Conventional memoryIn 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. As memory prices rapidly declined, this design decision became a limitation in the use of large memory capacities until the introduction of operating systems and processors that made it irrelevant.
Upper memory areaIn 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 8088CPU's 1024 KB address space for BIOSROM, Video BIOS, Option ROMs, video RAM, RAM on peripherals, memory-mapped I/O, and obsoleted ROM BASIC.
Bank switchingBank switching is a technique used in computer design to increase the amount of usable memory beyond the amount directly addressable by the processor instructions. It can be used to configure a system differently at different times; for example, a ROM required to start a system from diskette could be switched out when no longer needed. In video game systems, bank switching allowed larger games to be developed for play on existing consoles.
DOS memory managementIn IBM PC compatible computing, DOS memory management refers to software and techniques employed to give applications access to more than 640 kibibytes (640*1024 bytes) (KiB) of "conventional memory". The 640 KiB limit was specific to the IBM PC and close compatibles; other machines running DOS had different limits, for example the Apricot PC could have up to 768 KiB and the Sirius Victor 9000, 896 KiB.Lotus 1-2-3Lotus 1-2-3 is a discontinued spreadsheet program from Lotus Development Corporation (later part of IBM). It was the first killer application of the IBM PC, was hugely popular in the 1980s, and significantly contributed to the success of IBM PC-compatibles in the business market. The first spreadsheet program, VisiCalc, had helped launch the Apple II as one of the earliest personal computers in business use.
MicrosoftMicrosoft Corporation is an American multinational technology company headquartered in Redmond, Washington. The company became influential in the rise of personal computers through software like Windows and has since expanded into areas such as Internet services, cloud computing, artificial intelligence, video gaming, and more.
IntelAmerican multinational technology companyIntel Corporation is an American multinational technology company headquartered in Santa Clara, California. It designs, manufactures, and sells computer components such as central processing units (CPUs) and related products for business and consumer markets.
Lotus DevelopmentLotus Development Corporation was an American software company based in Massachusetts. Lotus is best known for the Lotus 1-2-3spreadsheet application, the first feature-heavy, user-friendly, reliable, and WYSIWYG-enabled product to become available in the early days of the IBM PC. It became that platform's killer application and is widely considered one of the reasons the PC became successful.
Ashton-TateAmerican software company Ashton-Tate CorporationIndustrySoftwareFoundedAugust 1980; 46 years ago (1980-08)FounderGeorge Tate, Hal LashleeDefunctOctober 1991; 34 years ago (1991-10)FateAcquiredSuccessorBorlandHeadquarters Torrance, California, USProductsdBASE, Framework, MultiMate, InterBase, RapidFile, and moreNumber of employees1,750 Ashton-Tate Corporation was a US-based software company best known for developing the dBASE database application and later acquiring Framework from the Forefront Corporation and MultiMate from Multimate International.
AST ResearchAST Research, Inc., later doing business asAST Computer, was an American personal computer manufacturer. It was founded in 1980 in Irvine, California, by Albert Wong, Safi Qureshey, and Thomas Yuen, as an initialism of their first names. Wong left the company nine years later, followed by Yuen in 1992, with Qureshey remaining until AST was acquired by Samsung Electronics in 1997. The company began by making a circuit board for the IBM PC that boosted its memory storage.
DOSDOS (, ) is a family of disk-based operating systems for IBM PC compatible computers. It primarily consists of IBM PC DOS and a rebranded version, Microsoft's MS-DOS, both of which were introduced in 1981. Later, compatible systems from other manufacturers are DR-DOS (1988), ROM-DOS (1989), PTS-DOS (1993), and FreeDOS (1994). MS-DOS dominated the IBM PC compatible market between 1981 and 1995.
CoreCard CorporationCoreCard Corporation is an American financial technology company based in Norcross, Georgia. Before 2021, it was named Intelligent Systems Corporation and once sold portable computers, video terminals, expansion cards, and other peripherals through a variety of manufacturing subsidiaries. Founded in 1973, the firm restructured as a master limited partnership in 1987, becoming Intelligent Systems Master Limited Partnership.*As an Amazon Associate I earn from qualifying purchases.