                    VGA

     ᬠਢ  ॣ VGA  ᯮ
ணࠬ⠬  אַ ࠢ ஫஬  室
樮 ⥬, ⠪  ᯮ짮 㭪権 DOS
  樨 ।    
ࠧ.  


     : INPUT STATUS REGISTER ONE
     :           3BAh Monochrome Mode Read Only
                           3DAh Color Mode Read Only

Ŀ
             INPUT STATUS REGISTER ONE                     
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
                     Display Enable        
                   Light Pen Strobe      
                 Light Pen Switch      
               Vertical Retrace      
             Diagnostic 1          
           Diagnostic 2          
       Not Used              


    DISPLAY ENABLE:
      D0
      1         뢠  , ᯫ ⪫祭. 
                ந室  ६ ⭮ 室  ப
                 .
                ⥬ ulti Function Video Controller
                 ࡨࠦ /video RAM, ⮬
                 video RAM   ந
                  ६,  뢠  ⮬
                ࠧ襭 ⮡ࠦ ࠧ
                [ࠦ]

    LIGHT PEN STROBE:
      D1
      1         뢠,  ⠭ 奬-饫
                ᢥ⮢ .
      0         뢠,  奬-饫 ᢥ⮢ 
                饭  室 .
    LIGHT PEN SWITCH:
      D2
      1         뢠,  ४⥫ ᢥ⮣ 
                ࠧ.
      0         뢠,  ४⥫ ᢥ⮢ 
                .

    VERTICAL RETRACE:
      D3
      1         뢠  ,  RT 室 
                ஬⪥ ⭮ 室  .
      0         뢠,  CRT 室  ஬⪥
                ᯫ.

    DIAGNOSTIC 1,0:
      D5  D4            color
                output ਡ⭮ ஫.  D5  D4
                ॣ Color Plane Enable ਡ⭮
                ஫ ।,  olor Output
                ᯮ.

    Color Plane   Input Status
    Register      Register One
        D5  D4    D5       D4
        0   0     Red      Blue
        0   1     S.Red    S.Green
        1   0     S.Blue   Green
        1   1     Not Used Not Used
.
    SEQUENCER:

     : EGA SEQUENCER INDEX
     :           3C4h Write Only

Ŀ
             EGA SEQUENCER INDEX                           
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
                 Sequencer Index            
       Not Used                   


    SEQUENCER INDEX:
      D2  D1  D0    㦭 ॣ  3C5h
      0   0   0   00h Reset Register
      0   0   1   01h Clocking Mode Register
      0   1   0   02h Map Mask Register
      0   1   1   03h Character Map Select Register
      1   0   0   04h Memory Mode Register
      1   X   X    㣨 樨  ᯥ稢


    MAP MASK:

Ŀ
             INDEX = 02h MAP MASK                          
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
                     Enable Plane 0             
                   Enable Plane 1             
                 Enable Plane 2             
               Enable Plane 3             
       Not Used                   


    ENABLE PLANE:
      D3,D2,D1,D0   ࠧ蠥   
                  ᮮ⢥  .
                  ६  ந  ⮬
                  砥,    襬 ஢
                  室   (1). 
                  0-1  2-3  ० ODD/EVEN (࠭
                  ॣ஬ Memory Mode D2)  
                      祭 ᪨ .
.
       : CRTC INDEX
       :           3B0h, 3B2h, 3B4h, or 3B6h
                             MONOCHROME MODE Write Only
                             3D0h, 3D2h, 3D4h or 3D6h COLOR
                             MODE Write Only

Ŀ
             CRTC INDEX                                    
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
             CRTC Data Index            
       Special Function           


