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                                   HISTORY                                    

     The Lotus/Intel/Microsoft Expanded Memory Manager  was originally
     a Lotus and Intel project and was announced as version 3.0 in the
     second quarter of 1985  primarily  as  a  means of running larger
     Lotus worksheets  by  transparently  paging  unused  sections  to
     bank-switched  memory.  Shortly  afterward  Microsoft   announced
     support of the standard and version 3.2 was subsequently released
     with support for Microsoft  Windows.  LIM  3.2  supported up to 8
     megabytes  of  paged  memory.  The  LIM  4.0  supports up  to  32
     megabytes of paged memory.

        AST/QUADRAM/ASHTON-TATE ENHANCED EXPANDED MEMORY SPECIFICATION        

     The AQA EEMS maintains upward  compatibility with the LIM, but is
     a superset of functions.

     The AQA EEMS permits  its  pages  to  be scattered throughout the
     unused portion of the machine's address space.

     On August 19,  1987,  the  new  version  of  the  Expanded Memory
     Specification (EMS) was announced by Lotus, Intel  and Microsoft.
     This new version  of  the specification includes many features of
     the  Enhanced Expanded  Memory  Specification  (EEMS)  originally
     developed by AST Reserach, Quadram and Ashton-Tate,  although the
     three original sponsoring  companies  elected not to make the new
     specification upward compatible with EEMS. AST Research says that
     they will endorse EMS 4.0 without reservation.

     The  definitive document for the LIM-EMS  is  Intel  part  number
     300275-004, August, 1987.

     The  page  frame  is located above  the  640k  system  RAM  area,
     anywhere from 0A000h to 0FFFFh. This area is used  by  the  video
     adapters,  network  cards,  and  add-on  ROMs  (as  in hard  disk
     controllers). The page frames are mapped around areas that are in
     use.
 
See Also Programming Specifications Locating Func/40h Func/4Eh/00h Errors


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