Search results
Results from the WOW.Com Content Network
IBM, however, created its own expanded-memory standard called XMA. The use of expanded memory became common with games and business programs such as Lotus 1-2-3 in the late 1980s through the mid-1990s, but its use declined as users switched from DOS to protected-mode operating systems such as Linux, IBM OS/2, and Microsoft Windows.
Extended memory is located above 1 MB, includes the high memory area, and ends at 16 MB on the Intel 286 and at 4 GB on the Intel 386DX and later.. In DOS memory management, extended memory refers to memory above the first megabyte (2 20 bytes) of address space in an IBM PC or compatible with an 80286 or later processor.
EMM386 is the expanded memory manager of Microsoft's MS-DOS, IBM's PC DOS, Digital Research's DR-DOS, and Datalight's ROM-DOS [1] which is used to create expanded memory using extended memory on Intel 80386 CPUs. There also is an EMM386.EXE available in FreeDOS. [2]
For the IBM PC and IBM PC/XT, with only 20 address lines, special-purpose expanded memory cards were made containing perhaps a megabyte, or more, of expanded memory, with logic on the board to make that memory accessible to the processor in defined parts of the 8088 address space.
Traditionally IBM Mainframe memory has been byte-addressable. This kind of memory is termed "Central Storage". IBM Mainframe processors through much of the 1980s and 1990s supported another kind of memory: Expanded Storage. It was first introduced with the IBM 3090 high-end mainframe series in 1985. [24] Expanded Storage is 4KB-page addressable.
Expanded memory in the IBM PC. In 1985, the companies Lotus and Intel introduced Expanded Memory Specification (EMS) 3.0 for use in IBM PC compatible computers running MS-DOS. Microsoft joined for versions 3.2 in 1986 and 4.0 in 1987 and the specification became known as Lotus-Intel-Microsoft EMS or LIM EMS.
Memory areas of the IBM PC family. In DOS memory management, conventional memory, also called base memory, is the first 640 kilobytes of the memory on IBM PC or compatible systems. It is the read-write memory directly addressable by the processor for use by the operating system and application programs.
In DOS memory management, the upper memory area (UMA) is the memory between the addresses of 640 KB and 1024 KB (0xA0000–0xFFFFF) in an IBM PC or compatible. IBM reserved the uppermost 384 KB of the 8088 CPU 's 1024 KB address space for BIOS ROM , Video BIOS , Option ROMs , video RAM, RAM on peripherals, memory-mapped I/O , and obsoleted ROM ...