Expanded Memory Specification
SYSTEM OF BANK SWITCHING IN DOS MEMORY MANAGEMENT
Expanded Memory Specification; Expanded Memory System; Expanded Memory; LIM EMS; EMS memory manager; EMS emulator; EEMS; Expanded storage; Expanded memory manager; Expanded Memory Manager; Lotus-Intel-Microsoft; EMMXXXX0; Enhanced Expanded Memory Specification; Enhanced EMS; EMS (memory management); EMS 3.0; EMS 3.2; EMS 4.0; Expanded Memory Specification 3.0; Expanded Memory Specification 3.2; Expanded Memory Specification 4.0; EEMS 3.2; EEMS 3.1; Enhanced Expanded Memory Specification 3.1; Enhanced Expanded Memory Specification 3.2; AQA 3.1; AST Quadram Ashton-Tate; AST/Quadram/Ashton-Tate; AST-Quadram-Ashton-Tate; LIM 3.0; LIM 3.2; LIM 4.0; LIM Expanded Memory Specification; AQA Enhanced Expanded Memory Specification; AQA Enhanced EMS; LIM EMS 3.0; LIM EMS 3.2; LIM EMS 4.0; LIMulator; EMS memory; Expanded Memory Adapter; EMMQXXX0; EMMXXXQ0; EMM$$$$$; EMS memory tiling; AST RAMpage; AST Research RAMpage; RAMpage; RAMpage!; AST Research RAMpage!; AST RAMpage!; AST RAMpage Plus; AST Research RAMpage Plus; RAMpage Plus; Quadram Quadems+; Quadems+; Limulator; AQA EEMS; IBM XMA; IBM Expanded Memory Adapter; XMA (expanded memory); Emsimulator; Kam & Associates Emsimulator; V-EMM; Fort V-EMM; Fort's V-EMM; Fort's Software V-EMM; Limsim; Larson Limsim; Larson Computing Limsim; Above Disk; Above Disc; Tele-Ware West Above Disk; Tele-Ware West Above Disc; Tele-Ware Above Disk; Tele-Ware Above Disc; Teleware Above Disk; Teleware Above Disc; EMS specification; LIM EMS specification; Lotus/Intel/Microsoft Expanded Memory Specification Version 4.0; Lotus/Intel Expanded Memory Specification Version 3.0; Lotus/Intel/Microsoft Expanded Memory Specification Version 3.2; Lotus/Intel/Microsoft Expanded Memory Specification; EMS Memory Manager; EMM (memory management)
<
storage> (EMS) An
IBM PC memory
paging scheme enabling
access to memory other than
conventional memory in {real
mode}.
Expanded memory is provided through a
page frame of at
least 64
kilobytes in the
reserved memory address region.
Access to this memory is provided by an {
expanded memory
manager} (EMM) software. The EMM functions are accessible
through
interrupt 67H.
In
8086 or
8088 based systems this is the only way to use
memory beyond conventional memory. In systems based on
80286 or later,
XMS and
HMA provide alternative methods.
EMS was developed jointly by
Lotus,
Intel, and
Microsoft
prior to 1988. Accordingly, this specification is sometimes
referred to as LIM EMS.
A complete discussion of EMS and programming examples can be
found in [
"PC System Programming for developers", 1989, ISBN
1-55755-035-2 (Book only) and ISBN 1-55755-036-0 (Book and
diskette)].
EEMS, a competing
expanded memory management standard, was
developed by
AST Research,
Quadram and
Ashton-Tate.
See also
upper memory block.
(1996-01-10)