ZX81 1.13.5 - App Store

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About ZX81

Welcome to a taste of early 1980s home computing. This app focuses on the Sinclair ZX81 experience and is loaded with example software. Background: In 1980 the British company Science of Cambridge (later renamed Sinclair...

Welcome to a taste of early 1980s home computing. This app focuses on the Sinclair ZX81 experience and is loaded with example software. Background: In 1980 the British company Science of Cambridge (later renamed Sinclair Research) released the Sinclair ZX80 home computer. The computer was developed with another technology company, Nine Tiles, and manufactured in a Timex Corporation factory in Dundee, Scotland. Followed in March 1981 by the even more popular successor, the Sinclair ZX81, both models had a profound impact on home and hobbyist computing in the UK and many other countries. Timex Corporation and Sinclair Research continued their joint venture and released the Timex Sinclair 1000 (TS1000) and 1500 (TS1500) variants of the ZX81 for the US market in July 1982 and July 1983 respectively. Meanwhile, another iconic British home computer, the Sinclair ZX Spectrum, was under development and hit the market in April 1982... but that's another story. Special thanks to Nine Tiles for granting permission to include the ROM code, to which they retain the intellectual property rights after all these years. Additionally, many thanks to all the developers of the loaded ZX81 software who have all granted permission to include their titles in the app. We hope this list of software will continue to grow in future updates.

