{"id":39456,"date":"2026-02-13T20:00:00","date_gmt":"2026-02-13T19:00:00","guid":{"rendered":"https:\/\/www.jungsi.de\/?p=39456"},"modified":"2026-03-14T12:12:23","modified_gmt":"2026-03-14T11:12:23","slug":"kempston-joystick-interface-sinclair-zx-spectrum","status":"publish","type":"post","link":"https:\/\/www.jungsi.de\/en\/kempston-joystick-interface-sinclair-zx-spectrum\/","title":{"rendered":"Kempston Joystick Interface"},"content":{"rendered":"<p class=\"wp-block-paragraph\"><strong>Kempston Joystick Interface (1983) \u2013 the standard that gave the Spectrum that \u2018arcade feel\u2019<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When I think back to my Spectrum days, one thing stands out above all else: the keyboard. I played an astonishing amount back then without ever using a joystick \u2013 simply because I didn\u2019t have the right interface. It was only later that I realised just how much a small accessory can change the gaming experience. And that\u2019s exactly what the Kempston Joystick Interface is: unassuming, robust \u2013 and, for many games, still the most obvious joystick option today.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Key facts<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Year of publication: 1983<\/li>\n\n\n\n<li>Manufacturer: Kempston Micro Electronics Ltd.<\/li>\n\n\n\n<li>System: Sinclair ZX Spectrum (\u00fcber den Expansionsport \/ Edge-Connector)<\/li>\n\n\n\n<li>Connection: 9-pin D-Sub (Atari standard) for joysticks<\/li>\n\n\n\n<li>Special feature: Communication via a dedicated I\/O port (Kempston standard); not a pure keyboard emulation<\/li>\n<\/ul>\n\n\n\n<!--more-->\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Two versions in my collection: \u2018standing\u2019 and \u2018lying down\u2019<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">I have two Kempston interfaces in my collection \u2013 and they differ in one respect that you notice straight away in everyday use:<\/p>\n\n\n\n<p class=\"wp-block-paragraph translation-block\"><em>Option 1: The \u2018upright\u2019 design<\/em><br>In this design, the interface is positioned quite high at the back of the Spectrum. This looks striking and sometimes requires less depth at the rear, but \u2013 depending on the joystick cable \u2013 can exert greater leverage on the connector.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/Kempston-Joystick-Interface-2-oben-1024x768.jpg\" alt=\"\" class=\"wp-image-39593\" srcset=\"https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/Kempston-Joystick-Interface-2-oben-1024x768.jpg 1024w, https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/Kempston-Joystick-Interface-2-oben-300x225.jpg 300w, https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/Kempston-Joystick-Interface-2-oben.jpg 1400w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Kempston Joystick Interface \u2013 Version 1 (top view); when connected to the Spectrum, the design appears rather \u2018upright\u2019.<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph translation-block\"><em>Option 2: The \u2018horizontal\u2019 design<\/em><br>This version sits flatter and often looks \u2018neater\u2019 on the computer because it rests on top of it. However, you may need a little more space behind the Spectrum, depending on how the computer is positioned.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"410\" height=\"308\" src=\"https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/2012\/07\/Kempston-Interface.jpg\" alt=\"Kempston Interface\" class=\"wp-image-1221\" srcset=\"https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/2012\/07\/Kempston-Interface.jpg 410w, https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/2012\/07\/Kempston-Interface-300x225.jpg 300w\" sizes=\"auto, (max-width: 410px) 100vw, 410px\" \/><figcaption class=\"wp-element-caption\">Kempston Joystick Interface \u2013 Version 2 (top view); this model sits more \u2018flat\u2019 on the Spectrum.<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph translation-block\"><strong>What both models have in common: no through-wired expansion port<\/strong><br>Interesting (and important in practice): on both of my interfaces, the expansion port is not routed out as an additional socket. This means that, with these variants, the Kempston interface is usually the last device on the expansion port. Anyone wishing to operate several expansions simultaneously (e.g. printer interface, memory or disk expansion) will then need either a different solution or a separate expansion hub.