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NIOS (NetWare)
DOS Protected Mode Services (DPMS) is a set of extended DOS memory management services to allow DPMS-enabled DOS drivers to load and execute in extended memory and protected mode. Not being a DOS extender by itself, DPMS is a minimal set of extended DOS memory management services to allow slightly modified DOS resident system extensions ( RSX) such as device drivers or TSRs (as so called ''DPMS clients'') to relocate themselves into extended memory and run in 16-bit or 32-bit protected mode while leaving only a tiny stub in conventional memory as an interface to communicate with the conventional DOS environment. The DPMS clients do so through DPMS services provided by a previously loaded ''DPMS server''. The necessary size of the remaining stub depends on the type of driver, but often can be reduced to a few hundred bytes for just the header even for complex drivers. By executing the driver in extended memory and freeing up conventional memory, DPMS not only allows very lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extended Memory
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Windows 9x
Windows 9x is a generic term referring to a series of Microsoft Windows computer operating systems produced from 1995 to 2000, which were based on the Windows 95 kernel and its underlying foundation of MS-DOS, both of which were updated in subsequent versions. The first version in the 9x series was Windows 95, which was succeeded by Windows 98 and then Windows Me, which was the third and last version of Windows on the 9x line, until the series was superseded by Windows XP. Windows 9x is predominantly known for its use in home desktops. In 1998, Windows made up 82% of operating system market share. Internal release versions for versions of Windows 9x are 4.x. The internal versions for Windows 95, 98, and Me are 4.0, 4.1, and 4.9, respectively. Previous MS-DOS-based versions of Windows used version numbers of 3.2 or lower. Windows NT, which was aimed at professional users such as networks and businesses, used a similar but separate version number between 3.1 and 4.0. All versi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DR DOS "Panther"
DR-DOS (written as DR DOS, without a hyphen, in versions up to and including 6.0) is a disk operating system for IBM PC compatibles. Upon its introduction in 1988, it was the first DOS attempting to be compatible with IBM PC DOS and MS-DOS (which were the same product sold under different names). DR-DOS was developed by Gary A. Kildall's Digital Research and derived from Concurrent PC DOS 6.0, which was an advanced successor of CP/M-86. As ownership changed, various later versions were produced with names including Novell DOS and Caldera OpenDOS. History Origins in CP/M Digital Research's original CP/M for the 8-bit Intel 8080- and Z-80-based systems spawned numerous spin-off versions, most notably CP/M-86 for the Intel 8086/8088 family of processors. Although CP/M had dominated the market since the mid-1970s, and was shipped with the vast majority of non-proprietary-architecture personal computers, the IBM PC in 1981 brought the beginning of what was eventua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extended Memory Specification
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) meth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel 80386
The Intel 386, originally released as 80386 and later renamed i386, is a 32-bit microprocessor introduced in 1985. The first versions had 275,000 transistorsmit.edu—The Future of FPGAs (Cornell) October 11, 2012 and were the CPU of many s and high-end s of the time. As the original implementation of the |
Intel 80286
The Intel 80286 (also marketed as the iAPX 286 and often called Intel 286) is a 16-bit microprocessor that was introduced on February 1, 1982. It was the first 8086-based CPU with separate, non-multiplexed address and data buses and also the first with memory management and wide protection abilities. The 80286 used approximately 134,000 transistors in its original nMOS (HMOS) incarnation and, just like the contemporary 80186, it could correctly execute most software written for the earlier Intel 8086 and 8088 processors. The 80286 was employed for the IBM PC/AT, introduced in 1984, and then widely used in most PC/AT compatible computers until the early 1990s. In 1987, Intel shipped its five-millionth 80286 microprocessor. History and performance Intel's first 80286 chips were specified for a maximum clockrate of 5, 6 or 8 MHz and later releases for 12.5 MHz. AMD and Harris later produced 16 MHz, 20 MHz and 25 MHz parts, respectively. Intersil and Fuj ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Memory Block
In DOS memory management, the upper memory area (UMA) refers to computer memory, memory between the address space, addresses of 640 Kilobyte, KB and 1024 KB (Hexadecimal, 0xA0000–0xFFFFF) in an IBM PC or compatible. IBM reserved the uppermost 384 KB of the Intel 8088, 8088 Central processing unit, 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 BASIC. However, even with video RAM, the ROM BIOS, the Video BIOS, the Option ROMs, and I/O ports for peripherals, much of this 384 KB of address space was unused. As the 640 KB memory restriction became ever more of an obstacle, techniques were found to fill the empty areas with RAM. These areas were referred to as upper memory blocks (UMBs). Usage The next stage in the evolution of DOS was for the operating system to use upper memory blocks (UMBs) and the high memory area (HMA). This occurred with the release of DR ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SoftICE
