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<center><b><font size="7">Stella</font></b></center>
<br><br>
<center><h2><b>A multi-platform Atari 2600 VCS emulator</b></h2></center>
<center><h4><b>Release 6.3</b></h4></center>
<br><br>
<center><h2><b>User's Guide</b></h2></center>
<br>
<h2>Contents</h2>
<ul>
<li><a href="#History">A Brief History of the Atari 2600</a></li>
<li><a href="#Introduction">Introduction</a><br>
<ul><li><a href="#Features">Features</a></li></ul>
</li>
<li><a href="#QuickStart">Getting Started</a><br>
<ul>
<li><a href="#Requirements">Requirements</a></li>
<li><a href="#Installation">Installation</a></li>
<li><a href="#Games">Locating Game Images (aka ROMs)</a></li>
<li><a href="#Playing">Playing a Game</a></li>
<li><a href="#Keyboard">Keyboard Layout</a></li>
<li><a href="#Hotkeys">Hotkeys</a></li>
<li><a href="#ControlMap">Controller Map</a></li>
<li><a href="#TimeMachine">Stella's 'Time Machine'</a></li>
</ul>
</li>
<li><a href="#Advanced">Advanced Configuration</a><br>
<ul>
<li><a href="#CommandLine">Using the Command Line</a></li>
<li><a href="#Options">Changing Options</a></li>
<li><a href="#Remapping">Event Remapping/Input Devices</a></li>
<li><a href="#ROMInfo">ROM Launcher</a></li>
<ul>
<li><a href="#ROMInfoViewer">ROM Launcher Viewer</a></li>
<li><a href="#ROMLauncherContextMenu">ROM Launcher Context Menu</a></li>
</ul>
<li><a href="#ROMAudit">ROM Audit Mode</a></li>
<li><a href="#Adaptor">Stelladaptor/2600-daptor Support</a></li>
<li><a href="#AtariVox">AtariVox/SaveKey Support</a></li>
<li><a href="#Debugger">Developer Options/Integrated Debugger</a></li>
<li><a href="#Settings">Settings File</a></li>
<li><a href="#Cheats">Cheatcode Manager</a></li>
<li><a href="#Logs">Viewing the System Log</a></li>
<li><a href="#Properties">Game Properties</a></li>
<li><a href="#Palette">Palette Support</a></li>
</ul>
</li>
<li><a href="#Acknowledgments">Acknowledgments</a></li>
<li><a href="#License">License and Disclaimer</a></li>
</ul>
<br><br><br>
<center><b>February 1999 - June 2020</b></center>
<center><b>The Stella Team</b></center>
<center><b><a href="https://stella-emu.github.io">Stella Homepage</a></b></center>
<br>
<!-- ///////////////////////////////////////////////////////////////////////// -->
<br><br>
<p><h1>
<a name="History">A Brief History of the Atari 2600</a></h1>
<hr>
<p><a><img src="graphics/console.png" ALIGN=RIGHT></a>
In the early 1970's, video arcade games gained commercial success for the
first time. The American public was introduced to Pong, Tank, and other
interactive video games which populated amusement parks, bars, and arcades.
The games were successful enough to create interest for home versions, so in
1975 Atari released Home Pong and it was a smash hit. Other companies such as
Magnavox and Coleco followed suit and released their own dedicated console
games. Then in 1976, Fairchild Camera and Instrument introduced the Channel F
system, the first cartridge based home video game system. The industry
recognized that cartridge systems were the future of video gaming, and began
development in that direction. In January 1977, RCA released the Studio II,
another cartridge based system, although it only projected in black and white
and seemed to be focused on educational titles. Then, in October 1977, Atari
released the Atari VCS (Video Computer System) with an initial offering of nine
games. This system, later renamed the Atari 2600, took the industry by storm
and dominated the marketplace for years to come.
</p>
<p><a><img src="graphics/chucky_cheese.png" ALIGN=LEFT></a>
Because of oversupply, the Christmas season of 1977 was very rough on the
video game industry, and the Atari 2600 was the only system that managed to
emerge unscathed. Atari enjoyed strong sales in 1978 and a fantastic holiday
season, as Atari released more games such as Outlaw, Spacewar, and Breakout.
Internally however, Atari was at odds. Nolan Bushnell, the inventor of pong and
founder of Atari, wound up leaving the company and purchased Pizza Time Theater,
which later became the successful Chuck E. Cheese! In 1979 Atari continued
their trend and released 12 more games which met with continued success.
However, Atari was now facing some stiffer competition from the Mattel
Intellivision and the Magnavox Odyssey2.
</p>
<p><a><img src="graphics/space_invaders.png" ALIGN=RIGHT></a>
Atari needed a mega-hit in 1980 in order to squash the competition, and they
found it in the home version of a game from Japan called Space Invaders. It was
so popular that people were buying the Atari 2600 just so they could play Space
Invaders at home. Following that, Atari released Adventure, which was the first
video game to contain an Easter Egg - placing an object in a certain area
revealed the programmer's name, Warren Robinett. 1980 was important for another
reason - the creation of the first ever third party software producer, Activision.