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>What makes the Kempston so special<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">There was never a single standard joystick for the Spectrum. Many joystick solutions work via keyboard mapping: the joystick internally \u2018presses\u2019 specific keys (cursor, number pad, etc.). The Kempston interface is different: it transmits the joystick status via its own hardware port. This makes the input for games and programmes very direct \u2013 and that is precisely why \u2018Kempston\u2019 became a standard over time.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In short: if a game offers \u2018Kempston\u2019 in the menu, there\u2019s a very good chance it will be responsive and enjoyable to play.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>How the query works (explained simply)<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The joystick state is returned as a number. Neutral is 0. Each direction has a fixed value, and firing adds another value to this. Diagonal movements are created by adding the values together.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><em>Typical values (Kempston standard)<\/em><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Right: 1<\/li>\n\n\n\n<li>Links: 2<\/li>\n\n\n\n<li>Down: 4<\/li>\n\n\n\n<li>Up: 8<\/li>\n\n\n\n<li>Fire: +16<\/li>\n\n\n\n<li>Centre: 0<\/li>\n\n\n\n<li>Diagonal: Sum of the directions (e.g. up + right = 8 + 1 = 9)<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><em>Mini test in BASIC<\/em><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If you want to check the interface quickly, you can do so without even needing a special programme:<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>10 PRINT IN 31\n20 GO TO 10\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">In neutral mode, the display should always show 0. If you press a directional button or the fire button, the values will change accordingly.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><em>Practical tip: mechanical stress and correct attachment<\/em><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The Spectrum\u2019s expansion port is handy, but it\u2019s not indestructible \u2013 especially after decades of use. That\u2019s why there are a few things I bear in mind whenever I\u2019m adding extensions to the Spectrum:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Always apply it straight across; don\u2019t let it tilt<\/li>\n\n\n\n<li>Do not press with force<\/li>\n\n\n\n<li>When peeling, make sure to keep the blade straight (do not tear sideways)<\/li>\n\n\n\n<li>Route the joystick cable so that it does not constantly pull on the interface<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">It is the design itself (\u2018upright\u2019 vs. \u2018horizontal\u2019) that makes all the difference here: the flatter version often looks more relaxed on a shelf or on a table, whilst the taller version is sometimes more space-saving.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"450\" src=\"https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/2012\/12\/Kempston-Joystick-Interface-und-Quickshot-Joystick.jpg\" alt=\"\" class=\"wp-image-2476\" srcset=\"https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/2012\/12\/Kempston-Joystick-Interface-und-Quickshot-Joystick.jpg 600w, https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/2012\/12\/Kempston-Joystick-Interface-und-Quickshot-Joystick-300x225.jpg 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\"><strong>Why the Kempston is an essential accessory for me these days<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">I find it almost ironic: I used to play without a joystick at all. These days, for me, a Kempston interface is one of those accessories that instantly makes the Spectrum feel \u2018complete\u2019 \u2013 not because it\u2019s technically spectacular, but because it changes the feel of the game so dramatically.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">And with two different designs in the collection, it\u2019s even better: it really brings home the point that there wasn\u2019t just \u2018the\u2019 Kempston interface, but also variants that feel quite different in everyday use \u2013 even if, ultimately, they both deliver the same standard.