заочникиОС / Лабораторные работы / TASM / EXAMPLES / WHEREIS / BIOSMAC

FILENAME: BIOSMAC.DOC

DESCRIPTION: This file documents the BIOS interface macros implemented in
the files IBIOS.MAC and MBIOS.MAC. Note that the only difference between the
two files is that IBIOS.MAC uses TASM's Ideal mode while MBIOS.MAC uses
TASM's MASM mode.


CallBIOS
--------
Function: Calls the specified BIOS interrupt/service.
Input
    Interrupt - Interrupt number
    Service   - Service number
Output
    none
Registers modified: ah, flags
Syntax: CallBIOS    Interrupt, Service


LoadBH
------
Function: Loads BH with the a value. Presumably the video page. If no value
          is provided BH is initialized to 0.
Input
    Value - value to put in BH
Output
    none
Registers modified: bh
Syntax: LoadBH  Value


SetVideoMode
------------
Function: Sets the current video mode.
BIOS Interrupt: 10h     Service: 00h
Input
    Mode - new video mode as defined below
    ----    ----------------------------------------------------
    0h      40x25 Black and White
    1h      40X25 Color
    2h      80x25 Black and White
    3h      80x25 Color
    4h      320x200 4-Color graphics
    5h      320x200 4-Color graphics(color burst off)
    6h      640x200 2-Color graphics
    7h      Monochrome adapter Text display
    8h      160x200 16-Color graphics(PCjr)
    9h      320x200 16-Color graphics(PCjr)
    0Ah     640x200 4-Color graphics(PCjr)
    0Dh     320x200 16-Color graphics(EGA)
    0Eh     640x200 16-Color graphics(EGA)
    0Fh     640x350 Monochrome graphics(EGA)
    10h     640x350 4-Color or 16-Color graphics(EGA)(depends on
            available RAM)
    11h     640x480 2-Color graphics(VGA)
    12h     640x480 16-Color graphics(VGA)
    13h     320x200 256-Color graphics(VGA)
    ----------------------------------------------------
Output
    none
Registers modified: ah, Flags
Syntax: SetVideoMode  Mode

SetCursorShape
--------------
Function: Sets the cursors shape. The parameters passed to it indicate the
          starting and ending scan lines to use when displaying the cursor.
          On a monochrome system the default setting is lines 6-7. Setting
          the scan lines to 0-7 would result in a block cursor. On a color
          system the default setting is 14-15. Setting the starting scan line
          to 15 and the ending scan line to 0 would result in a cursor with a
          line on the top and bottom.
BIOS Interrupt: 10h     Service: 01h
Input
    Starting - starting scan line
    Ending   - ending scan line
Output
    none
Registers modified: ah, cx, Flags
Syntax: SetCursorShape  Starting, Ending

GotoXY
------
Function: Positions the cursor.The new cursor position is provided in the
          parameters Row and Column. The caller can optionally provide the
          video page to use. If Page isn't defined, page 0 is assumed.
BIOS Interrupt: 10h     Service: 02h
Input
    Row (y coordinate)
    Column (x coordinate)
    Page - Display page to check
Output
    none
Register modified: ax, bh, dx, Flags
Syntax: GotoXY  Row, Column, Page

WhereXY
-------
Function: Determines the current cursor position and the cursor's shape. The
          Page parameter indicates the video page to check and is optional.
          If the Page parameter is not specified, page 0 is assumed.
BIOS Interrupt: 10h     Service: 03h
Input
    Page - Display page to check
Output
    ch - Starting line for cursor
    cl - Ending line for cursor
    dh - row (y coordinate)
    dl - column (x coordinate)
Register modified: ax, cx, dx, Flags
Syntax: WhereXY Page

GetCursorShape
--------------
Function: Returns the shape of the cursor. Note that because the BIOS call to
          get the cursor's position returns this information we simply call
          the WhereXY macro.
BIOS Interrupt: 10h     Service: 03h
Input
    none
Output
    ch - starting scan line of cursor
    cl - ending scan line of cursor
Registers modified: ax, cx, dx, Flags
Syntax: GetCursorShape

GetLightPenPos
--------------
Function: Returns the position of the light pen.
BIOS Interrupt: 10h     Service: 04h
Input
    none
Output
    ah = 0 - light pen not down/not triggered
         1 - light pen down/triggered
    ch - pixel vertical coordinate
    bx - pixel horizontal coordinate
    dh - character vertical coordinate
    dl - character horizontal coordinate
Registers modified: ah, bx, ch, dx, Flags
Syntax: GetLightPenPos

SetDisplayPage
--------------
Function: Sets the current display page. Note that the Page parameter is
          optional. If it is not provided, video page 0 is used.
BIOS Interrupt: 10h     Service: 05h
Input
    Page - Desired display  page as defined below
    PAGE    MODE            HARDWARE
    ----    ----            --------
    0-7     00h and 01h     CGA
    0-3     02h and 03h     CGA
    0-7     02h and 03h     EGA
    0-7     0Dh             EGA
    0-3     0Eh             EGA
    0-1     0Fh             EGA
    0-1     10h             EGA
Output
    none
Registers modified: ah, Flags
Syntax: SetDisplayPage  Page