The company was formed by four Atari employees who were unsatisfied with the
working conditions at the company. They released four games initially: Dragster,
Fishing Derby, Checkers and Boxing. The games were very well received by the
public, and revealed that the Atari 2600 was capable of better games than
Atari themselves had been producing. Atari tried to prevent Activision from
selling games, but they failed and Activision grossed $70 million that year.
</p>
<p>
By 1981, the video game industry was basically a horse race between the 2600
and the Intellivision. While the Intellivision was technologically superior in
some respects, the 2600 continued to lead in sales. Atari released the home
version of Asteroids, which was a huge success. Inspired by the success of
Activision, another software development group called Imagic was formed. They
would not release any games until 1982 however. Another company, Games by Apollo,
was formed in Texas and released several games that year.
</p>
<p>
Coleco entered the market in 1982 with the release of the graphically
superior Colecovision. To combat this new system, Atari produced the 5200,
a technologically comparable system. The 2600 dropped $100 in price in order
to remain competitive. Then a company called Arcadia released a peripheral
called the Supercharger which played games in an audio cassette medium. This
allowed for multiple loads and expanded the 2600's capabilities.
<p><a><img src="graphics/pacman.png" ALIGN=LEFT></a>
Atari released Pac-Man and E.T. that year, two incredibly hyped games which
were critical flops.
Although Pac-Man sold many copies, it was considered to be a poor
translation of the arcade hit. However, there were many fantastic games
produced for the 2600 during this period, and it was still selling strong.
</p>
<p>
Ever since the inception of Activision, Atari had been fighting to keep third
parties from producing cartridges which they felt were stealing profits from
them. Finally the issue was settled when Atari agreed to allow third party
manufacturing in exchange for a royalty. Suddenly software companies began
popping up all over, and 1982 saw releases from companies like Venturevision,
Spectravision, Telesys, CBS, 20th Century Fox, US Games, M Network, Tigervision,
Data Age, Imagic and Coleco. There was even a company that released a line of
X-Rated games for the 2600 called Mystique. The year was financially successful
for Atari, however there seemed to be a glut of software. Although there were
many quality titles still produced, there was an increasing number of rushed
games as manufacturers attempted to cash in on the craze.
</p>
<p>
More companies jumped on the band wagon in 1983. Zimag, Ultravision, Amiga,
and others were also producing games and peripherals. It seemed as if there was
just too much product to meet the demand, and as it turned out there was. By
the end of the year, companies began folding. US Games, Data Age, Games by
Apollo, Telesys and others all closed their doors from poor sales. A video
game crash was occurring, and all companies were taking it on the chin.
</p>
<p>
1984 was a much more subdued year for the Atari 2600, and the price of the
system had now dropped to $40-$50. Many were saying that the video game
industry was dead. However, Atari surprised everyone by announcing the release
of the 7800, and also promising more 2600 games with improved graphics and
sound. Unfortunately, neither of these things happened in 1984 because Atari
sold their home video game division to Jack Tramiel who believed that home
computers would replace video game systems. No further mention of the 2600 or
7800 was made that year, and it appeared that they might be dead.
</p>
<p>
1985 was another very quiet year for Atari and video games in general, and only
a few games were released for the 2600. Activision produced Cosmic Commuter and
Ghostbusters, but with little fanfare or marketing, these games did not sell
well. However, because of the huge game library and cheap price, Atari still
sold over a million 2600 consoles in 1985.
</p>
<p>
There were very few plans for home video game systems by any company in 1986,
since the market appeared to be dead. Then, to most people's surprise, Nintendo
brought the NES to America and it was a smash hit, proving that video games
still had a place in the US. Atari decided that maybe it would be a good idea
to release the 7800 units it had in storage, and produce some more 2600 games.
The 7800 was released with only 3 games initially available, although it was
compatible with the 2600 library. They also redesigned the 2600 as the 2600 Jr.,
a machine with the same abilities, but a new look and marketing campaign. It
was sold for less than $50.
</p>
<p><a><img src="graphics/jr_pacman.png" ALIGN=RIGHT></a>
Video games were once again selling phenomenally in 1987. Atari released
several new titles, including Jr. Pac-Man, and also licensed a number of games
from other companies such as Donkey Kong and Q*Bert. These new titles sold for
$10-$15. Interestingly, a number of titles began appearing again from third
part companies such as Epyx, Froggo, and Exus. It seemed that the 2600 was not
dead yet!
<p><a><img src="graphics/secret_quest.png" ALIGN=LEFT></a>
In 1988, Atari rehired Nolan Bushnell and announced a number of new
titles, including Secret Quest, a game written by Mr. Bushnell himself. Atari
continued to manufacture these games even until 1989. However, it was apparent
that the 2600, after its introduction over a decade ago, was finally at the end
of its run. Although it was still produced and marketed outside of the US, the
Atari 2600 finished its run in America. No other console has had such a long
history or sold as many systems in the U.S.