      CRTC DATA INDEX:
        D4-D0

 D4  D3  D2  D1  D0    HEX  R#  REG.NAME
 0   0   0   0   0     W     00h  R0  Horizontal Total
 0   0   0   0   1     W     01h  R1  Horizontal Display End
 0   0   0   1   0     W     02h  R2  Start Horizont. Blanking
 0   0   0   1   1     W     03h  R3  End Horizontal Blanking
 0   0   1   0   0     W     04h  R4  Start Horizontal Retrace
 0   0   1   0   1     W     05h  R5  End Horizontal Retrace
 0   0   1   1   0     W     06h  R6  Vertical Total
 0   0   1   1   1     W     07h  R7  CRTC Overflow
 0   1   0   0   0     W     08h  R8  Preset Row Scan
 0   1   0   0   1     W     09h  R9  Maximum Scan Line
 0   1   0   1   0     W     0Ah  RA  Cursor Start
 0   1   0   1   1     W     0Bh  RB  Cursor End
 0   1   1   0   0    R/W    0Ch  RC  Start Address High
 0   1   1   0   1    R/W    0Dh  RD  Start Address Low
 0   1   1   1   0    R/W    0Eh  RE  Cursor Location High
 0   1   1   1   1    R/W    0Fh  RF  Cursor Location Low
 1   0   0   0   0     W     10h  R10 Vertical Retrace Start
 1   0   0   0   0     R     10h  R10 Light Pen High
 1   0   0   0   1     W     11h  R11 Vertical Retrace End
 1   0   0   0   1     R     11h  R11 Light Pen Low
 1   0   0   1   0     W     12h  R12 Vertical Display End
 1   0   0   1   1     W     13h  R13 Offset
 1   0   1   0   0     W     14h  R14 Underline Location
 1   0   1   0   1     W     15h  R15 Start Vertical Blanking
 1   0   1   1   0     W     16h  R16 End Vertical Blanking
 1   0   1   1   1     W     17h  R17 Mode Control
 1   1   0   0   0     W     18h  R18 Line Compare

    SPECIAL FUNCTION:
      D7,D6,D5     ᯮ
.

    CURSOR START : 쪮 .

Ŀ
             INDEX = 0Ah CURSOR START                      
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
             ROW Scan Cursor Begins     
       Not Used                   


    ROW SCAN CURSOR BEGINS:
       D4-D0   ,   ப ࠢ
              ᮤন ॣ,  ᯫ 㪠뢠
              ⠪,  ࠢ ᮤন ॣ஢ OEh 
              OFh.

    CURSOR END: 쪮 

Ŀ
             INDEX = 0Bh CURSOR END                         
Ĵ
 BIT  7  6  5  4  3  2  1  0                                
                                                    
             Row Scan Cursor Ends          
         Cursor Skew Control           
       Not Used                      


    ROW SCAN CURSOR ENDS:
       D4-D0   ᫨  ப 㤥 ࠢ  ॢ蠥
               ᮤন ⮣ ॣ ,  ⮡ࠦ
                 ᯫ  㤥 .

    CURSOR SKEW CONTROL:
      D6  D5    祭, ணࠬ஢  ⮬ ॣ
                । ४ , ७ 
                character clocks.
      0    0    প  .
      0    1     ন   character clock.
      1    0     ন   character clocs .
      1    1     ন   character clocs.


    START ADDRESS HIGH: ⥭ / .

Ŀ
             INDEX = 0Ch START ADDRESS HIGH                
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
       High Order Start Address   


      ᥬ ᮪ ⮢ 16- ⮢ ॣ,
 ᯮ  । 砫쭮 
࠭  ᯫ.


    START ADDRESS LOW: ⥭ / 

Ŀ
             INDEX = 0Dh START ADRESS LOW                  
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
       Low Order Start Address    


     ᥬ  ⮢ 16- ⮢ ॣ ,
ᯮ㥬  । 砫쭮  ࠭
 ᯫ .


    CURSOR LOCATION HIGH: ⥭/ .

Ŀ
             INDEX = 0Eh CURSOR LOCATION HIGH              
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
       High Order Cursor Location 


     ᥬ  ⮢ 16-⮢ ᭮ ॣ,
ᯮ㥬  ।    .


    CURSOR LOCATION LOW: ⥭/.

