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Killer Poke
In computer jargon, a killer poke is a method of inducing physical hardware damage on a machine or its peripherals by the insertion of invalid values, via, for example, BASIC's POKE command, into a memory-mapped control register. The term is typically used to describe a family of fairly well known tricks that can overload the analog electronics in the CRT monitors of computers lacking hardware sanity checking (notable examples being the IBM Portable and Commodore PET.) Specific examples Zuse Z1/Z3 The Z1 (1938) and Z3 (1941) computers built by Konrad Zuse contained illegal sequences of instructions which damaged the hardware if executed by accident. Commodore PET The PET-specific killer poke is connected to the architecture of that machine's video rasterizer circuits. In early PETs, writing a certain value to the memory address of a certain I/O register (POKE 59458,62) made the machine able to display text and graphics on the screen 106% faster. This was accomplished by dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Jargon
Jargon is the specialized terminology associated with a particular field or area of activity. Jargon is normally employed in a particular communicative context and may not be well understood outside that context. The context is usually a particular occupation (that is, a certain trade, profession, vernacular or academic field), but any ingroup can have jargon. The main trait that distinguishes jargon from the rest of a language is special vocabulary—including some words specific to it and often different senses or meanings of words, that outgroups would tend to take in another sense—therefore misunderstanding that communication attempt. Jargon is sometimes understood as a form of technical slang and then distinguished from the official terminology used in a particular field of activity. The terms ''jargon'', ''slang,'' and ''argot'' are not consistently differentiated in the literature; different authors interpret these concepts in varying ways. According to one definition, j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burn-in
Burn-in is the process by which components of a system are exercised before being placed in service (and often, before the system being completely assembled from those components). This testing process will force certain failures to occur under supervised conditions so an understanding of load capacity of the product can be established. The intention is to detect those particular components that would fail as a result of the initial, high-failure rate portion of the bathtub curve of component reliability. If the burn-in period is made sufficiently long (and, perhaps, artificially stressful), the system can then be trusted to be mostly free of further early failures once the burn-in process is complete. Theoretically, any weak components would fail during the "Burn In" time allowing those parts to be replaced. Replacing the weak components would prevent premature failure, infant mortality failure, or other latent defects. When the equivalent lifetime of the stress is extended i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBC Micro
The British Broadcasting Corporation Microcomputer System, or BBC Micro, is a series of microcomputers and associated peripherals designed and built by Acorn Computers in the 1980s for the BBC Computer Literacy Project. Designed with an emphasis on education, it was notable for its ruggedness, expandability, and the quality of its operating system. An accompanying 1982 television series, ''The Computer Programme'', featuring Chris Serle learning to use the machine, was broadcast on BBC2. After the Literacy Project's call for bids for a computer to accompany the TV programmes and literature, Acorn won the contract with the ''Proton'', a successor of its Atom computer prototyped at short notice. Renamed the BBC Micro, the system was adopted by most schools in the United Kingdom, changing Acorn's fortunes. It was also successful as a home computer in the UK, despite its high cost. Acorn later employed the machine to simulate and develop the ARM architecture. While nine models ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amstrad CPC
The Amstrad CPC (short for ''Colour Personal Computer'') is a series of 8-bit home computers produced by Amstrad between 1984 and 1990. It was designed to compete in the mid-1980s home computer market dominated by the Commodore 64 and the Sinclair ZX Spectrum, where it successfully established itself primarily in the United Kingdom, France, Spain, and the German-speaking parts of Europe. The series spawned a total of six distinct models: The ''CPC464'', ''CPC664'', and ''CPC6128'' were highly successful competitors in the European home computer market. The later ''464plus'' and ''6128plus'', intended to prolong the system's lifecycle with hardware updates, were considerably less successful, as was the attempt to repackage the ''plus'' hardware into a game console as the ''GX4000''. The CPC models' hardware is based on the Zilog Z80A CPU, complemented with either 64 or 128 KB of RAM. Their computer-in-a-keyboard design prominently features an integrated storage device, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nascom
The Nascom 1 and 2 were single-board computer kits issued in the United Kingdom in 1977 and 1979, respectively, based on the Zilog Z80 and including a keyboard and video interface, a serial port that could be used to store data on a tape cassette using the Kansas City standard, and two 8-bit parallel ports. At that time, including a full keyboard and video display interface was uncommon, as most microcomputer kits were then delivered with only a hexadecimal keypad and seven-segment display. To minimize cost, the buyer had to assemble a Nascom by hand-soldering about 3,000 joints on the single circuit board. Later on, a pre-built, cased machine named Nascom 3 was available; this used the Nascom 2 board. History The history of Nascom starts with the history of John A. Marshall. Marshall was the "& Son" of "A Marshall & Son (London) Ltd", an electronic component retailer whose adverts were a regular feature in hobby electronics magazines from as early as 1967. Marshall was a d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM PCjr
