qa.hlp (Table of Contents; Topic list)
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Int 10H Function 1BH
   Summary  Notes  Back
──────────────────────────────────────────────────────────────────────────────
 
    The caller's buffer is filled in with information that depends on the
    current video display mode:
 
    Byte(s)      Contents
    ═══════      ════════════════════════════════════════════════════════════
    00H-03H      pointer to functionality information (see next Note)
    04H          current video mode
    05H-06H      number of character columns
    07H-08H      length of video refresh buffer (bytes)
    09H-0AH      starting address in buffer of upper left corner of display
    0BH-1AH      cursor position for video pages 0-7 as eight 2-byte entries;
                 first byte of each pair is y coordinate, second byte is x
                 coordinate
    1BH          cursor starting line
    1CH          cursor ending line
    1DH          active display page
    1EH-1FH      adapter base port address (3BXH monochrome, 3DXH color)
    20H          current setting of register 3B8H or 3D8H
    21H          current setting of register 3B9H or 3D9H
    22H          number of character rows
    23H-24H      character height in scan lines
    25H          active display code (see Int 10H Function 1AH)
    26H          inactive display code (see Int 10H Function 1AH)
    27H-28H      number of displayable colors (0 for monochrome)
    29H          number of display pages
    2AH          number of scan lines
                 00H=200 scan lines
                 01H=350 scan lines
                 02H=400 scan lines
                 03H=480 scan lines
                 04H-FFH=reserved
    2BH          primary character block
                 (see Int 10H Function 11H Subfunction 03H)
    2CH          secondary character block
    2DH          miscellaneous state information
                 Bit(s)          Significance
                 ══════          ═══════════════════════════════════════════
                 0               =1 if all modes on all displays active
                                  (always 0 on MCGA)
                 1               =1 if gray-scale summing active
                 2               =1 if monochrome display attached
                 3               =1 if mode set default palette
                                  loading disabled
                 4               =1 if cursor emulation active
                                  (always 0 on=MCGA)
                 5               =state of I/B toggle (0=intensity, 1=blink)
                 6-7             =reserved
    2EH-30H      reserved
    31H          video memory available
                 00H=64 KB
                 01H=128 KB
                 02H=192 KB
                 03H=256 KB
    32H          save pointer state information
                 Bit(s)          Significance
                 ══════          ════════════════════════════════════
                 0               =1 if 512-character set active
                 1               =1 if dynamic save area active
                 2               =1 if alpha font override active
                 3               =1 if graphics font override active
                 4               =1 if palette override active
                 5               =1 if display combination code (DCC)
                                    extension active
                 6-7             =reserved
    33H-3FH      reserved
 
    Bytes 0-3 of the caller's buffer contain a DWORD pointer (offset in
    lower word, segment in upper word) to the following information about
    the display adapter and monitor:
 
    Byte(s)      Contents
    ═══════      ════════════════════════════════════════════════════════
    00H          video modes supported
                 Bit(s)          Significance
                 ══════          ════════════════════════
                 0               =1 if mode 00H supported
                 1               =1 if mode 01H supported
                 2               =1 if mode 02H supported
                 3               =1 if mode 03H supported
                 4               =1 if mode 04H supported
                 5               =1 if mode 05H supported
                 6               =1 if mode 06H supported
                 7               =1 if mode 07H supported
    01H          video modes supported
                 Bit(s)          Significance
                 ══════          ════════════════════════
                 0               =1 if mode 08H supported
                 1               =1 if mode 09H supported
                 2               =1 if mode 0AH supported
                 3               =1 if mode 0BH supported
                 4               =1 if mode 0CH supported
                 5               =1 if mode 0DH supported
                 6               =1 if mode 0EH supported
                 7               =1 if mode 0FH supported
    02H          video modes supported
                 Bit(s)          Significance
                 ══════          ════════════════════════
                 0               =1 if mode 10H supported
                 1               =1 if mode 11H supported
                 2               =1 if mode 12H supported
                 3               =1 if mode 13H supported
                 4-7             =reserved
    03H-06H      reserved
    07H          scan lines available in text modes
                 Bit(s)          Significance
                 ══════          ════════════════════
                 0               =1 if 200 scan lines
                 1               =1 if 350 scan lines
                 2               =1 if 400 scan lines
                 3-7             =reserved
    08H          character blocks available in text modes (see Int 10H
                 Function 11H)
    09H          maximum number of active character blocks in text modes
    0AH          miscellaneous BIOS capabilities
                 Bit(s)          Significance
                 ══════          ══════════════════════════════════════
                 0               =1 if all modes active on all displays
                                  (always 0 for MCGA)
                 1               =1 if gray-scale summing available
                 2               =1 if character font loading available
                 3               =1 if mode set default palette
                                  loading available
                 4               =1 if cursor emulation available
                 5               =1 if EGA (64-color) palette available
                 6               =1 if color register loading available
                 7               =1 if color register paging mode
                                  select available
    0BH          miscellaneous BIOS capabilities
                 Bit(s)          Significance
                 ══════          ════════════════════════════════════════
                 0               =1 if light pen available
                 1               =1 if save/restore video state available
                                  (always 0 on MCGA)
                 2               =1 if background intensity/blinking
                                  control available
                 3               =1 if get/set display combination
                                  code available
                 4-7             =reserved
    0CH-0DH      reserved
    0EH          save area capabilities
                 Bit(s)          Significance
                 ══════          ══════════════════════════════════════
                 0               =1 if supports 512-character sets
                 1               =1 if dynamic save area available
                 2               =1 if alpha font override available
                 3               =1 if graphics font override available
                 4               =1 if palette override available
                 5               =1 if display combination code
                                  extension available
                 6-7             =reserved
    0FH          reserved
                                    -♦-