Ŀ
             INDEX = 0Fh CURSOR LOCATION LOW               
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
       Low Order Cursor Location  


     ᥬ  ⮢ 16-⮢ ᭮ ॣ,
ᯮ㥬  ।    .


    OFFSET: 쪮 .

Ŀ
             INDEX = 13h OFFSET                            
Ĵ
 BIT  7  6  5  4  3  2  1  0                               
                                                   
       Logical Line Width         


     ॣ ᮤন 祭 , ᯮ㥬 
ᬥ饭 稪 ᮢ   砫 ᫥饩
⮡ࠦ ⥪⮢ ப.  祭 ।⠢
ᮡ ᫮   ᫮ ,  ᨬ  CRTC
clocking mode,   ⥪⮢ ப.


    LINE COMPARE: 쪮 .

Ŀ
   INDEX = 18h LINE COMPARE                                 
Ĵ
   BIT  7 6 5 4 3 2 1 0                                     
                                                    
           Line Compare Value           


 8  ⮢ 9- ⮢ ॣ Line Compare.
 8 室  ॣ ९ CRTC.  
ᯫ ⠭   0  砫 ᫥ 
ப ᫥ ⮣,  ᫮ ⮡ࠦ  ᯫ ப
⠭ ࠢ ᮤন ⮣ ॣ.

.

     :  GRAPHICS 1 AND 2 ADDRESS
     :            3CEh ⮫쪮 

Ŀ
   GRAPHICS 1 AND 2 ADDRESS                                 
Ĵ
   BIT  7 6 5 4 3 2 1 0                                     
                                                    
               Graphics Address             
           Not Used                     


    GRAPHICS ADDRESS:
     D3  D2  D1  D0    Hex    Register Name
     0   0   0   0     00    Set/Reset
     0   0   0   1     01    Enable Set/Reset
     0   0   1   0     02    Color Compare
     0   0   1   1     03    Data Rotate
     0   1   0   0     04    Read Msp Select
     0   1   0   1     05    Mode
     0   1   1   0     06    Miscellaneous
     0   1   1   1     07    Color Don't Care
     1   0   0   0     08    Bit Mask


     :  GRAPHICS CONTROLLER DATA
     :            3CFh ⮫쪮 

    SET/RESET:

Ŀ
   INDEX = 00h SET/RESET                                    
Ĵ
   BIT  7 6 5 4 3 2 1 0                                     
                                                    
           Refer to Mapping Table       


⨢  ⮢  ⮬ ॣ ਢ  ࠧ
Mapping Table  砫 ⮣ ࠧ.  ॣ ࠧ蠥
  祭    ᪮
ᮮ⢥ ⠬  ⮬ ॣ : 1=Set , 0=Reset
.  ॣ  ⨢,  Graphics
Controller 室   Mode 0,  Enable Set/Reset
⨢.  ॣ 䥪⨢ ⮫쪮   
.
.
    ENABLE SET/RESET:

Ŀ
   INDEX = 01h ENABLE SET/RESET                             
Ĵ
   BIT  7 6 5 4 3 2 1 0                                     
                                                    
           Refer to Mapping Table       


⨢    ⮬ ॣ ਢ  Mapping
Table  砫 ⮣ ࠧ.  ॣ ஫
⨢ Set/Reset ॣ. ணࠬ஢   
logie 1 ࠧ蠥 ᮮ⢥騩   ॣ Set/Reset .
Logie 0 頥 ᮮ⢥騩  Set/Reset, 
    .

    COLOR COMPARE:

Ŀ
   INDEX = 02h COLOR COMPARE                                
Ĵ
   BIT  7 6 5 4 3 2 1 0                                     
                                                    
           Refer to Mapping Table       


⨢    ⮬ ॣ ਢ  Mapping
Table  砫 ⮣ ࠧ.  ॣ ।
⠫ 梥  Read Mode1(. Mode Register).  ⮬
०,   뢠   ᯫ, 
  㤥   1    ,
   4 ᪮  ᮣ  祭 
ॣ Color Compare (. ⠡ ). ஢
 ⮫쪮 ᪮, ࠧ襭 ॣ஬ Color Don't
Care.