Version History Enables ZX81/ZX80 program file loading (iOS/iPadOS 14+). 1.13.5 04/06/2024 This update resolves crashes when: • opening the app on devices with iOS 12 • exporting a snapshot saved with the 48K RAM setting 1.13.4 04/02/2024 • Refinements to the simulated computer fonts option in the app user interface: adds a ZX80 option, now supports all ZX81 characters, reimagined characters to support other languages, and using the fonts in the memory dump viewer. • Updated Sebastien Andrivet’s Factory game. • Dr Beep’s USCII utility and LUNAPARK81 game. • 3D Star Raid game by Bukster Games. • Paul Daniels' games: QFrogger, QDepthCharge. 1.13.3 11/27/2023 Bug fix when switching between simulated computers with different logos or keyboard styling. 1.13.2 05/27/2023 • iPadOS Multi-window support added for the Z80 debugger (tap on the emulated screen to reveal the debugger option). • Export option from the saved slots to create .z81 snapshot files for the EightyOne emulator. • Updated tape player functionality to avoid a fade in transition - special thanks to Stéphane Blanchonnet for reporting the problem and testing the fix. • The latest programs from Johan Koelman: 10=, Bouncing Dots, TRICDEL, YAHTK, Cubic Maze. • Dungeons of Zedd game by Walter Ariel Risi. • Escape from Tokat Dungeon game by Salvatore Andamio. • BattleZXone game by Bukster Games. • Krystal graphics demo by Nickmann László. • Rock Crush II: The Power Of Dan (2022) game by Steven McDonald. 1.13.0 05/15/2023 • More stability fixes • RetroSnake game by Camilo Eid Jordán 1.12.2 09/18/2022 • Corrected: - multiple crash scenarios. - physical keyboard support and screenshot saving for macOS (can be installed on Apple Silicon Macs with an iPadOS interface layout). - mapping of physical quote key when the ZX80 ROM is selected. Special thanks to Allan McLeod for reporting problems and testing changes. • Super Shogun game by Dr Beep. • All of Simon Fawkes' games: Death Trap, Dodge It, Fun Fair Adventure, Pengy, Tablets of Hippocrates, Trojan Dragon. 1.12.1 07/31/2022 • Improved accuracy of inserted Z80 CPU wait states. Now scores 100% based on Dr Carlo Delhez’s Clock Frequency (CLCKFREQ) test program. Many thanks to Paul Farrow for his persistence and support in helping to reach this level of accuracy. • VSYNC 3 channel sound demo using a Tim Follin’s tune from a type-in magazine program listing. Ported by Kelly Murta. • Games by Walter Ariel Risi: Cursed Catacombs, Zeddytron 2081. • Latest game from Bukster Games: Valley of the Kings. 1.12.0 07/03/2022 • Japanese translation by Shigeru Kumokoshi • Option to jump to specific addresses in the debugger memory dump view (suggested by Jacob Krall) • Moskão Fighter game by Kelly Murta • Updated version of Against the Elements game by Paul Farrow 1.11.2 03/29/2022 • Fixed the lists styling in the Z80 debugger views for iOS/iPadOS 15 • Editing functionality for the bytes displayed in the Memory Dump debugger view • Roger Dymond’s games: Beetle, Fox and Geese, Ludo, Noughts and Crosses, Snakes and Ladders • Dr Beep’s games: Reaction, Slingshot Sam, Kayak, Sir Clive 1.11.1 01/02/2022 • New functionality to convert P files to tape audio for real ZX81 computers • Tweaks for OS & iPadOS 15 • Bitnamic Software’s 2019 deluxe version of Em Busca dos Tesouros (Treasure Quest) • John Newcombe’s ZX Reactor simulator • Dr Beep's Apple Pie game 1.11.0 09/20/2021 Fixes the Software list, which showed the incorrect computer types required for each program. 1.10.6 06/12/2021 • Added 2003 Shoulders of Giants ROM by Geoff Wearmouth including its disassembly symbols in the Z80 debugger. • Improved hardware keyboard support for iOS/iPadOS 13.4 and above: i) Arrow and other keys supported as suggested by Mikael Bonnier, ii) Maintained keypresses supported. • Fixed bug when displaying the LD (IX+d), n and LD (IY+d), n instructions in the Z80 debugger. Special thanks to Steven McDonald for reporting the problem. • Fixed bug where the app setting for the interface color style was ignored. • Zonkey Kong game by David Spinnett and Don Crawford. 1.10.5 06/12/2021 • Fixed problem with Chroma 81 address logic. Thanks to Paul Farrow and Steven McDonald identifying the problem. • Two new ZX81 ROM options: i) 622 variant identified by Lardo Boffin, Mark (AKA 1024MAK) and Moggy ii) Big Bang x2c / Shoulders of Giants started by Geoff Wearmouth and progressed by Ludwig Röck and Zsolt Gaál • Z-XTRICATOR game updated to the single file loader by Paul Farrow. • Hungarian translation by Sáfár Sándor. 1.10.4 05/02/2021 • New Z80 Debugger sub screen for viewing a memory dump • Dr Beep’s latest game: Johnnie Walker • Omega Phoenix from Bukster Games 1.10.3 03/24/2021 • Paul Farrow’s flicker free ZX80 games: ZX80 Kong & ZX80 Pacman • Dr Beep’s latest game to celebrate the 40th Anniversary of the ZX81: DIG-IT 1.10.2 03/04/2021 • Chroma 80 (Interface for ZX80) support fixed - special thanks to Paul Farrow for his guidance. • Z80 Debugger: bug fixes and new edit functionality for the values of the CPU registers • Original version of the classic game by Tadeu Curinga da Silva: Em Busca Dos Tesouros • Graphics demo by Marcin Rusinowski: 192 bytes • Latest game by Dr Beep: 2PAXMAN 1.10.1 02/17/2021 • For iOS/iPadOS 13+ there is a new Z80 debugger view accessible when tapping on the emulated screen • Danish translation of the app interface and App Store text by Thomas Kolbeck Kjær Heckmann • New version 35th Anniversary Edition of Rock Crush game by Steven McDonald • Demo by Tygrys & At0m (speccy.pl): Goodbye World 1.10.0 01/10/2021 • More bug fixes for the screenshot capture functionality when saving to the photo library • Version updates for Dr Beep’s games and some new titles: ZOXO-B-WAN, Snake Bingo, Path Maze, Hidden Picture 3, Letris, Finger Twister. • New game from Bukster Games: 3D Skeleton Maze Game 1.9.1 11/22/2020 • Improvements to the accuracy (special thanks to Paul Farrow for all his help): i) updated WAIT insert states and real world timing ii) IN/OUT VSYNC state transition points instead of end of the instructions iii) updated ULA 207 cycle reset timing during maskable interrupt response iv) updated CRT back porch duration • Spanish translation by Julio Mateos (Latin American Spanish adaptation by Ernesto Uriburu) • Improvements to screenshot saving functionality (thanks to Thomas Kolbeck Kjær Heckmann for reporting problems) • Unfinished game by The Mojon Twins: Super Refried Gun Operation • Blackjack game by Neliton Pereira 1.9.0 08/16/2020 • Corrections to the text in the settings section • New option for users that have a different preference to the main dark / light mode device setting introduced in iOS 13 (suggested by Richard Hallas) • Catalan translation for the app interface by Kevin Palser and César Hernández Bañó • New game: Jumpy in Space by Sandor Safi • Games from André Baune: Alien Mind & Yoogor 1.8.2 05/12/2020 • Fixed MIC / VSYNC sound options not being shown when the system font is selected (thanks to Steven McDonald for reporting the problem) • New option to restrict MIC / VSYNC sound to when the video frame is not stabilised • More RAM settings (requested by Richard Hallas and Rob Houghton) • Tractor Beam by Bukster Games Special thanks to Steven McDonald for his patience beta testing this version. 1.8.1 04/05/2020 • Revised sound support to reduce having to apply playback speed corrections and added support for MIC audio output • ZX81 Music Interpreter, classical tunes demo (MIC/VSYNC music) by Kelly Murta • Dr Beep’s games: Trampoline, Cylon Attack 1.8.0 03/20/2020 • Option on the software list screen to filter programs by their features (iOS 13 and above) • New version of Masada Class by Bukster Games • Latest games by Dr Beep: Max Verstappen Formula One Pitstop Simulator, Sleigh Ride, Father Time 1.7.3 01/07/2020 • Support for Layer A mode of the Recreated ZX Spectrum Bluetooth keyboard • Corrected bugs introduced in the UDG support for some of the games • Dr Beep’s latest games: Nohzdyve, Ghostbusters, Itsy Bitsy Spider, Goat and wolves, Monkeyboard, Mission Impossible: Bombsquare • David Stephenson’s game: Tut-Tut (includes UDG version by Moggy) • Latest game from Bukster Games: Calvary Class 1.7.2 11/20/2019

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Previous Versions

Here you can find the changelog of ZX81 since it was posted on our website on 2021-12-16 10:53:20. The latest version is 1.13.5 and it was updated on 2026-06-15 19:57:35. See below the changes in each version.

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