The IBM PCjr (pronounced "PC junior") was a home computer produced and marketed by IBM from March 1984 to May 1985, intended as a lower-cost variant of the IBM PC with hardware capabilities better suited for video games, in order to compete more directly with other home computers such as the Apple II and Commodore 64. It retained the IBM PC's 8088 CPU and BIOS interface, but provided enhanced graphics and sound, ROM cartridge slots, built-in joystick ports, and an infrared wireless keyboard. The PCjr supported expansion via "sidecar" modules, which could be attached to the side of the unit. Despite widespread anticipation, the PCjr was ultimately unsuccessful in the market. It was only partially IBM compatible, limiting support for IBM's software library, its chiclet keyboard was widely criticized for its poor quality, expandability was limited, and it was initially offered with a maximum of of RAM, insufficient for many PC programs. Models The PCjr came in two models: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IBM PC
The IBM Personal Computer (model 5150, commonly known as the IBM PC) is the first microcomputer released in the IBM PC model line and the basis for the IBM PC compatible de facto standard. Released on August 12, 1981, it was created by a team of engineers and designers directed by Don Estridge in Boca Raton, Florida. The machine was based on open architecture and third-party peripherals. Over time, expansion cards and software technology increased to support it. The PC had a substantial influence on the personal computer market. The specifications of the IBM PC became one of the most popular computer design standards in the world. The only significant competition it faced from a non-compatible platform throughout the 1980s was from the Apple Macintosh product line. The majority of modern personal computers are distant descendants of the IBM PC. History Prior to the 1980s, IBM had largely been known as a provider of business computer systems. As the 1980s opened, their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRS-80 Color Computer
The RadioShack TRS-80 Color Computer, later marketed as the Tandy Color Computer and sometimes nicknamed the CoCo, is a line of home computers developed and sold by Tandy Corporation. Despite sharing a name with the earlier TRS-80, the Color Computer is a completely different, incompatible system and a radical departure in design and compatibility with its Motorola 6809E processor rather than the Zilog Z80 earlier models were built around. The Tandy Color Computer line started in 1980 with what is now called the Color Computer 1. It was followed by the Color Computer 2 in 1983, then the Color Computer 3 in 1986. All three models maintain a high level of software and hardware compatibility, with few programs written for an older model being unable to run on the newer ones. The Color Computer 3 was discontinued in 1991. All Color Computer models shipped with Color BASIC, an implementation of Microsoft BASIC, in ROM. Variants of the OS-9 multitasking operating system were availab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Failure Mode
Failure causes are defects in design, process, quality, or part application, which are the underlying cause of a failure or which initiate a process which leads to failure. Where failure depends on the user of the product or process, then human error must be considered. Component failure / failure modes A part failure mode is the way in which a component failed "functionally" on the component level. Often a part has only a few failure modes. For example, a relay may fail to open or close contacts on demand. The failure mechanism that caused this can be of many different kinds, and often multiple factors play a role at the same time. They include corrosion, welding of contacts due to an abnormal electric current, return spring fatigue failure, unintended command failure, dust accumulation and blockage of mechanism, etc. Seldom only one cause (hazard) can be identified that creates system failures. The real root causes can in theory in most cases be traced back to some kind of huma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRS-80 Model III
The TRS-80 Micro Computer System (TRS-80, later renamed the Model I to distinguish it from successors) is a desktop microcomputer launched in 1977 and sold by Tandy Corporation through their Radio Shack stores. The name is an abbreviation of ''Tandy Radio Shack, Z80 icroprocessor'. It is one of the earliest mass-produced and mass-marketed retail home computers. The TRS-80 has a full-stroke QWERTY keyboard, the Zilog Z80 processor, 4 KB dynamic random-access memory (DRAM) standard memory, small size and desk area, floating-point Level I BASIC language interpreter in read-only memory (ROM), 64-character per line video monitor, and a starting price of US$600 (equivalent to US$ in ). A cassette tape drive for program storage was included in the original package. While the software environment was stable, the cassette load/save process combined with keyboard bounce issues and a troublesome Expansion Interface contributed to the Model I's reputation as not well-suited to serious ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore 1571
The Commodore 1571 is Commodore's high-end 5¼" floppy disk drive, announced in the summer of 1985. With its double-sided drive mechanism, it has the ability to use double-sided, double-density (DS/DD) floppy disks, storing a total of 360 kB per floppy. It also implemented a "burst mode" that doubled transfer speeds, helping address the very slow performance of previous Commodore drives. Earlier Commodore drives used a custom group coded recording format that stored 170 kB per side of a disk. This made it fairly competitive in terms of storage, but limited it to only reading and writing disks from other Commodore machines. The 1571 was designed to partner with the new Commodore 128 (C128), which introduced support for CP/M. Adding double-density MFM encoding allowed the drive to read and write contemporary CP/M disks (and many others). In contrast to its single-sided predecessors, the 1541 and the briefly-available 1570, the 1571 can use both sides of the disk a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copy Protection
Copy protection, also known as content protection, copy prevention and copy restriction, describes measures to enforce copyright by preventing the reproduction of software, films, music, and other media. Copy protection is most commonly found on videotapes, DVDs, Blu-ray discs, HD-DVDs, computer software discs, video game discs and cartridges, audio CDs and some VCDs. Some methods of copy protection have also led to criticism because it caused inconvenience for paying consumers or secretly installed additional or unwanted software to detect copying activities on the consumer's computer. Making copy protection effective while protecting consumer rights remains a problem with media publication. Terminology Media corporations have always used the term copy protection, but critics argue that the term tends to sway the public into identifying with the publishers, who favor restriction technologies, rather than with the users. Copy prevention and copy control may be more neutral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