<\/p>","protected":false},"excerpt":{"rendered":"<p>Kempston Joystick Interface (1983) \u2013 der Standard, der dem Spectrum das \u201eArcade-Gef\u00fchl\u201c gab Wenn ich an meine Spectrum-Zeit zur\u00fcckdenke, dann war das vor allem: Tastatur. \u2026<\/p>","protected":false},"author":2,"featured_media":39593,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_lmt_disableupdate":"no","_lmt_disable":"","ngg_post_thumbnail":0,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":true,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"Neuer Artikel auf Jungsis Corner: das Kempston Joystick Interface (1983) f\u00fcr den Sinclair ZX Spectrum.\nIch habe damals tats\u00e4chlich ohne Joystick gespielt \u2013 heute liegen bei mir zwei Varianten in der Sammlung (aufrecht und liegend), beide ohne durchgeschliffenen Expansionsport. Im Artikel geht\u2019s um Geschichte, Praxis und den Kempston-Standard (Port 31) inklusive BASIC-Minittest.\n\nhttps:\/\/www.jungsi.de\/kempston-joystick-interface-sinclair-zx-spectrum\/\n\n#Sinclair #ZXSpectrum #Retrocomputing #Retrog","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false,"_links_to":"","_links_to_target":""},"categories":[102],"tags":[4737],"class_list":["post-39456","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-zx-spectrum","tag-hardware"],"modified_by":"Jungsi","wp-worthy-pixel":{"ignored":false,"public":"b4f0f151ec9749d98f24cd3d6c494d81","server":"","url":"https:\/\/vg02.met.vgwort.de\/na\/b4f0f151ec9749d98f24cd3d6c494d81"},"wp-worthy-type":"normal","jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/www.jungsi.de\/blog\/wp-content\/uploads\/Kempston-Joystick-Interface-2-oben.jpg","jetpack-related-posts":[{"id":1980,"url":"https:\/\/www.jungsi.de\/en\/sinclair-zx-spectrum-zubehor\/","url_meta":{"origin":39456,"position":0},"title":"Sinclair ZX Spectrum &#8211; Zubeh\u00f6r","author":"Jungsi","date":"1. August 2012","format":false,"excerpt":"Interface 1Das Interface 1 wurde 1983 eingef\u00fchrt und bot einen RS232 Anschluss (der neunpolige Stecker rechts im Bild), Lan-Anschl\u00fcsse (die beiden Buchsen in der Mitte) und nat\u00fcrlich den Anschluss f\u00fcr die Microdrives (der Anschluss ganz rechts). Nat\u00fcrlich wurde der Erweiterungsport herausgef\u00fchrt um weiter Interfaces anschlie\u00dfen zu k\u00f6nnen (siehe im Bild\u2026","rel":"","context":"In &quot;Retro&quot;","block_context":{"text":"Retro","link":"https:\/\/www.jungsi.de\/en\/category\/retro\/"},"img":{"alt_text":"Sinclair Spectrum 48k mit Zubeh\u00f6r","src":"https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/2012\/07\/Spectrum-komplett-300x225.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":3507,"url":"https:\/\/www.jungsi.de\/en\/retro-sinclair-zx-spectrum-interface-1bis-firmware-update\/","url_meta":{"origin":39456,"position":1},"title":"Interface 1bis: Firmware-Update","author":"Jungsi","date":"16. May 2013","format":false,"excerpt":"Schon gibt es wieder was Neues in Bezug auf das Interface 1bis: ein Firmware-Update! Da anscheinend Joysticks, die an den Joystick-Port (Kempston) angeschlossen sind, bei einigen Spielen etwas zu tr\u00e4ge reagiert haben, hat Dan Antohi schnell reagiert. Hier sein Schreiben aus dem WOS-Forum: Die Firmware wurde durch Hinzuf\u00fcgen von zwei\u2026","rel":"","context":"In &quot;Sinclair ZX Spectrum&quot;","block_context":{"text":"Sinclair ZX Spectrum","link":"https:\/\/www.jungsi.de\/en\/category\/retro\/sinclair\/zx-spectrum\/"},"img":{"alt_text":"Interface 1bis - Vorderseite","src":"https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/2013\/02\/Interface-1bis-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":14510,"url":"https:\/\/www.jungsi.de\/en\/k-mouse-2016-lp-sinclair-zx-spectrum\/","url_meta":{"origin":39456,"position":2},"title":"K-Mouse 2016 LP","author":"Jungsi","date":"15. April 2018","format":false,"excerpt":"Nach meinem Artikel \u00fcber die Neuauflage des K-Mouse Interface (2015) hier nun die Variante\u00a0K-Mouse 2016 LP. Es\u00a0bietet wieder einen USB Maus Anschluss, Joystick Interface, Reset-Knopf - dazu kommt noch ein Controller mit dem die CPU Geschwindigkeit beeinflusst werden kann. Der Composite Anschluss ist in dieser Version entfallen. Alle Einstellungen k\u00f6nnen\u2026","rel":"","context":"In &quot;Sinclair ZX Spectrum&quot;","block_context":{"text":"Sinclair ZX Spectrum","link":"https:\/\/www.jungsi.de\/en\/category\/retro\/sinclair\/zx-spectrum\/"},"img":{"alt_text":"Spectrum - K-Mouse 2016 LP","src":"https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/k-mouse-2016-lp.