</p>
<p>
Today, the 2600 still has a large number of fans who remember the countless
games played over the years, and the years to come. There are even games being
produced by hobbyists, some of them quite professionally, being released on
newly burnt cartridges with labels and manuals. And the recent trend in
retrogaming has brought many more video game fans to rediscover the 2600, and
it continues to live on 22 years after its release!
</p>
<p><i>Alexander Bilstein<br>February 1999</i></p>
<!-- ///////////////////////////////////////////////////////////////////////// -->
<br><br>
<p><h1>
<a name="Introduction">Introduction</a></h1>
<hr>
<p>
Stella is a freely distributed multi-platform Atari 2600 VCS emulator; originally
developed for Linux by Bradford W. Mott, it is now maintained by Stephen Anthony.
Stella allows you to enjoy all of
your favorite 2600 games once again by emulating the 2600's hardware with
software. Stella is written in C++, which allows it to be ported to other
operating systems and architectures. Since its original release Stella has
been ported to AcornOS, AmigaOS, DOS, FreeBSD, Linux, MacOS, OpenStep, OS/2,
Unix, and Windows, as well as consoles such as Sega Dreamcast, GP2X, Nintendo
DS and Playstation Portable (among others).
</p>
<p>
</h1>
<h2><b><a name="Features">Features</a></b></h2>
<ul>
<li>High speed emulation using optimized C++14 code</li>
<li>Supports high quality TIA emulation using the cycle-exact TIA core from
<a href="https://github.com/6502ts/6502.ts">6502.ts</a> by
Christian Speckner</li>
<li>Supports high quality sound emulation using code derived from Chris Brenner's
Atari 2600 FPGA project, including cycle-exact audio, analog interference
from mixing of audio channels, as well as stereo sound support; dynamic
sound resampling is also included</li>
<li>Emulates the Atari 2600 Joystick, Paddle, Driving, CBS BoosterGrip, Sega Genesis, QuadTari controllers using your computer's keyboard,
joysticks or mouse</li>
<li>Emulates CX22/CX80 style Trackballs, Amiga/Atari Mouse, Mindlink controller and the Light Gun using your
computer's mouse</li>
<li>Emulates the Atari 2600 Keyboard controllers using your computer's keyboard</li>
<li>Emulates <a href="http://en.wikipedia.org/wiki/CompuMate">Spectravideo CompuMate</a> system using your computer's keyboard,
including mapping of CompuMate 'Backspace', 'Space' and 'Enter' functionality to
to the actual keys on your keyboard</li>
<li>Supports autodetection for most common controller types</li>
<li>Support for real Atari 2600 controllers using the
<a href="http://www.grandideastudio.com/portfolio/stelladaptor-2600">Stelladaptor</a> and
<a href="http://2600-daptor.com">2600-daptor/2600-daptor II</a></li>
<li>Support for the speech portion of a real
<a href="http://atariage.com/store/index.php?l=product_list&c=98">
AtariVox</a> device connected to your PC using a USB adaptor</li>
<li>Supports EEPROM emulation for <a href="http://atariage.com/store/index.php?l=product_list&c=98">
AtariVox</a> and <a href="http://www.vectrex.biz/MemCard.htm">SaveKey</a> controllers,
as well as FLASH support in various cartridge schemes</li>
<li>Supports all known bankswitching schemes (let us know if there's one we missed)</li>
<li>Supports DPC+/CDF(J)(+) bankswitching schemes from the <a href="http://harmony.atariage.com">Harmony Cart</a>,
including <a href="http://thumbulator.blogspot.ca">partial emulation of the ARM processor</a></li>
<li>Supports cartridge autodetection for almost all bankswitching schemes</li>
<li>Supports using ROM filename extensions to force specific bankswitching schemes</li>
<li>Supports using ROM filename to force specific display formats</li>
<li>Supports Supercharger single-load and multi-load games</li>
<li>Supports the usual raw A26/BIN/ROM formats, also when stored in ZIP files</li>
<li>Supports property file for setting the properties associated with games</li>
<li>Supports the NTSC, PAL and SECAM television standards in 50Hz and 60Hz mode</li>
<li>Supports autodetection of display format for 50Hz vs. 60Hz modes</li>
<li>Supports most "undocumented features" of the TIA graphics chip used by
some games</li>
<li>TIA emulation supports full collision checking, with ability to disable
TIA sprites and collisions for each object separately</li>
<li>Full system state save/load functionality</li>
<li>Automatic save state creation ('Time Machine') which allows moving back and forth in the recorded timeline</li>
<li>Cross-platform UI including a built-in ROM launcher frontend</li>
<li>Built-in extensive debugger, including static analysis with the Distella disassembler
and dynamic analysis at runtime by tracking code/graphics/data sections, and
generation of DASM-compatible disassembly files</li>
<li>Emulation of CRT TV systems using <a href="http://slack.net/~ant/libs/ntsc.html">
Blargg filtering</a>, including presets for several common TV outputs
