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Cambridge Z88
The Cambridge Computer Z88 is a Zilog Z80-based portable computer released in 1987 by Cambridge Computer, the company formed for such purpose by Clive Sinclair. It was approximately A4 paper sized and lightweight at , running on four AA batteries for 20 hours of use. It was packaged with a built-in combined word processing/spreadsheet/database application called ''PipeDream'' (functionally equivalent to a 1987 BBC Micro ROM called Acornsoft View Professional), along with several other applications and utilities, such as a Z80-version of the BBC BASIC programming language. History The Z88 evolved from Sir Clive Sinclair's ''Pandora'' portable computer project which had been under development at Sinclair Research during the mid-1980s. Following the sale of Sinclair Research to Amstrad, Sinclair released the Z88 through his Cambridge Computer mail-order company. The machine was launched at the ''Which Computer?'' Show on 17 February 1987. Early models were contract-manufactured ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portable Computer
A portable computer is a computer designed to be easily moved from one place to another and included a display and keyboard together, with a single plug, much like later desktop computers called '' all-in-ones'' (AIO), that integrate the system's internal components into the same case as the display. The first commercially sold portable might be the MCM/70, released 1974. The next major portables were the IBM 5100 (1975), Osborne's CP/M-based Osborne 1 (1981) and Compaq's , advertised as 100% IBM PC compatible Compaq Portable (1983). These luggable computers still required a continuous connection to an external power source; this limitation was later overcome by the laptop. Laptops were followed by lighter models, so that in the 2000s mobile devices and by 2007 smartphones made the term almost meaningless. The 2010s introduced wearable computers such as smartwatches. Portable computers, by their nature, are generally microcomputers. Larger portable computers were commo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinclair Research
Sinclair Research Ltd is a British consumer electronics company founded by Clive Sinclair in Cambridge. It was originally incorporated in 1973 as Westminster Mail Order Ltd, renamed Sinclair Instrument Ltd, then Science of Cambridge Ltd, then Sinclair Computers Ltd, and finally Sinclair Research Ltd. It remained dormant until 1976, when it was activated with the intention of continuing Sinclair's commercial work from his earlier company Sinclair Radionics, and adopted the name Sinclair Research in 1981. In 1980, Clive Sinclair entered the home computer market with the ZX80 at £99.95, at that time the cheapest personal computer for sale in the United Kingdom. In 1982 the ZX Spectrum was released, becoming the UK's best selling computer, and competing aggressively against Commodore and Amstrad. At the height of its success, and largely inspired by the Japanese Fifth Generation Computer program, the company established the "MetaLab" research centre at Milton Hall near Cambrid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battery (electricity)
An electric battery is a source of electric power consisting of one or more electrochemical cells with external connections for powering electrical devices. When a battery is supplying power, its positive terminal is the cathode and its negative terminal is the anode. The terminal marked negative is the source of electrons that will flow through an external electric circuit to the positive terminal. When a battery is connected to an external electric load, a redox reaction converts high-energy reactants to lower-energy products, and the free-energy difference is delivered to the external circuit as electrical energy. Historically the term "battery" specifically referred to a device composed of multiple cells; however, the usage has evolved to include devices composed of a single cell. Primary (single-use or "disposable") batteries are used once and discarded, as the electrode materials are irreversibly changed during discharge; a common example is the alkaline battery used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Keyboard
A membrane keyboard is a computer keyboard whose "keys" are not separate, moving parts, as with the majority of other keyboards, but rather are pressure pads that have only outlines and symbols printed on a flat, flexible surface. Very little, if any, tactile feedback is felt when using such a keyboard. Membrane keyboards work by electrical contact between the keyboard surface and the underlying circuits when keytop areas are pressed. These models were used with some early 1980s home computers, enjoying wide adoption in consumer electronics devices. The keyboards are quite inexpensive to mass-produce, and are more resistant against dirt and liquids than most other keyboards. However, due to a low or non-existent tactile feedback, most people have difficulty typing with them, especially when larger numbers of characters are being typed. Chiclet keyboards were a slight improvement, at least allowing individual keys to be felt to some extent. Aside from early hobbyist/kit/home comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megabyte
The megabyte is a multiple of the unit byte for digital information. Its recommended unit symbol is MB. The unit prefix ''mega'' is a multiplier of (106) in the International System of Units (SI). Therefore, one megabyte is one million bytes of information. This definition has been incorporated into the International System of Quantities. In the computer and information technology fields, other definitions have been used that arose for historical reasons of convenience. A common usage has been to designate one megabyte as (220 B), a quantity that conveniently expresses the binary architecture of digital computer memory. The standards bodies have deprecated this usage of the megabyte in favor of a new set of binary prefixes, in which this quantity is designated by the unit mebibyte (MiB). Definitions The unit megabyte is commonly used for 10002 (one million) bytes or 10242 bytes. The interpretation of using base 1024 originated as technical jargon for the byte SI prefix, mult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operating System