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/k-mouse-2016-lp.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/k-mouse-2016-lp.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/k-mouse-2016-lp.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":11739,"url":"https:\/\/www.jungsi.de\/en\/k-mouse-2015-sinclair-zx-spectrum\/","url_meta":{"origin":39456,"position":3},"title":"K-MOUSE 2015","author":"Jungsi","date":"27. July 2016","format":false,"excerpt":"Dieses Interface basiert auf dem Kempston Mouse Interface das ab 1986 von der Firma Kempston Micro Electronics Ltd. verkauft wurde. Kempston war auch der Hersteller der bekannten Joystick Interfaces. Das Mouse Interface wurde am Anfang f\u00fcr 69,95 Pfund zusammen mit einer speziellen Version des OCP Art Studio verkauft. Bei den\u2026","rel":"","context":"In &quot;Sinclair ZX Spectrum&quot;","block_context":{"text":"Sinclair ZX Spectrum","link":"https:\/\/www.jungsi.de\/en\/category\/retro\/sinclair\/zx-spectrum\/"},"img":{"alt_text":"K-Mouse 2015","src":"https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/k-mouse-2015-vorderseite.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/k-mouse-2015-vorderseite.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/k-mouse-2015-vorderseite.jpg?resize=525%2C300&ssl=1 1.5x, https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/k-mouse-2015-vorderseite.jpg?resize=700%2C400&ssl=1 2x"},"classes":[]},{"id":5790,"url":"https:\/\/www.jungsi.de\/en\/retro-sinclair-zx-spectrum-hardware-vorstellung-kempston-ram-turbo-interface\/","url_meta":{"origin":39456,"position":4},"title":"Kempston RAM Turbo Interface [Sinclair Zx Spectrum]","author":"Jungsi","date":"9. July 2014","format":false,"excerpt":"RAM Turbo Das \"RAM Turbo\" erschien 1984 (gebaut von RAM Electronics Ltd. oder auch Fleet Electronics \u2013 Preis 22,95 \u00a3) und wurde praktisch als Nachfolger und Ersatz f\u00fcr das offizielle Sinclair ZX Interface 2 entwickelt. Daher haben die beiden Ger\u00e4te auch \u00e4hnliche Geh\u00e4use.Der ZX Spectrum hatte ja urspr\u00fcngliche keine Joystick\u2026","rel":"","context":"In &quot;Retro&quot;","block_context":{"text":"Retro","link":"https:\/\/www.jungsi.de\/en\/category\/retro\/"},"img":{"alt_text":"RAM Turbo - Joystickports","src":"https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/2014\/04\/RAM-Turbo-1.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":2803,"url":"https:\/\/www.jungsi.de\/en\/retro-sinclair-spectrum-angry-space-invader\/","url_meta":{"origin":39456,"position":5},"title":"Angry Space Invader","author":"Jungsi","date":"14. May 2013","format":false,"excerpt":"Das Interface mit dem lustigen Namen ist ein einfaches Kempston\/Sinclair Joystick-Interface f\u00fcr den ZX Spectrum und Kompatible.Die Platine ist - wie von Lotharek gewohnt - sauber aufgebaut und verarbeitet. Der Anschluss an den ZX Spectrum schnell erledigt. Ab und zu w\u00e4re ein Geh\u00e4use f\u00fcr diese Ger\u00e4te nicht schlecht ;-) Information\u2026","rel":"","context":"In &quot;Sinclair ZX Spectrum&quot;","block_context":{"text":"Sinclair ZX Spectrum","link":"https:\/\/www.jungsi.de\/en\/category\/retro\/sinclair\/zx-spectrum\/"},"img":{"alt_text":"Angry Space Invader eiss\/schwarz","src":"https:\/\/i0.wp.com\/www.jungsi.de\/blog\/wp-content\/uploads\/2013\/02\/Angry-Space-Invaders-3.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]}],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/posts\/39456","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/comments?post=39456"}],"version-history":[{"count":0,"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/posts\/39456\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/media\/39593"}],"wp:attachment":[{"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/media?parent=39456"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/categories?post=39456"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.jungsi.de\/en\/wp-json\/wp\/v2\/tags?post=39456"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}