(Composite, S-Video, RGB, etc.), and ability to fully customize
many attributes (contrast, brightness, saturation, gamma, etc.).</li>
<li>Built-in ROM database with information partially compiled by
<a href="http://www.atarimania.com/rom_collection_archive_atari_2600_roms.html">
RomHunter</a></li>
</ul>
<!-- ///////////////////////////////////////////////////////////////////////// -->
<br><br>
<p><h1>
<a name="QuickStart">Getting Started</a></h1>
<hr>
<h2><b><a name="Requirements">Requirements</a></b></h2>
<blockquote>
<p>The following sections outline the basic system requirements for running
Stella under various operating systems.</p>
<p>
<h3><b><u>General</u> (required for all versions of Stella)</b></h3>
<ul>
<li>SDL version 2.0.3 or greater, latest version highly recommended</li>
<li>15/16 bit color minimum; 24/32 bit color graphics card highly recommended</li>
<li>Enough RAM for the OS + 256MB RAM for the emulation; 512MB+ highly recommended</li>
<li>Joysticks or gamepads are highly recommended</li>
<li>Mouse or <a href="http://www.grandideastudio.com/portfolio/stelladaptor-2600">Stelladaptor</a>/<a href="http://2600-daptor.com">2600-daptor</a>
with real paddles required for paddle emulation</li>
<li>Some ROM images (see <a href="http://www.atariage.com">AtariAge</a> for more information)</li>
</ul>
<p>
<h3><b><u>Linux/UNIX</u></b></h3>
<p>The Linux version of Stella is designed to work on a Linux Workstation with
the following:</p>
<ul>
<li>i386 or x86_64 class machine, with 32 or 64-bit distribution</li>
<li>OpenGL capable video card</li>
<li>Other architectures (MIPS, PPC, PPC64, etc.) have been confirmed to work,
but aren't as well tested as i386/x86_64</li>
<li>GNU g++ v/6 or Clang v/3.9 (with C++14 support) and the make utility are required for compiling the Stella source code</li>
</ul>
<p>
<h3><b><u>Macintosh</u></b></h3>
<p>The Mac version of Stella is designed to work on an Apple Macintosh with
the following:</p>
<ul>
<li>macOS 10.7 or above</li>
<li>64-bit Intel processor</li>
<li>OpenGL capable video card</li>
<li>Xcode 8.0 is required to compile the Stella source code</li>
</ul>
<p>
<h3><b><u>Windows</u></b></h3>
<p>The Windows version of Stella is designed to work on Windows Vista/7/8/10
with the following:</p>
<ul>
<li>Direct3D or OpenGL capable video card</li>
<li>Visual C++ 2017/2019 Community is required to compile the Stella source code</li>
</ul>
<p>
<h3><b><u>Other</u></b></h3>
<p>Stella is extremely portable, and in its lifetime has been ported to almost every
platform where the SDL library exists. It is 32/64-bit and endian clean in Linux/Unix, macOS
and Windows. The Stella Team is interested in hearing about any problems you may
encounter with diverse operating systems and CPU types.</p>
</blockquote></br>
<h2><b><a name="Installation">Installation</a></b></h2>
<blockquote>
<p>Stella is distributed in both source and binary form. In general, you should always
download and install the appropriate binary version. Compiling from source is only
recommended for developers, or if the binary version doesn't work for some reason.
Once you have a Stella distribution you should follow the instructions for your
operating system given below.</p>
<p>
<h3><b><u>Linux/UNIX</u></b></h3>
<ul>
<li><b>Binary DEB</b> (stella-<i>release</i>-1_arch.deb)
<ul>
<li>Install the binary DEB with the following command:
<pre> dpkg -i stella-<i>release</i>-1_arch.deb</pre></li>
</ul>
</li>
<li><b>Binary RPM</b> (stella-<i>release</i>-1.arch.rpm)
<ul>
<li>Install the binary RPM with the following command:
<pre> rpm -Uvh stella-<i>release</i>-1.arch.rpm</pre></li>
</ul>
</li>
<li><b>Building and installing from source code</b>
<ul>
<li>See the developers build instructions at the
<a href="https://stella-emu.github.io/development.html">Stella Development Page</a>.
</ul>
</li>
</ul>
<p>
<h3><b><u>Macintosh</u></b></h3>
<ul>
<li><b>Binary DMG file</b> (Stella-<i>release</i>-macos.dmg)
<ul>
<li>Double-click the disk image, open the 'Stella' folder, then copy the
<b>Stella.app</b> package to your 'Applications' folder.</li>
</ul>
</li>
<br/>
<li><b>Building and installing from source code</b>
<ul>
<li>See the developers build instructions at the
<a href="https://stella-emu.github.io/development.html">Stella Development Page</a>.
</ul>
</li>
</ul>
<p>
<h3><b><u>Windows</u></b></h3>
<ul>
<li><b>Binary EXE installer</b> (stella-<i>release</i>-<i>arch</i>.exe)
<ol>
<li>Double-click on the installer and follow the onscreen instructions</li>
</ol>
</li>
<br/>
<li><b>Binary ZIP file</b> (stella-<i>release</i>-windows.zip)
<ol>
<li>Unzip the binary ZIP file using <b>Winzip</b> or <b>Total Commander</b></li>
<li>Copy the contents of either 32-bit or 64-bit directory somewhere on your system</li>
</ol>
</li>
<br/>
<li><b>Building and installing from source code</b>
<ul>
<li>See the developers build instructions at the
<a href="https://stella-emu.github.io/development.html">Stella Development Page</a>.
