qa.hlp (Table of Contents; Topic list)
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Int 10H Function 12H Subfunction 35H
   Summary  Notes  Back
──────────────────────────────────────────────────────────────────────────────
 
  Description:  Switch Active Display      [MCGA] [VGA]
 
  Allows selection of one of two video adapters in the system, when memory
  usage or port addresses conflict between the two adapters.
 
  Input                                     Output
  ══════════════════════════════            ═══════════════════════════════
  AH=12H                                    If function supported
  AL=switching function                     AL=12H
     00H to disable initial                 and, if called with AL=00H
      video adapter                         or 02H
     01H to enable system board             Video adapter state information
      video adapter                         saved in caller's buffer
     02H to disable active                  or, if called with AL =03H
      video adapter                         Video adapter state restored
     03H to enable inactive                 from information in caller's
      video adapter                         buffer.
  BL=35H
  ES:DX=segment:offset of 128-byte buffer
    (if AL =00H, 02H, or 03H)
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