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Acknowledgements

The Javascript version of Jtyone was converted from the original EightyOne emulator which includes code by Mike Wynne and Philip Kendall. The emulator uses adapted versions of js-unzip and js-inflate to access TZX files within ZIP files.

Use on Other Web Sites

The emulator can be used subject to the following license:

/* JtyOne - A JavaScript ZX81 emulator.
 * Translated from EightyOne  - A Windows ZX80/81/clone emulator.
 * Copyright (C) 2003-2006 Michael D Wynne
 * Java translation (C) 2006 Simon Holdsworth
 * JavaScript translation (C) 2015 Simon Holdsworth
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

The original JtyOne Java emulator

You can run the ZX81 emulator outside of a web browser as an application using jtyone.jar (pesky antivirus programs may likely warn you about downloading .jar files). Run the emulator by clicking on the JAR file icon or by running it from a command line. The command line supports some additional options:

java -jar jtyone.jar 
   [tzx file name[@track number] ]
   [-scale screen size multiplier]
   [-hires {qs|dk}]
   [-machine {ZX81|ZX80}]

For example:
java -jar jtyone.jar 10Games.tzx@3 -scale 3

The file must be a .tzx file or .tzx.zip file, like the ones available on this site. The emulator doesn't load individual .P files.

The source for the JtyOne emulator is available under the GPL, as required by the EightyOne source. You can download it from here.