ScrollUp
--------
Function: Scrolls the indicated part of the screen up LineCount times. Any
          blank lines created are initialized to the color indicated in the
          Attrib parameter. The coordinate parameters are optional. If they
          are not provided, the routine scrolls the entire screen. The routine
          assumes there are 80 columns on the screen. However, it checks how
          many lines are currently available (25/43/50) if the coordinate
          parameters aren't provided.
BIOS Interrupt: 10h     Service: 06h
Input
    LineCount - # of lines to scroll
    Attrib - Attribute to use for new lines
    x1 - Upper left column
    y1 - Upper row
    x2 - Lower right column
    y2 - Bottom row
Output
    none
Registers modified: ax, bh, cx, dx, Flags
Syntax: ScrollUp    LineCount, Attrib, x1, y1, x2, y2


ScrollDown
----------
Function: Scrolls the indicated part of the screen down LineCount times. Any
          blank lines created are initialized to the color indicated in the
          Attrib parameter. The coordinate parameters are optional. If they
          are not provided, the routine scrolls the entire screen. The routine
          assumes there are 80 columns on the screen. However, it checks how
          many lines are currently available(25/43/50) if the coordinate
          parameters aren't provided.
BIOS Interrupt: 10h     Service: 07h
Input
    LineCount - # of lines to scroll
    Attrib - Attribute to use for new lines
    x1 - Upper left column
    y1 - Upper row
    x2 - Lower right column
    y2 - Bottom row
Output
    none
Registers modified: ax, bh, cx, dx, Flags
Syntax: ScrollDown    LineCount, Attrib, x1, y1, x2, y2

GetCharAttr
-----------
Function: Reads the character and attribute at the current cursor position of
          the indicated video page. See SetDisplayPage for a definition of
          the different video pages available. Note that the Page parameter
          is optional. If it is not provided, video page 0 is used.
BIOS Interrupt: 10h     Service: 08h
Input
    Page - the video page to check
Output
    ah - attribute
    al - character
Registers modified: ax
Syntax: GetCharAttr Page

PutCharAttr
-----------
Function: Displays a character and attribute 'Count' times starting at the
          current cursor position of the indicated page. Note that the Page
          parameter is optional. If it is not provided, video page 0 is used.
BIOS Interrupt: 10h     Service: 09h
Input
    Character - character to display
    Attribute - attribute to display the character(s) in
    Count     - number of times to display the character
    Page      - Video page to display the characters on
Output
    none
Registers modified: ax, bx, cx, Flags
Syntax: PutCharAttr Character, Attribute, Count, Page

PutChar
-------
Function: Displays a character Count times beginning at the current cursor
          position on the indicated display page. Note that the Page and
          Color parameters are optional. If you provide the Color parameter,
          you must also provide the Page parameter. If the Page parameter is
          not provided, video page 0 is used. If the Color is not provided,
          the character attribute of the current cursor location of the
          indicate video page is used.
BIOS Interrupt: 10h     Service: 0Ah
Input
    Character - character to display
    Count     - number of times to display the character
    Page      - video page to display character(s) on
Output
    none
Registers modified: ax, bx, cx, Flags
Syntax: PutChar Character, Count, Page, Color

SetColorPalette
---------------
Function: Sets the CGA color palette that is used while displaying graphics
          in 320x200 graphics mode(4 & 5). For more information on video
          modes, see SetVideoMode above.
BIOS Interrupt: 10h     Service: 0Bh
Input
    Entry - Color palette id being set
    Color - New color for palette entry
Output
    none
Registers modified: ah, bx, Flags
Syntax: SetColorPalette Entry, Color

PutPixel
--------
Function: Displays a pixel on the screen. Note that the macro may only be
          called while in graphics mode.
BIOS Interrupt: 10h     Service: 0Ch
Input
    X - horizontal position
    Y - vertical position
    Color - color/display method for pixel
Output
    none
Registers modified: ax, cx, dx, Flags
Syntax: PutPixel    X, Y, Color

GetPixel
--------
Function: Reads information about the indicated pixel.
BIOS Interrupt: 10h     Service: 0Dh
Input
    X - horizontal position
    Y - vertical position
Output
    al - pixel information
Registers modified: ax, cx, dx, Flags
Syntax: GetPixel    X, Y

PutTTY
------
Function: Displays text to the console using teletype mode. Note that the
          Color parameter is optional. If the Color parameter isn't provided,
          the character will be displayed using the attribute of the current
          cursor position.
BIOS Interrupt: 10h     Service: 0Eh
Input
    Character - character to display
    Color     - color to display text in.
    Page      - video page to display character(s) on
Output
    none
Registers modified: ax, bx, Flags
Syntax: PutTTY  Character, Page, Color

