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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 (220 bytes) of address space in an IBM PC or compatible with an 80286 or later processor. The term is mainly used under the DOS and Windows operating systems. DOS programs, running in real mode or virtual x86 mode, cannot directly access this memory, but are able to do so through an application programming interface called the Extended Memory Specification (XMS). This API is implemented by a driver (such as HIMEM.SYS) or the operating system, which takes care of memory management and copying memory between conventional and extended memory, by temporarily switching the processor into protected mode. In this context, the term "extended memory" may refer to either the whole of the extended memory or only the portion available through this API.
Extended memory can also be accessed directly by DOS programs running in protected mode using VCPI or DPMI, two (different and incompatible) methods of using protected mode under DOS.
Extended memory should not be confused with expanded memory (EMS), an earlier method for expanding the IBM PC's memory capacity beyond 640 kB (655,360 bytes) using an expansion card with bank switched memory modules. Because of the available support for expanded memory in popular applications, device drivers were developed that emulated expanded memory using extended memory. Later two additional methods were developed allowing direct access to a small portion of extended memory from real mode. These memory areas are referred to as the high memory area (HMA) and the upper memory area (UMA; also referred to as upper memory blocks or UMBs).
In DOS memory management, extendedmemory refers to memory above the first megabyte (220 bytes) of address space in an IBM PC or compatible with an 80286...
memory), upper memory, high memory (not the same as upper memory), extendedmemory, and expanded memory, all handled in different ways. The Intel 8088 processor...
x86 microprocessors with Streaming SIMD Extensions Extendedmemory manager, in the ExtendedMemory Specification Intel XMM modems, in mobile devices Search...
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...
Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time...
boards could be addressed both using an expanded memory model and as extendedmemory. The expanded memory hardware interface used by XMA boards is, however...
format extendedmemory area; an addressable region of memory under a DOS Extender Expanded Memory Adapter, an IBM standard for XT-era expanded memory XMA...
supports 384 KB of extended memory, and the RSX is a fully AT-class machine which can support up to 9 MB of extendedmemory. With the exception of the...
The Memory Stick is a removable flash memory card format, originally launched by Sony in late 1998. In addition to the original Memory Stick, this family...
to and from extendedmemory, access to the 65,520-byte high memory area directly above the first megabyte of memory and the upper memory block area. Generally...
conventional memory by self-relocating resident drivers which move most of themselves into upper memory, the high memory area, expanded or extendedmemory as well...
Eidetic memory (/aɪˈdɛtɪk/ eye-DET-ik), also known as photographic memory and total recall, is the ability to recall an image from memory with high precision—at...
system may extend these capabilities, utilizing, e.g., disk storage, to provide a virtual address space that can exceed the capacity of real memory and thus...
The Socket G3 MemoryExtender (G3MX) was a planned Advanced Micro Devices' solution to the problem of connecting large amounts of memory to a single microprocessor...
terms RAM, main memory, or primary storage. Archaic synonyms for main memory include core (for magnetic core memory) and store. Main memory operates at a...
other extended ASCII encodings (more than 220 DOS and Windows codepages). EBCDIC ("the other" major character code) likewise developed many extended variants...
formulas. Some models have the ability to extendmemory capacity to store more numbers; the extendedmemory address is termed an array index. Power sources...
to run in extendedmemory. In parallel, Intel was working with manufacturers of multitasking environments, EMS emulators, and DOS extenders to ensure...
expanded memory can be emulated using extendedmemory so this method of providing upper memory blocks is usually provided by the expanded memory manager...
AST Officially Endorse Microsoft's ExtendedMemory Spec, InfoWorld, October 3, 1988 Tutor: Expanded vs. extendedmemory, PC Magazine, December 26, 1989,...
multitask several DOS programs and the paged memory model to emulate expanded memory using available extendedmemory. Windows/286, in spite of its name, runs...
philosophy of mind, the extended mind thesis says that the mind does not exclusively reside in the brain or even the body, but extends into the physical world...
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