Kempston Micro Electronics was an electronics company based in

Kempston Kempston is a town and civil parish in the Borough of Bedford, Bedfordshire, England. It had a population of 19,330 in the 2011 census. Kempston is part of Bedford's built-up area and is situated directly south-west of Bedford proper. The River ...

Bedfordshire Bedfordshire (; abbreviated Beds) is a ceremonial county in the East of England. The county has been administered by three unitary authorities, Borough of Bedford, Central Bedfordshire and Borough of Luton, since Bedfordshire County Council wa ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

specialising in computer

joystick A joystick, sometimes called a flight stick, is an input device consisting of a stick that pivots on a base and reports its angle or direction to the device it is controlling. A joystick, also known as the control column, is the principal cont ...

s and related home computer peripherals during the 1980s. The Kempston Interface, a

peripheral A peripheral or peripheral device is an auxiliary device used to put information into and get information out of a computer. The term ''peripheral device'' refers to all hardware components that are attached to a computer and are controlled by the ...

which allowed a joystick using the ''de facto''

Atari joystick port The Atari joystick port is a computer port used to connect various gaming controllers to game console and home computer systems in the 1970s to the 1990s. It was originally introduced on the Atari 2600 in 1977 and then used on the Atari 400 an ...

standard to be connected to the

ZX Spectrum The ZX Spectrum () is an 8-bit computing, 8-bit home computer that was developed by Sinclair Research. It was released in the United Kingdom on 23 April 1982, and became Britain's best-selling microcomputer. Referred to during development as t ...

, was one of the most widely used add-ons to the machine.

Interface

Kempston joystick interface Kempston Interface plugged into a Spectrum Plus ZX Spectrum KempstonJoyInterface

The Kempston Interface is a

interface used on the

Sinclair ZX Spectrum The ZX Spectrum () is an 8-bit home computer that was developed by Sinclair Research. It was released in the United Kingdom on 23 April 1982, and became Britain's best-selling microcomputer. Referred to during development as the ''ZX81 Colour ...

series of computers that allows controllers complying with the ''de facto''

standard (using the

DE-9 connector The D-subminiature or D-sub is a common type of electrical connector. They are named for their characteristic D-shaped metal shield. When they were introduced, D-subs were among the smallest connectors used on computer systems. Description, no ...

) to be used with the machine. The interface itself would be attached to the computer's rear expansion port with a single joystick port on the front or top of the system. Apart from implementing existing joystick interfacing modes they produced their own standard which delivered the joystick state on the Z80 bus at port 31 (read in BASIC using IN 31). This meant that the joystick did not produce key-presses like the other standards, such as ''Cursor'', and the method was soon borrowed by other interface manufacturers and became quite popular. It was one of the most widely supported standards on the machine, coming out as the clear winner against other standards such as Protek and AGF's cursor-based solution and the Fuller standard during the days of the 48K Spectrum. When

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, Amstrad ...

released the

ZX Spectrum +2 ZX may refer to: Arts and entertainment * Kamen Rider ZX (pronounced "Zed-Cross"), the tenth fictional superhero in the "Kamen Rider" franchise * ''Mega Man ZX'', a video game for the Nintendo DS * ''ZX Tunes'', remastered soundtracks of the "Meg ...

, the computer featured a built-in joystick interface that was software-compatible with Sinclair's ZX Interface 2 standard. However, the bundled ''SJS-1'' joystick was electrically incompatible with the Atari standard. The Interface 2 standard simulated keypresses on the numerical keys ( to and to being left, right, down, up, fire for the 'left' and 'right' joysticks respectively) and hence were ideal for games with no official joystick support but in which the keys could be redefined. Inserting or removing the joystick interface when the computer was turned on was inadvisable as it would almost certainly damage the computer hardware.

Mouse

* x-axis at port 64479 * y-axis at port 65503 * two buttons at port 64223

Joysticks

The Formula 1 was based on the Quickshot 1 and released June 1985. The Score Board features a base similar in size to a 48K Spectrum, with two fire buttons. Released June 1985. The Competition Pro consisted of a square base, two large red buttons (for left or right-handed use) and a black pommel stick. It used the

Atari 2600 The Atari 2600, initially branded as the Atari Video Computer System (Atari VCS) from its release until November 1982, is a home video game console developed and produced by Atari, Inc. Released in September 1977, it popularized microprocessor- ...

standard

DE-9 The D-subminiature or D-sub is a common type of electrical connector. They are named for their characteristic D-shaped metal shield. When they were introduced, D-subs were among the smallest connectors used on computer systems. Description, n ...

connector and was primary designed to work with the

Kempston joystick interface but also with the compatible ports built into other home computers such as the

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 Sin ...

Commodore 64 The Commodore 64, also known as the C64, is an 8-bit home computer introduced in January 1982 by Commodore International (first shown at the Consumer Electronics Show, January 7–10, 1982, in Las Vegas). It has been listed in the Guinness ...

VIC-20 The VIC-20 (known as the VC-20 in Germany and the VIC-1001 in Japan) is an 8-bit home computer that was sold by Commodore Business Machines. The VIC-20 was announced in 1980, roughly three years after Commodore's first personal computer, the PE ...

) and later

Commodore Amiga Amiga is a family of personal computers introduced by Commodore in 1985. The original model is one of a number of mid-1980s computers with 16- or 32-bit processors, 256 KB or more of RAM, mouse-based GUIs, and significantly improved graphi ...

and

Atari ST The Atari ST is a line of personal computers from Atari Corporation and the successor to the Atari 8-bit family. The initial model, the Atari 520ST, had limited release in April–June 1985 and was widely available in July. It was the first pers ...

. There was also an

Atari 5200 The Atari 5200 SuperSystem or simply Atari 5200 is a home video game console introduced in 1982 by Atari, Inc. as a higher-end complement for the popular Atari Video Computer System. The VCS was renamed to the Atari 2600 at the time of the 5200' ...

model which leveraged the existing CX52 controller for the keypad functionality.

References

{{Use dmy dates, date=October 2019 Defunct manufacturing companies of the United Kingdom Home computer hardware companies Game controllers ZX Spectrum Electronics companies of the United Kingdom Kempston Companies based in Bedfordshire