</ul>
</li>
</ul>
</blockquote></br>
<h2><b><a name="Games">Locating Game Images (aka ROMs)</a></b></h2>
<blockquote>
<p>
<h3><b><u>Cartridges</u></b></h3>
<p>Most games for the Atari 2600 came on cartridges. A cartridge usually
consists of a single Read Only Memory (ROM) chip which contains the data and
code for the game. Plugging a cartridge into the Atari 2600 allows the 2600's
microprocessor to access the program stored on the cartridge.</p>
<p>In a similar way you must "plug" a copy of a cartridge into Stella when you
want to play it. Having a ROM image/BIN file of the cartridge allows you to
do this. A ROM image is a file, which contains the actual data and code read
from the cartridge. There are several ways to obtain a ROM image of a
cartridge:</p>
<p><ul>
<li>Search around the internet and find ROM images to download (websites such
as <a href="http://atariage.com">AtariAge</a> and
<a href="http://www.atarimania.com/rom_collection_archive_atari_2600_roms.html">
AtariMania/RomHunter</a> may be useful). Many homebrewers make their ROMs available too.</li>
<li>You can purchase the Atari 2600 Action Packs by Activision and use
their ROM images</li>
<li>If you're handy with a soldering iron then you can design and build a
device that plugs into a PC and read the data from the cartridge</li>
</ul>
<p><b>WARNING:</b> It may be illegal to use ROM images of games that you do not
actually own since these games may still be copyrighted.</p>
<p>
<h3><b><u>Supercharger Cassettes</u></b></h3>
<p>Supercharger games were not stored on cartridges instead they were stored
on cassette tapes. The Supercharger, which plugged into the Atari 2600's
cartridge slot, loaded games into its 6K of Random Access Memory (RAM) using a
standard audio cassette player. The Supercharger also supported multi-loading,
which allowed games to be broken into several segments and loaded at different
times. This was useful for large games which had distinct parts such as role
playing games.</p>
<p>Most of the available Supercharger ROM images are stored in 8448 bytes files.
However, ROM images of multi-load games are sometimes stored in a set of 8448
byte files. The names of these files have a two character sequence number in
them which indicates what load they are. The sequence starts with zero, skips
a few numbers and then increments by one.</p>
<p>Stella supports multi-load games, however, the set of ROM images must be
combined into a single ROM image file. For example to create a multi-load ROM
image file for Survival Island you would do the following under Unix:
<pre> % cat survivl0.bin survivl6.bin survivl7.bin > survivl.bin</pre>
or to create it under DOS you would:
<pre> % copy /b survivl0.bin+survivl6.bin+survivl7.bin survivl.bin</pre>
<p>Once you have the multi-load ROM image file, survivl.bin in this case, you
can play the game using it.</p>
<p>
<h3><b><u>Supported File formats</u></b></h3>
<p>Stella supports ROMs ending with extensions .a26, .bin, .rom, and .zip.
For the ZIP archive format, Stella will look into the archive and if it
contains only one ROM image file, Stella will automatically load it. If an
archive contains many such files, Stella will display a <i>virtual
filesystem</i> with the contents of the archive. This can be then browsed
like a normal directory.</p>
<p>Other extensions are also possible, namely to force a specific bankswitch scheme.
Normally, the bankswitching scheme for a ROM is determined automatically,
or manually by setting a <a href="#Properties">ROM property</a>, and you never
have to do anything yourself. However, it is also possible to force the
bankswitch type to use by adding a special filename extension. These extensions
are listed in the <a href="#Properties">ROM properties</a> section under
<a href="#PropertiesCartType">Cart.Type -&gt; File Extension</a>.</p>
<p><b>Note:</b> These extensions are the same as those used by the Harmony Cart
and Unocart and are not case-sensitive, so you can name your files and have them
work across all applications. <u>Again, to be clear, this is only necessary when
you want to override the default bankswitching scheme for a ROM.</u> <b>This will
not normally be necessary.</b></p>
</blockquote></br>
<h2><b><a name="Playing">Playing a Game</a></b></h2>
<blockquote>
<p>Once Stella is installed and you have some ROM images you're almost ready to
start playing.</p>
<p>
<h3><b><u>Integrated GUI</u></b></h3>
<p>Stella contains an integrated GUI for all ports. Commandline support is also
available for those who want to use it.</p>
<p>If you start Stella and do not specify a ROM image, it will start in
'ROM Launcher' mode:<br><br>
<img src="graphics/launcher.png"></p>
<p>If this is your first time starting Stella, you may have to navigate to your ROMs.
The path of the first ROM you play automatically defines the default ROM path. You
can change it later in the <b><a href="#ROMInfo">ROM Launcher</a></b> dialog.</p>
<p>At this point, you may want to set the locations for snapshots. This is described in more detail in <b>Advanced Configuration - <a href="#Snapshots">Snapshot Settings</a></b>.