                       Color Compare         Ŀ
                         Register     ĴVRAM Plane 0   
                                            1 1 0 1 1 0 1 0
                       Ŀ            
      C.P.U.             Bit        Ŀ
Ŀ             ĴVRAM Plane 1   
                      0 = 1              1 1 0 0 1 1 0 1
0 1 0 0 1 0 0 0Ĵ 1 = 1              
                      2 = 0              Ŀ
       3 = 1 ĴVRAM Plane 2   
                        4 = X              1 0 1 1 0 1 1 0
ࠬ 뢠    5 = X              
ࠢ  GP A = 0,   6 = X              Ŀ
GP B = 1                7 = X ĴVRAM Plane 3   
                        8 = X              1 1 1 1 1 0 1 1
                                    
.
    DATA ROTATE:

Ŀ
   INDEX = 03h DATA ROTATE                                  
Ĵ
   BIT  7 6 5 4 3 2 1 0                                     
                                                    
                Rotate Count                 
              Function Select              
           Not Used                     


    ROTATE COUNT:
     D2-D0    㦥 3 ⮢ 筮 祭
              । ᫮    饭
                   
              㦭 㧨  3   筮 0. 
              㭪  Rotate Logie Right (.
              ⠡ ).

                     ROTATE COUNT
                   7 6 5 4 3 2 1 0
                  Ŀ
                  XXXXX101   Count = 5h
                  

         CPU BUS                            VIDEO MEMORY
     7 6 5 4 3 2 1 0                       7 6 5 4 3 2 1 0
    Ŀ                     Ŀ
Ĵ01001101Ŀ    > 01101010
                       
<

    FUNCTION SELECT:
      D4  D3     ᯮ  롮 ᪨
              㭪権 ,   ।⥫쭮
              ଠ஢  䨪஬   
              묨 묨, ࠭묨 ॣ஬ Write Mode.
      D4  D3
      0   0     .
      0   1   Logical AND c 䨪஢묨 묨
      1   0   Logical OR  䨪஢묨 묨
      1   1   Logical XOR  䨪஢묨 묨.
.
    READ MAP SELECT:

Ŀ
   INDEX = 04h READ MAP SELECT                              
Ĵ
   BIT  7 6 5 4 3 2 1 0                                     
                                                    
                Map Select                   
           Not Used                     


    MAP SELECT:
     D2-D0    ॣ ᯮ  롮 Video Memory
             Plane,  㤥 뢠 ஬.
              ॣ 롨ࠥ ᪮  0  7, 
             ணࠬ஢  筮 ᫥ 
             樨 ⥭. ᪨  ᪮⥩
              ஫ Graphicr Position A u B.
             (GP A, GP B).


    MODE:

Ŀ
   INDEX = 05h MODE                                         
Ĵ
   BIT  7 6 5 4 3 2 1 0                                     
                                                    
                 Write Mode                   
                Not Used                     
               Read Mode                    
              Odd/Even                     
             Shift Register Mode          
           Not Used                     

.
    WRITE MODE:
     D1  D0     롨 ० .  
             業 ० ,  ஫
             室    Video Planer.
     0   0   Write Mode 0: Data Rotate,Logical  Function u
             Set/Reset ࠡ뢠  ⮬ ०.
     0   1   Write Mode 1: ⨢ Video Memory Plane(s)
             뢠  ᮤন 䨪஢  32-
             ⮢ , 䨪 㦠
             ।騬 뢠   .
     1   0   Write Mode 2:   ⮬ ०  ,
             ᮮ⢥饣  Video Plane
             (஫㥬 GPA  GPB), ᯮ 
             祭 8    ⭮,
             ਬ, Write Mode 2;   -
              ``10101100``. ⭮ 3 㤥
             뢠  8 ⠬( )  ⠪ 
             祭,   3  .

