The Cambridge Z88 is a

Z80 The Zilog Z80 is an 8-bit microprocessor designed by Zilog that played an important role in the evolution of early personal computing. Launched in 1976, it was designed to be software-compatible with the Intel 8080, offering a compelling altern ...

-based

notebook computer A notebook computer or notebook is, historically, a laptop whose length and width approximate that of letter paper (). The term ''notebook'' was coined to describe slab-like portable computers that had a letter-paper footprint, such as Epson's ...

released in 1987 by Cambridge Computer, the company formed for this purpose by

Clive Sinclair Sir Clive Marles Sinclair (30 July 1940 – 16 September 2021) was an English entrepreneur and inventor, best known for being a pioneer in the computing industry and also as the founder of several companies that developed consumer electronics ...

. It was approximately

A4 paper size ISO 216 is an international standard for paper sizes, used around the world except in North America and parts of Latin America. The standard defines the "A", "B" and "C" series of paper sizes, which includes the A4, the most commonly available ...

d and lightweight at , running on four

AA batteries The AA battery (or double-A battery) is a standard size single cell cylindrical dry battery. ANSI and IEC battery nomenclature gives several designations for cells in this size, depending on cell features and chemistry. The IEC 60086 system c ...

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

word processing A word processor (WP) is a device or computer program that provides for input, editing, formatting, and output of text, often with some additional features. Word processor (electronic device), Early word processors were stand-alone devices dedicate ...

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 or a type of data store based on the use of a database management system (DBMS), the software that interacts with end users, applications, and the database itself to capture and a ...

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

BBC Micro The BBC Microcomputer System, or BBC Micro, is a family of microcomputers developed and manufactured by Acorn Computers in the early 1980s as part of the BBC's Computer Literacy Project. Launched in December 1981, it was showcased across severa ...

ROM called

Acornsoft Acornsoft was the software arm of Acorn Computers, and a major publisher of software for the BBC Micro and Acorn Electron. As well as games, it also produced a large number of educational titles, extra computer languages and business and util ...

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 ...

and utilities, such as a Z80-version of the

BBC BASIC BBC BASIC is an interpreted version of the BASIC programming language. It was developed by Acorn Computers Ltd when they were selected by the BBC to supply the computer for their BBC Literacy Project in 1981. It was originally supplied on ...

programming language A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually def ...

History

The Z88 evolved from Sir

'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 in the 1970s. In 1980, the company entered the home computer market with the ZX80 at £99.95, at that time the cheapest personal computer ...

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

Amstrad Amstrad plc was a British consumer electronics company, founded in 1968 by Alan Sugar. During the 1980s, the company was known for its Home computer, home computers beginning with the Amstrad CPC and later also the ZX Spectrum range after the ...

, Sinclair released the Z88 through his Cambridge Computer mail-order company, as he was no longer permitted to use the Sinclair name after the sale. The machine was launched at the ''Which Computer?'' Show on 17 February 1987. Early models were contract-manufactured by

Thorn EMI Thorn EMI was a major British company involved in consumer electronics, music, defence and retail. Created when Thorn Electrical Industries merged with EMI in October 1979, it was listed on the London Stock Exchange and was once a constituen ...

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

Design

The 8-line LCD display used by the Z88 The Z88 is a notebook computer weighing , based on a low-power

CMOS Complementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss ", , ) is a type of MOSFET, metal–oxide–semiconductor field-effect transistor (MOSFET) semiconductor device fabrication, fabrication process that uses complementary an ...

version of the popular

Zilog Z80 The Zilog Z80 is an 8-bit computing, 8-bit microprocessor designed by Zilog that played an important role in the evolution of early personal computing. Launched in 1976, it was designed to be Backward compatibility, software-compatible with the ...

microprocessor A microprocessor is a computer processor (computing), processor for which the data processing logic and control is included on a single integrated circuit (IC), or a small number of ICs. The microprocessor contains the arithmetic, logic, a ...

. It comes with 32 kB of internal pseudo-static

RAM Ram, ram, or RAM most commonly refers to: * A male sheep * Random-access memory, computer memory * Ram Trucks, US, since 2009 ** List of vehicles named Dodge Ram, trucks and vans ** Ram Pickup, produced by Ram Trucks Ram, ram, or RAM may also ref ...

and 128 kB of

ROM Rom, or ROM may refer to: Biomechanics and medicine * Risk of mortality, a medical classification to estimate the likelihood of death for a patient * Rupture of membranes, a term used during pregnancy to describe a rupture of the amniotic sac * ...

containing the

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

(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 tacti ...

, 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) integrated circuit, chip that retains its data when its power supply is switched off. Computer memory that can retrieve stored d ...

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 An STN (super-twisted nematic) display is a type of liquid-crystal display (LCD). An LCD is a flat-panel display that uses liquid crystals to change its properties when exposed to an electric field, which can be used to create images. This change ...

which has greater contrast than conventional

twisted nematic The twisted nematic effect (''TN effect'') was a major technological breakthrough that made the manufacture of large, thin liquid crystal displays practical and cost competitive. Unlike earlier flat-panel displays, TN cells did not require a curre ...

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 The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable un ...

flash memory Flash memory is an Integrated circuit, electronic Non-volatile memory, non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for t ...

card has been available which provides convenient

non-volatile Non-volatile memory (NVM) or non-volatile storage is a type of computer memory that can retain stored information even after power is removed. In contrast, volatile memory needs constant power in order to retain data. Non-volatile memory typ ...

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 radiation, also known as simply UV, is electromagnetic radiation of wavelengths of 10–400 nanometers, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight and constitutes about 10% of ...

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 corporation and technology company headquartered in Santa Clara, California and maintains significant operations in Austin, Texas. AMD is a hardware and fabless company that de ...

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 Static random-access memory (static RAM or SRAM) is a type of random-access memory (RAM) that uses latching circuitry (flip-flop) to store each bit. SRAM is volatile memory; data is lost when power is removed. The ''static'' qualifier differ ...

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.

Reception

Jerry Pournelle Jerry Eugene Pournelle (; August 7, 1933 – September 8, 2017) was an American scientist in the area of operations research and ergonomics, human factors research, a science fiction writer, essayist, journalist, and one of the first bloggers. ...

in February 1989 described the Z88 as "the most portable computer I've ever seen", much more so than his

Zenith SupersPort The SupersPort is a line of IBM PC compatible, PC-compatible laptops manufactured by Zenith Data Systems and sold from 1988 to 1993. The first two main entries in the SupersPort line included either an Intel 80286 microprocessor clocked at 12&nb ...

286. He said that the screen was small but readable, and thought that his $894 estimate for a minimum configuration was "not a ''lot'' of money for good hardware". Pournelle said that Pipedream was "disappointingly hard to use", reported that all of his notes in the software from COMDEX had vanished because he did not explicitly save them to memory card, and suggested that the Z88 was best suited as a second computer for students and reporters.

References

External links