SoftICE is a kernel mode debugger for DOS and Windows up to Windows XP. It is designed to run underneath Windows, so that the operating system is unaware of its presence. Unlike an application debugger, SoftICE is capable of suspending all operations in Windows when instructed. Because of its low-level capabilities, SoftICE is also popular as a software cracking tool. Microsoft offers two kernel-mode debuggers, WinDbg and KD, without charges. However, the full capabilities of WinDbg and KD are available only when two interlinked computers are used. SoftICE, therefore, is an exceptionally useful tool for difficult driver related development. The last released version was for Windows XP. Older versions exist for DOS and compatible operating systems. SoftICE was originally produced by a company called NuMega, and was subsequently acquired by Compuware in 1997, which in turn sold the property to Micro Focus in 2009. Currently, Micro Focus owns the source code and patents, but is no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NuMega
NuMega Technologies, Inc. (also known as NuMega), was a software company founded in 1987 by Frank Grossman and Jim Moskun in Nashua, New Hampshire. The company developed a Kernel mode debugger, now SoftICE, for DOS and the Windows NT family.Mark Russinovich o#64Podnutz (2:00/1:03:09)/ref> In 1995, the company acquired the Marquis Computing, Inc. assets VB/CodeReview and VB/FailSafe, and hired its president, Hank Marquis to manage NuMega Visual Basic products. In December 1997, the company was acquired by Compuware, when it became NuMega Labs of Compuware. Less than a year after moving to Merrimack, the development lab was effectively shut down on 11 June 2007. In June 2009, Compuware sold the former NuMega products, the intellectual property and transferred the remaining staff to a UK-based firm named Micro Focus. Mark Russinovich, a software developer who now serves as CTO of Microsoft Azure, started his career at NuMega. Hank Marquis, who served as a Leadership Partner at Gar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ring 0 (computer Security)
In computer science, hierarchical protection domains, often called protection rings, are mechanisms to protect data and functionality from faults (by improving fault tolerance) and malicious behavior (by providing computer security). Computer operating systems provide different levels of access to resources. A protection ring is one of two or more hierarchical ''levels'' or ''layers'' of privilege within the architecture of a computer system. This is generally hardware-enforced by some CPU architectures that provide different CPU modes at the hardware or microcode level. Rings are arranged in a hierarchy from most privileged (most trusted, usually numbered zero) to least privileged (least trusted, usually with the highest ring number). Ring 0 is the level with the most privileges and allows direct interaction with the physical hardware such as certain CPU functionality and chips on the motherboard. Special call gates between rings are provided to allow an outer ring to acc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ring 1 (computer Security)
In computer science, hierarchical protection domains, often called protection rings, are mechanisms to protect data and functionality from faults (by improving fault tolerance) and malicious behavior (by providing computer security). Computer operating systems provide different levels of access to resources. A protection ring is one of two or more hierarchical ''levels'' or ''layers'' of privilege within the architecture of a computer system. This is generally hardware-enforced by some CPU architectures that provide different CPU modes at the hardware or microcode level. Rings are arranged in a hierarchy from most privileged (most trusted, usually numbered zero) to least privileged (least trusted, usually with the highest ring number). Ring 0 is the level with the most privileges and allows direct interaction with the physical hardware such as certain CPU functionality and chips on the motherboard. Special call gates between rings are provided to allow an outer ring to acc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EMM386
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 which is used to create expanded memory using extended memory on Intel 80386 CPUs. There also is an EMM386.EXE available in FreeDOS. Overview EMM386.EXE can map memory into unused blocks in the upper memory area (UMA), allowing device drivers and TSRs to be "loaded high", preserving conventional memory. The technique probably first appeared with the development of CEMM, included with Compaq MS-DOS 3.31 in 1987. Microsoft's version first appeared, built-in, with Windows/386 2.1 in 1988 and as standalone EMM386.SYS with MS-DOS 4.01 in 1989; the more flexible EMM386.EXE version appeared in MS-DOS 5.0 in 1991. Just as the other expanded memory managers, EMM386 uses the processor's virtual 8086 mode. This forces memory accesses made by DOS applications to go through the processor's MMU (introduced in the 386), and the page table entries used by the MMU are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