     D1    D0
     1     1    筮    ᯮ.  
                 ᠬ,  Write Mode 1.

    READ MODE:
         D3
         0      뢠   ⨢
               Video Memory Plane.

         1    蠥 Color Compare Register (஡
              .  Color Compare).

    ODD/EDEN:
         D4
         0     롮 Read Plane ஫, 
               ᪮  뢠 .

         1     AO   頥  0
              ॣ Read Plane Select (.Read Plane
              Select). ⮬ A 0 ।,  
              ᪮  뢠 ,  ⭮
               ⭮.

    SHIFT REGISTER MODE:
         D5    ॣ ஫,  ࠧ
                Video Memory Planes ᬥ 
              ᥪ  ਡ⭮ ஫ 
              Graphics Mode. ᫥  CRT 뢠 
                   ᬥ饭  16
              . ᫥ ⠡ 뢠 冷
              ᬥ饭  (P1 = Memory Plane 1 
              ..)
.
D5 = 0:

     Ŀ
        P1        P0                  COLOR Palette
     Ĵ
      01234567  01234567 Ŀ      Ŀ
                            
                                                   
                Ŀ                       
                   P1          Ĵ A0         
     Ĵ                        
      00000000  01234567 Ŀ                  
          Ĵ A1         
                                                    
                                                    
     Ŀ     Ĵ A2         
        P3        P2                            
     Ĵ                       
      01234567  01234567                   
          Ĵ A3         
                                                   
                Ŀ                       
                   P3                
     Ĵ     
      00000000  01234567 
     

D5 = 1:

     Ŀ
      P1   P0   P1   P0               COLOR Palette
     Ĵ
     1357 135702460246 Ŀ      Ŀ
                            
                                                   
                Ŀ     Ĵ A0         
                 P1   P0                          
     Ĵ                        
     0000 000013571357 Ĵ A1         
                             
                                                    
     Ŀ                        
      P3   P2   P3   P2       Ĵ A2         
     Ĵ                       
     1357 135702460246                   
                             
                                 Ĵ A3         
                Ŀ                       
                 P3  P2                         
     Ĵ           
     0000 000013571357 
     
.
    COLOR DON`T CARE:

Ŀ
   INDEX = 07h Color Don't Care                         
Ĵ
    BIT 7 6 5 4 3 2 1 0                                 
                      Refer to Mapping Table    
                                                        


⨢  ⮢  ⮬ ॣ ᠭ  Mapping
Table  砫 ⮣ ࠧ.  ॣ 
⮫쪮  Read Mode 1.

쪮    ᮮ⢥ Video Memory
Plane  color compare ( ࠦ  ⠡ GPA  GPB).

    BIT MASK:

Ŀ
   INDEX = 08h Bit Mask                                 
Ĵ
    BIT 7 6 5 4 3 2 1 0                                 
                                                
           Bit Mask                


    BIT MASK:
         0         ᮮ⢥騩  
                 ᪮    묨 
                䨪஢ .  
                㦠 Video memory ⥭ .
         1        ᮮ⢥騩   ᪮
                  ࠭ ० 
                 묨 CPU.
.
    ATTRIBUTES CONTROLLER:

    ATTRIBUTE ADDRESS AND DATA:
 Attribute Address  Data  ॣࠬ
⮫쪮 ,         1 0
(3C0h). ⮡ ᭠砫  ॣ Attribute Address
  뢠   1 0  3BAh  3DAh.
 ਢ  ᭮ ﭨ flip-flop 롮
address/data.    3C0h  㦭 ਡ ᮬ
   ॣ  ᫥饩  
 ४砥 ਣ 롮 /. ⥫쭠
 ४砥  ᮬ  묨  ⮬ 
.