An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting software for cost allocation of processor time, mass storage, printing, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer from cellular phones and video game consoles to web servers and supercomputers. The dominant general-purpose personal computer operating system is Microsoft Windows with a market share of around 74.99%. macOS by Apple Inc. is in second place (14.84%), and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Read-only Memory
Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Read-only memory is useful for storing software that is rarely changed during the life of the system, also known as firmware. Software applications (like video games) for programmable devices can be distributed as plug-in cartridges containing ROM. Strictly speaking, ''read-only memory'' refers to memory that is hard-wired, such as diode matrix or a mask ROM integrated circuit (IC), which cannot be electronically changed after manufacture. Although discrete circuits can be altered in principle, through the addition of bodge wires and/or the removal or replacement of components, ICs cannot. Correction of errors, or updates to the software, require new devices to be manufactured and to replace the installed device. Floating-gate ROM semiconductor memory in the form of erasab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Random-access Memory
Random-access memory (RAM; ) is a form of computer memory that can be read and changed in any order, typically used to store working Data (computing), data and machine code. A Random access, random-access memory device allows data items to be read (computer), read or written in almost the same amount of time irrespective of the physical location of data inside the memory, in contrast with other direct-access data storage media (such as hard disks, CD-RWs, DVD-RWs and the older Magnetic tape data storage, magnetic tapes and drum memory), where the time required to read and write data items varies significantly depending on their physical locations on the recording medium, due to mechanical limitations such as media rotation speeds and arm movement. RAM contains multiplexer, multiplexing and demultiplexing circuitry, to connect the data lines to the addressed storage for reading or writing the entry. Usually more than one bit of storage is accessed by the same address, and RAM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microprocessor
A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circuitry required to perform the functions of a computer's central processing unit. The integrated circuit is capable of interpreting and executing program instructions and performing arithmetic operations. The microprocessor is a multipurpose, clock-driven, register-based, digital integrated circuit that accepts binary data as input, processes it according to instructions stored in its memory, and provides results (also in binary form) as output. Microprocessors contain both combinational logic and sequential digital logic, and operate on numbers and symbols represented in the binary number system. The integration of a whole CPU onto a single or a few integrated circuits using Very-Large-Scale Integration (VLSI) greatly reduced the cost of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CMOS
Complementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss", ) is a type of metal–oxide–semiconductor field-effect transistor (MOSFET) fabrication process that uses complementary and symmetrical pairs of p-type and n-type MOSFETs for logic functions. CMOS technology is used for constructing integrated circuit (IC) chips, including microprocessors, microcontrollers, memory chips (including CMOS BIOS), and other digital logic circuits. CMOS technology is also used for analog circuits such as image sensors (CMOS sensors), data converters, RF circuits (RF CMOS), and highly integrated transceivers for many types of communication. The CMOS process was originally conceived by Frank Wanlass at Fairchild Semiconductor and presented by Wanlass and Chih-Tang Sah at the International Solid-State Circuits Conference in 1963. Wanlass later filed US patent 3,356,858 for CMOS circuitry and it was granted in 1967. commercialized the technology with the trademark "COS-MO ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SCI Systems
SCI may refer to: Companies *Service Corporation International, an American funeral service provider *Shipping Corporation of India *SCI Systems, merged into Sanmina Corporation, electronics manufacturing *SCi Games, a video game developer Organizations and sporting * Safari Club International * Schistosomiasis Control Initiative * Scientific Computing and Imaging Institute * Seamen's Church Institute of New York and New Jersey * Service Civil International, peace movement * Silverthorn Collegiate Institute, school in Toronto, Ontario, Canada * Sister Cities International * Society of Chemical Industry * Solar Cookers International * Sport Club Internacional, a football club in Brazil * Strategic Computing Initiative, US program to fund AI research * Sustainable Commodity Initiative * Systemics, Cybernetics and Informatics, conference later named WMSCI * Southern Careers Institute Science *Metcalf Center for Science and Engineering, Boston University, USA *Science Citation In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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