies Inc
   82c455A, 82c456, 82c457, 82c480, 65520/530, 82c425, 82c426, 82c9001A.

Technical Reference Manual for the Cirrus Logic CL-GD542x True Color VGA
 Family, January 1994

Data sheet for the IC Designs ICD2061A

Data sheets for the MUSIC MU9c1880 and MU9c9750

Data sheets for the NCR 77c22E+ and 77c32BLT

Data sheets for the S3 86c911, 86c801/5, 86c928 and 86c964

Data sheet for the Tseng ET3000 and ET4000/W32

Data sheets for the Western Digital PVGA1A and WD90c24A

Data sheet for the Yamaha 6388 VPDC.

Programmer's Guide to the Mach32 Registers (ATI P/N: REG688000-15)
VGA Wonder Programmer's Reference Manual (ATI P/N: PRG2888000-13)
ATI Mouse Driver Programmer's Reference Manual (ATI P/N: PRG188200-12)
Mach64 BIOS Kit (P/N: BIO-C012XX1-04), VGA Register Guide (P/N:
 VGA-C012XX1-04), Register Reference Guide (P/N: RRG-C012XX1-04) and
 Programmer's Guide (P/N: PRG-C012XX1-04)

Truevision Targa+ Hardware Technical Reference Manual.

Device Drivers Kit (DDK)'s for Microsoft Windows 3.1, Windows for Workgroups
 3.11, Windows NT 3.51 and Windows 95 (pre-release).


The following have donated reference material:
H.R.R van Roosmalen and E. Zoer,
   Delft University of Technology,
   The Netherlands    [e-mail]  (no longer valid)
Kendall Bennett       [e-mail]
Joel Finch            [e-mail]
Wieland Weiss         [e-mail]

The following have contributed information:
Darren Senn           [e-mail]
Tomi H Engdahl        [e-mail]
Jori Hamalainen       [e-mail]
Eric ??               [e-mail]
Frank Klemm           [e-mail]
Michael Schindler     [e-mail]
Kendall Bennett       [e-mail]
Danny Halamish        [e-mail]
Daniel Sill           [e-mail]
GARY                  [e-mail]
Paolo Severini        [e-mail]
Royce Shih Wea Liao   [e-mail]

Testers:
Ross Ackland          [e-mail]
Chris Bailey          [e-mail]
Ross Becker           [e-mail]
Darren Brown          [e-mail]
Carlos Henrique Cantu [e-mail]
Murray Chapman        [e-mail]
Frank Dikker          [e-mail]
Michael Eichow        [e-mail]
Torben H. Hansen      100024,[e-mail]
Heikki Julkunen       [e-mail]
Nanda G. Kutty        [e-mail]
Leonardo Loureiro     [e-mail]
Steven Martin         [e-mail]
Jouni Miettunen       [e-mail]
Jack Nomssi           [e-mail]
Juho-Pekka Rosti      [e-mail]
Lode Vande Sande      [e-mail]
Joel Finch            [e-mail]



Disclaimer:

All information herein is presented as is and without warranty.
Use at your own risk.




IBM PC, PC/XT, PC/AT, PCjr, PS/2, Micro Channel, Personal System/2,Enhanced
Graphics Adapter, Color Graphics Adapter, Video Graphics Adapter, IBM Color
Display, IBM Monochrome Display, 8514/A and XGA are trademarks of
International Business Machines Corporation.
MS-DOS, Microsoft and Windows are trademarks of Microsoft, Incorporated.
Hercules is a trademark of Hercules Computer Technology, Inc.
Multisync is a trademark of Nippon Electric Company (NEC).
ATI, VGAWonder, Mach8, Mach32, 8514 ULTRA, GRAPHICS ULTRA, GRAPHICS VANTAGE,
GRAPHICS ULTRA+ and GRAPHICS ULTRA PRO are trademarks of ATI Technologies Inc.
Brooktree and RAMDAC are trademarks of Brooktree Corporation.
SMARTMAP is a trademark of Chips and Technologies, Incorporated.
TARGA is a registered trademark of Truevision, Inc.
Cirrus Logic and SimulSCAN are trademarks of Cirrus Logic, Inc.
HiColor is a trademark of Sierra Semiconducter, Inc.
i386, i486 and Intel are trademarks of Intel Corp.
Inmos and SGS-Thompson are trademarks of SGS-Thompson, Ltd.
IIT is a trademark of Integrated Information Technology, Inc.
Motorola is a trademark of Motorola Corp.
TIGA is a trademark of Texas Instruments.
VBE, VESA and VSE are trademarks of the Video Electronics Standards
Association.
Western Digital, AutoSwitch and TrueShade are trademarks of Western Digital
Corporation.
WEITEK and WEITEK Power are trademarks of WEITEK Corporation
All other product names are copyright and registered trademarks/tradenames of
their respective owners.