These settings are optional, and can be left at the defaults if you won't be using
snapshots in the ROM launcher.</p>
<p>You can start emulation by selecting a ROM and pressing 'Enter' or clicking 'Select',
or double-clicking a ROM. Note that some games require you to 'Reset' the console
before you start playing. In this case, you need to hit the virtual reset switch,
which by default is the F2 key. Also, some games may require that you press the
joystick fire button to begin, which by default is the Left Control or Space key(s),
or button 0 on your joystick. If a game uses a more complex controller, see
<b>Getting Started - <a href="#Keyboard">Keyboard Layout</a></b>
for more information. To exit a game and re-enter the ROM launcher, press the 'Escape'
key.</p>
<p>Using the 'Search' textbox in the upper-right of the ROM launcher, the
listing can be narrowed down, showing only the ROMs that match the pattern
you enter.</p>
<p>While the file listing is in focus, you can type some characters, and the listing
will 'jump' to the file that matches what you typed. This is case-insensitive. Hold
down the Shift key on the first character to select directories instead. The delay
between successive keypresses being treated as part of one word is controlled by the
'listdelay' option; see <b>User Interface Settings</b> to change this setting.</p>
<p>
<h3><b><u>Command Menu</u></b></h3>
<p>While playing a game, normally one would use the keyboard shortcuts for controlling the
'virtual' switches in Stella (ie, the commands associated with the
function keys as described in
<b>Getting Started - <a href="#Keyboard">Keyboard Layout</a></b>).
However, another alternative is available. Pressing the '\' key toggles
a command menu dialog as follows:</p>
<p><img src="graphics/commandmenu.png"></p>
<p>This dialog contains a set of buttons that represent the same functionality
as the function keys and display the current state. You may find this useful if
you cannot remember all the function key events, or you wish to use Stella
without a keyboard (ie, in a standalone gaming system).</p>
</blockquote></br>
<h2><b><a name="Keyboard">Keyboard Layout</a></b></h2>
<blockquote>
<p>The Atari 2600 console controls and controllers are mapped to the computer's
keyboard as shown in the following tables. However, most of these events can be
remapped to other keys on your keyboard or buttons on your joystick (see
<b>Advanced Configuration - <a href="#Remapping">Event Remapping</a></b>).
The tables below show the default settings.<br/><br/>
Note: All key names are based on the US QWERTY <a href="https://en.wikipedia.org/wiki/Keyboard_layout">
keyboard layout.</a>. If you use a different layout some keys may differ. You can use the
following layout image as reference where to find the US keys on your keyboard.
</p>
<p><img src="graphics/qwertz.png"></p>
</blockquote></br>
<h2><b><a name="Hotkeys">Hotkeys</a></b></h2>
<blockquote>
<p><b>Console Controls (can be remapped)</b></p>
<table BORDER=2 cellpadding=4>
<tr>
<th>Function</th>
<th>Key (Standard)</th>
<th>Key (macOS)</th>
</tr>
<tr>
<td>Exit emulator</td>
<td>Control + q</td>
<td>Cmd + q</td>
</tr>
<tr>
<td>Exit game mode/enter launcher mode</td>
<td>Escape</td>
<td>Escape</td>
</tr>
<tr>
<td>Enter/exit options mode</td>
<td>Tab/Escape</td>
<td>Tab/Escape</td>
</tr>
<tr>
<td>Enter/exit command mode</td>
<td>Backslash (\)</td>
<td>Backslash (\)</td>
</tr>
<tr>
<td>Enter/exit debugger</td>
<td>Backquote (`)</td>
<td>Backquote (`)</td>
</tr>
<tr>
<td>Select Game</td>
<td>F1</td>
<td>F1</td>
</tr>
<tr>
<td>Reset Game</td>
<td>F2</td>
<td>F2</td>
</tr>
<tr>
<td>Color TV</td>
<td>F3</td>
<td>F3</td>
</tr>
<tr>
<td>Black/White TV</td>
<td>F4</td>
<td>F4</td>
</tr>
<tr>
<td>Left Player Difficulty A</td>
<td>F5</td>
<td>F5</td>
</tr>
<tr>
<td>Left Player Difficulty B</td>
<td>F6</td>
<td>F6</td>