    ATTRIBUTE ADDRESS:
    First Write to 3C0h

Ŀ
   ATTRIBUTE ADDRESS                                  
Ĵ
    BIT 7 6 5 4 3 2 1 0                               
                                              
            Attribute Address         
           Palette Address Source    
         Not Used                  
                                                      


    INDEX:
     D4  D3  D2  D1  D0
     0   X   X   X   X        00h - 0Fh Palette Registers
     1   0   0   0   0        10h Mode Control
     1   0   0   0   1        11h Over-scan Color
     1   0   0   1   0        12h Color Plane Enable
     1   0   0   1   1        13h Horizontal Picture Element
                                                  Panning

    PALETE ADDRESS SOURCE:
      D5
      0      襭 㧪 Palette ॣ஢. 
             D3-D0 ਡ⭮ ॣ ᮢ ਬ
              室 color palette address.

      1       ਬ  室 
              梥⮢.
.
    PALETTE:

Ŀ
   INDEX = 00h-0Fh Palette Registers                  
Ĵ
    BIT 7 6 5 4 3 2 1 0                               
                                              
                Blue                      
               Green                     
              Red                       
             Secondary Blue/Mono Video 
            Secondary Green/Intensity 
           Secondary Red             
         Not Used                  


     ॣ 16 .    ॣ஢
ᮮ⢥   樨  4 室
᪮  ⥬ ਡ⭮ ஫.

    FUNCTION DIAGRAM:

                          Sec.Red              Ŀ
                          Ĵ           
                           Sec.Green           Direct    
                           Ĵ           
                            Sec.Blue          Drive     
                            Ĵ           
                             Red             Video     
                             Ĵ           
                              Green         Out       
                              Ĵ           
                               Blue                  
                               Ĵ           
Ŀ                                            
      Ŀ Ŀ       
Video            00h 100101 
Shift ĿĴ A0         
Regis-ÿĴ A1                
ter   Ĵ A2         
      Ĵ A3     /Fh 011001 
                       
    
             Attributes Controller Palette

     室   㤥 ⠪:

For A3-0 = 00h:ONS.Red            For A3-0 = OFh:OFFS.Red
           OOFS.Green                        ONS.Green
           OFFS.Blue                         ONS.Blue
           ONRed                             OFFRed
           OFFGreen                          OFFGreen
           ONBlue                            ONBlue
.
    COLOR PLANE ENABLE:

Ŀ
   INDEX = 12h Color Plane Enable                     
Ĵ
    BIT 7 6 5 4 3 2 1 0                               
                                              
             Enable Color Plane        
           Video Status MUX          
         Not Used                  
                                                      


    ENABLE COLOR PLANE
    D3 -  D0
    1          ᮮ⢥饩 Video Memory plane
              (plane 3-0) ਬ   梥⮢.
    0         室  梥⮢ ᮥ  logic 0.

    VIDEO STATUS MUX:
      D5  D4      롨 2  6 梥⮢ 室 
                Status Port (.  3BAh, 3DAh  D5 
                D4).
                   Status Port
                       D5               D4
      0   0           Red             Blue
      0   1          S.Red           S.Green
      1   0          S.Blue           Green
      1   1         Not Used         Not Used


    HORIZONTAL PICTURE ELEMENT PANNING:

Ŀ
   INDEX = 13h Horizontal Pel Panning                 
Ĵ
    BIT 7 6 5 4 3 2 1 0                               
                                              
             Horizontal Pel Panning    
         Not Used                  
                                                      


    HORIZONTAL PEL PANNING
      D3 - D0     ॣ ᯮ  ਧ⠫쭮
                 ப⪨.  8 Pels  character modes 
                 ॣ 筮 ணࠬ㥨  祭
                 0. ⮡ࠦ 祭 ᬥ頥 
                 । ᫮ 祪 ,
                 ।塞   ⮣ ॣ.
                 ᨬ쭮 ࠧ蠥 7.  9 窠 
                 character modes  ॣ 筮
                 ணࠬ  祭 8.
                 ணࠬ஢ 祭 0-7 㤥 
                  ᬥ ࠦ .
