The Cambridge Computer Z88 is a

Zilog Z80 The Z80 is an 8-bit microprocessor introduced by Zilog as the startup company's first product. The Z80 was conceived by Federico Faggin in late 1974 and developed by him and his 11 employees starting in early 1975. The first working samples were ...

-based

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 s ...

released in 1987 by

Cambridge Computer 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 ...

, the company formed for such purpose by Clive Sinclair. It was approximately A4 paper sized and lightweight at , running on four

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for 20 hours of use. It was packaged with a built-in combined

word processing A word is a basic element of language that carries an objective or practical meaning, can be used on its own, and is uninterruptible. Despite the fact that language speakers often have an intuitive grasp of what a word is, there is no conse ...

spreadsheet A spreadsheet is a computer application for computation, organization, analysis and storage of data in tabular form. Spreadsheets were developed as computerized analogs of paper accounting worksheets. The program operates on data entered in c ...

database In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases s ...

application called ''PipeDream'' (functionally equivalent to a 1987

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 emphas ...

ROM called Acornsoft View Professional), along with several other

applications Application may refer to: Mathematics and computing * Application software, computer software designed to help the user to perform specific tasks ** Application layer, an abstraction layer that specifies protocols and interface methods used in a c ...

and utilities, such as a Z80-version of the

BBC BASIC BBC BASIC is a version of the BASIC programming language released in 1981 as the native programming language for the BBC Micro home/personal computer, providing a standardized language for a UK computer literacy project of the BBC. It was wr ...

programming language A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language. The description of a programming ...

History

The Z88 evolved from Sir Clive Sinclair's ''Pandora'' portable computer project which had been under development at

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 ...

during the mid-1980s. Following the sale of Sinclair Research to

Amstrad Amstrad was a British electronics company, founded in 1968 by Alan Sugar at the age of 21. The name is a contraction of Alan Michael Sugar Trading. It was first listed on the London Stock Exchange in April 1980. During the late 1980s, Amstra ...

, Sinclair released the Z88 through his

mail-order company. The machine was launched at the ''Which Computer?'' Show on 17 February 1987. Early models were contract-manufactured by

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but production later switched to SCI Systems in Irvine, Scotland.

Design

The 8-line LCD display used by the Z88 The Z88 is a portable computer weighing , based on a low-power CMOS version of the popular

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 circ ...

. It comes with 32 kB of internal pseudo-static

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and 128 kB of ROM containing the

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 i ...

(called ''OZ''). The memory can be expanded up to 3.5 MB of RAM, the contents of which are preserved across sessions. An integrated capacitor prevents the Z88 from losing its data for the limited time it takes to change the batteries. The machine uses a

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, ...

, which is almost silent in use; an optional electronic "click" can be turned on to indicate keystrokes. The Z88 is powered by four

, giving up to 20 hours of use. It has three memory card slots, which accommodate proprietary RAM,

EPROM An EPROM (rarely EROM), or erasable programmable read-only memory, is a type of programmable read-only memory (PROM) chip that retains its data when its power supply is switched off. Computer memory that can retrieve stored data after a power s ...

or flash cards, the third slot being equipped with a built-in EPROM programmer. Card capacities range from 32 kB to 1 MB. The Z88 has a built-in eight-line, 64 × 640 pixel super-twisted nematic display which has greater contrast than conventional twisted nematic LCDs. The 64 kB addressable by the Z80 processor are divided in four banks of 16 kB each. The maximum memory of 4 MiB for the system is also divided in 256 segments of 16 kB each. The hardware can map any of the 16 kB blocks to any of the four banks. The first 512 kB are reserved for ROM; the next 512 kB are reserved for internal RAM. The next 3 MB are assigned to each one of the three memory slots.

Postmarket upgrades

The stand and port of the Cambridge Z88 Since 1998, a 1 MiB Flash memory card is available which provides convenient non-volatile storage. Once written to the card, files are safe and not reliant on a power supply. Unlike traditional EPROM cards (erased with an external

ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation ...

light), this one can be electrically erased in the computer's slot. The first generation of card only worked in slot 3 where a 12 V signal (Vpp) is available. The later generation is based on

AMD Advanced Micro Devices, Inc. (AMD) is an American multinational semiconductor company based in Santa Clara, California, that develops computer processors and related technologies for business and consumer markets. While it initially manufactur ...

chips and runs with 5 V for erasure. It is possible to read, write and erase flash cards in the three slots and the internal one. It is also possible for an experienced user to replace the built-in 32 kB RAM chip with a bigger 128 or 512 kB static RAM chip. However, the latter requires some extra board modifications, and 512 kB is the biggest size that can be addressed by the Z88 for the internal RAM. A similar modification is possible for the internal ROM slot. A 512 kB flash chip can replace the original ROM, allowing an upgrade of the operating system.

References

External links

Rick Dickinson's "Pandora to Z88" gallery on Flickr

Z88 Forever enthusiast site

New home for the above algonet.se pages

Z88 review, 1989
{{Sinclair computers and clones Computer-related introductions in 1987 Z80-based home computers Home computers Z88 Products introduced in 1987 Portable computers

History

Design

Postmarket upgrades

See also

References

External links