</tr>
<tr>
<td>Right Player Difficulty A</td>
<td>F7</td>
<td>F7</td>
</tr>
<tr>
<td>Right Player Difficulty B</td>
<td>F8</td>
<td>F8</td>
</tr>
<tr>
<td>Save state to current slot</td>
<td>F9</td>
<td>F9</td>
</tr>
<tr>
<td>Save all Time Machine states</td>
<td>Alt + F9</td>
<td>Cmd + F9</td>
</tr>
<tr>
<td>Change to previous state slot</td>
<td>Shift + F10</td>
<td>Shift + F10</td>
</tr>
<tr>
<td>Change to next state slot</td>
<td>F10</td>
<td>F10</td>
</tr>
<tr>
<td>Automatically change state slot</td>
<td>Alt + F10</td>
<td>Cmd + F10</td>
</tr>
<tr>
<td>Load state from current slot</td>
<td>F11</td>
<td>F11</td>
</tr>
<tr>
<td>Load all states into Time Machine</td>
<td>Alt + F11</td>
<td>Cmd + F11</td>
</tr>
<tr>
<td>Save PNG snapshot</td>
<td>F12</td>
<td>F12</td>
</tr>
<tr>
<td>Pause/resume emulation</td>
<td>Pause</td>
<td>Shift-Cmd + p</td>
</tr>
</table>
<p><b>Joystick/BoosterGrip Controller (can be remapped)</b></p>
<table BORDER=2>
<tr>
<th>Left Joystick (Joy0)</th>
<th>Right Joystick (Joy1)</th>
</tr>
<tr>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Joystick Up</td>
<td>Up arrow</td>
</tr>
<tr>
<td>Joystick Down</td>
<td>Down arrow</td>
</tr>
<tr>
<td>Joystick Left</td>
<td>Left arrow</td>
</tr>
<tr>
<td>Joystick Right</td>
<td>Right arrow</td>
</tr>
<tr>
<td>Fire Button</td>
<td>Left Control, Space</td>
</tr>
<tr>
<td>Top Booster Button</td>
<td>4</td>
</tr>
<tr>
<td>Handle Grip Trigger</td>
<td>5</td>
</tr>
</table>
</td>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Joystick Up</td>
<td>Y</td>
</tr>
<tr>
<td>Joystick Down</td>
<td>H</td>
</tr>
<tr>
<td>Joystick Left</td>
<td>G</td>
</tr>
<tr>
<td>Joystick Right</td>
<td>J</td>
</tr>
<tr>
<td>Fire Button</td>
<td>F</td>
</tr>
<tr>
<td>Top Booster Button</td>
<td>6</td>
</tr>
<tr>
<td>Handle Grip Trigger</td>
<td>7</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>Sega Genesis Controller (cannot be remapped, always associated with joystick and booster-grip controllers)</b></p>
<table BORDER=2>
<tr>
<th>Left Pad</th>
<th>Right Pad</th>
</tr>
<tr>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Pad Up</td>
<td>Same as 'Joy0 Up'</td>
</tr>
<tr>
<td>Pad Down</td>
<td>Same as 'Joy0 Down'</td>
</tr>
<tr>
<td>Pad Left</td>
<td>Same as 'Joy0 Left'</td>
</tr>
<tr>
<td>Pad Right</td>
<td>Same as 'Joy0 Right'</td>
</tr>
<tr>
<td>Button 'B'</td>
<td>Same as 'Joy0 Fire'</td>
</tr>
<tr>
<td>Button 'C'</td>
<td>Same as 'Joy0 Top Booster Button'</td>
</tr>
</table>
</td>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Pad Up</td>
<td>Same as 'Joy1 Up'</td>
</tr>
<tr>
<td>Pad Down</td>
<td>Same as 'Joy1 Down'</td>
</tr>
<tr>
<td>Pad Left</td>
<td>Same as 'Joy1 Left'</td>
</tr>
<tr>
<td>Pad Right</td>
<td>Same as 'Joy1 Right'</td>
</tr>
<tr>
<td>Button 'B'</td>
<td>Same as 'Joy1 Fire'</td>
</tr>
<tr>
<td>Button 'C'</td>
<td>Same as 'Joy1 Top Booster Button'</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>Driving Controller (cannot be remapped, always associated with joystick controller)</b></p>
<table BORDER=2>
<tr>
<th>Left Driving</th>
<th>Right Driving</th>
</tr>
<tr>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Left Direction</td>
<td>Same as 'Joy0 Left'</td>
</tr>
<tr>
<td>Right Direction</td>
<td>Same as 'Joy0 Right'</td>
</tr>
<tr>
<td>Fire Button</td>
<td>Same as 'Joy0 Fire'</td>
</tr>
</table>
</td>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Left Direction</td>
<td>Same as 'Joy1 Left'</td>
</tr>
<tr>
<td>Right Direction</td>
<td>Same as 'Joy1 Right'</td>
</tr>
<tr>
<td>Fire Button</td>
<td>Same as 'Joy1 Fire'</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>Trackball Controller (uses mouse, left port only)</b></p>
<table BORDER=2>
<tr>
<th>Left Trackball</th>
</tr>
<tr>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Fire Button</td>