GetVideoMode
------------
Function: Determines the current video mode and display page.
BIOS Interrupt: 10h     Service: 0Fh
Input
    None
Output
    ah - Number of columns on screen
    al - display mode as defined below
    ----    ----------------------------------------------------
    0h      40x25 Black and White
    1h      40X25 Color
    2h      80x25 Black and White
    3h      80x25 Color
    4h      320x200 4-Color graphics
    5h      320x200 4-Color graphics(color burst off)
    6h      640x200 2-Color graphics
    7h      Monochrome adapter Text display
    8h      160x200 16-Color graphics(PCjr)
    9h      320x200 16-Color graphics(PCjr)
    0Ah     640x200 4-Color graphics(PCjr)
    0Dh     320x200 16-Color graphics(EGA)
    0Eh     640x200 16-Color graphics(EGA)
    0Fh     640x350 Monochrome graphics(EGA)
    10h     640x350 4-Color or 16-Color graphics(EGA)(depends on
            available RAM)
    11h     640x480 2-Color graphics(VGA)
    12h     640x480 16-Color graphics(VGA)
    13h     320x200 256-Color graphics(VGA)
    ----------------------------------------------------
    bh - Active display page
Register modified: ax, bx, Flags
Syntax: GetVideoMode

SetPaletteRegs
--------------
Function: Sets the EGA palette colors. Note that the macro may only be called
          when running on an EGA.
BIOS Interrupt: 10h     Service: 10h
Input
    SubService - Select service as defined below
    SERVICE     FUNCTION
    -------     -----------------------------------------------------
        0       If setting palette register
        1       If setting border color register
        2       If setting all palette registers and border register
        3       If toggling blink/intensity bit(EGA only)
    -----------------------------------------------------------------
    IndexIntensity - palette register or blink/intensity bit as
                     defined below.
    SERVICE         FUNCTION
    -------         -------------------------------------------------
    SubService = 0  Palette register to set
    SubService = 3  IndexIntensity = 0 - Enable intensity
                    IndexIntensity = 1 - Enable blinking
    -----------------------------------------------------------------
    Color - color to store in register
    ListSeg:ListOfs - address of new palette list
Output
    none
Registers modified: ax, bx, dx, es, Flags
Syntax: SetPaletteRegs    SubService, IndexIntensity, Color, ListSeg, ListOfs

ScreenRows
----------
Function: Returns the number of rows available on the screen.
BIOS Interrupt: 10h     Service: 11h
Input
    none
Output
    dl - # of rows on the screen(25/43/50)
Registers modified: ax, dl, Flags
Syntax: ScreenRows

PutString
---------
Function: Displays a string to the indicated video page at the indicated
          position. Note that the Page and Attribute parameters are optional.
          If Page is not supplied, the macro will use page 0 by default. If
          Mode = 0 or 1, Attribute must be supplied. If Mode = 2 or 3,
          Attribute should not be supplied. Note that if you provide the
          Attribute parameter, you must provide the Page parameter also. This
          macro may only be used on IBM-AT, PS/2 and compatible machines.
BIOS Interrupt: 10h     Service: 13h
Input
    Mode - mode to write string in as defined below
    MODE        FUNCTION
    ----        --------
     0          Attribute in bl, string contains character codes only,
                cursor position isn't updated after write.
     1          Attribute in bl, string contains character codes only,
                cursor position is updated after write.
     2          String contains alternating character codes and
                attribute bytes, cursor position isn't updated after
                write.
     3          String contains alternating character codes and
                attribute bytes, cursor position is updated after write.
    --------------------------------------------------------------------
    X - Vertical position to begin display of the string
    Y - Horizontal position to begin display of the string.
    StringSeg - Segment address of the string
    StringOfs - Offset address of string in StringSeg
    Length - Length of the string to be displayed
    Page - Video page to display string to
    Attribute - Optional parameter that indicates the attribute to
                display the string in. This parameter should only be
                provided if Mode = 0 or 1.
Output
    none
Registers modified: ax, bx, cx, dx, bp, es, Flags
Syntax: PutString   Mode, X, Y, StringSeg, StringOfs, Length, Page, Attribute

GetChar
-------
Function: Returns the next character in the BIOS keyboard buffer.
BIOS Interrupt: 16h     Service: 00h
Input
    none
Output
    ah - keyboard scan code
    al - ASCII character
Registers modified: ax, Flags
Syntax: GetChar

GetKbdStatus
------------
Function: Returns the BIOS keyboard status.
BIOS Interrupt: 16h     Service: 01h
Input
    none
Output
    If key wating to be input:
        Zero flag - clear
        ah - keyboard scan code
        al - ASCII character
    If no key waiting to be input:
        Zero flag - set
Registers modified: ax, Flags
Syntax: GetKbdStatus

GetKbdFlags
-----------
Function: Returns the BIOS keyboard flags.
BIOS Interrupt: 16h     Service: 02h
Input
    none
Output
    al - BIOS keyboard flags byte:
    BIT     FUNCTION
    ---     --------
     7      Insert ON
     6      Caps Lock ON
     5      Num Lock ON
     4      Scroll Lock ON
     3      Alt key DOWN
     2      Ctrl key DOWN
     1      Left-Shift key DOWN
     0      Right-Shift key DOWN
Registers modified: al, Flags
Syntax: GetKbdFlags