<td>Same as 'Joy0 Fire'</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>Light Gun Controller (uses mouse, left port only)</b></p>
<table BORDER=2>
<tr>
<th>Left Light Gun</th>
</tr>
<tr>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Fire Button</td>
<td>Same as 'Joy0 Fire'</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>Paddle Controller digital emulation (can be remapped)</b></p>
<table BORDER=2>
<tr>
<th>Left Paddles</th>
<th>Right Paddles</th>
</tr>
<tr>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Paddle 0 Turn Left</td>
<td>Left arrow</td>
</tr>
<tr>
<td>Paddle 0 Turn Right</td>
<td>Right arrow</td>
</tr>
<tr>
<td>Paddle 0 Fire</td>
<td>Left Control, Space</td>
</tr>
<tr>
<td>Paddle 1 Turn Left</td>
<td>Up arrow</td>
</tr>
<tr>
<td>Paddle 1 Turn Right</td>
<td>Down arrow</td>
</tr>
<tr>
<td>Paddle 1 Fire</td>
<td>4</td>
</tr>
</table>
</td>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Function</th>
<th>Key</th>
</tr>
<tr>
<td>Paddle 2 Turn Left</td>
<td>G</td>
</tr>
<tr>
<td>Paddle 2 Turn Right</td>
<td>J</td>
</tr>
<tr>
<td>Paddle 2 Fire</td>
<td>F</td>
</tr>
<tr>
<td>Paddle 3 Turn Left</td>
<td>Y</td>
</tr>
<tr>
<td>Paddle 3 Turn Right</td>
<td>H</td>
</tr>
<tr>
<td>Paddle 3 Fire</td>
<td>6</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>Keypad Controller (can be remapped)</b></p>
<table BORDER=2>
<tr>
<th>Left Keypad</th>
<th>Right Keypad</th>
</tr>
<tr>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Pad Button</th>
<th>Key</th>
</tr>
<tr>
<td>1</td>
<td>1</td>
</tr>
<tr>
<td>2</td>
<td>2</td>
</tr>
<tr>
<td>3</td>
<td>3</td>
</tr>
<tr>
<td>4</td>
<td>Q</td>
</tr>
<tr>
<td>5</td>
<td>W</td>
</tr>
<tr>
<td>6</td>
<td>E</td>
</tr>
<tr>
<td>7</td>
<td>A</td>
</tr>
<tr>
<td>8</td>
<td>S</td>
</tr>
<tr>
<td>9</td>
<td>D</td>
</tr>
<tr>
<td>.</td>
<td>Z</td>
</tr>
<tr>
<td>0</td>
<td>X</td>
</tr>
<tr>
<td>#</td>
<td>C</td>
</tr>
</table>
</td>
<td>
<table BORDER=1 cellpadding=4>
<tr>
<th>Pad Button</th>
<th>Key</th>
</tr>
<tr>
<td>1</td>
<td>8</td>
</tr>
<tr>
<td>2</td>
<td>9</td>
</tr>
<tr>
<td>3</td>
<td>0</td>
</tr>
<tr>
<td>4</td>
<td>I</td>
</tr>
<tr>
<td>5</td>
<td>O</td>
</tr>
<tr>
<td>6</td>
<td>P</td>
</tr>
<tr>
<td>7</td>
<td>K</td>
</tr>
<tr>
<td>8</td>
<td>L</td>
</tr>
<tr>
<td>9</td>
<td>;</td>
</tr>
<tr>
<td>.</td>
<td>,</td>
</tr>
<tr>
<td>0</td>
<td>.</td>
</tr>
<tr>
<td>#</td>
<td>/</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>CompuMate Controller (cannot be remapped)</b></p>
<table BORDER=2 cellpadding=4>
<tr><th>CompuMate</th> <th>Key</th></tr>
<tr><td>0 - 9 </td><td>0 - 9 </td></tr>
<tr><td>A - Z </td><td>A - Z </td></tr>
<tr><td>Comma </td><td>Comma </td></tr>
<tr><td>Period </td><td>Period </td></tr>
<tr><td>Func </td><td>Control (left or right) </td></tr>
<tr><td>Shift </td><td>Shift (left or right) </td></tr>
<tr><td>Enter </td><td>Return/Enter </td></tr>
<tr><td>Space </td><td>Space </td></tr>
<tr><td>Func-Space </td><td>Shift + Backspace </td></tr>
<tr><td>+ </td><td>+ or Shift + 1 </td></tr>
<tr><td>- </td><td>- or Shift + 2</td></tr>
<tr><td>* </td><td>Shift + 3 </td></tr>
<tr><td>/ </td><td>/ or Shift + 4 </td></tr>
<tr><td>= </td><td>= or Shift + 5 </td></tr>
<tr><td>? </td><td>? (Shift + /) or Shift + 6 </td></tr>
<tr><td>$ </td><td>Shift + 7 </td></tr>
<tr><td>[ </td><td>[ or Shift + 8 </td></tr>
<tr><td>] </td><td>] or Shift + 9 </td></tr>
<tr><td>&quot; </td><td>" (Shift + ') or Shift + 0 </td></tr>
</table>
<p><b>Audio & Video Keys (can be remapped)</b></p>
<table BORDER=2 cellpadding=4>
<tr>
<th>Function</th>
<th>Key (Standard)</th>
<th>Key (macOS)</th>
</tr>
<tr>
<td>Toggle sound</td>
<td>Control + ]</td>
<td>Control + ]</td>
</tr>
<tr>
<td><i>Decrease</i> volume</td>
<td>Alt + [</td>
<td>Cmd + [</td>
</tr>
<tr>
<td><i>Increase</i> volume</td>
<td>Alt + ]</td>
<td>Cmd + ]</td>
</tr>
<tr>
<td>Switch to next <i>larger</i> zoom level in windowed mode,
</br>toggle stretching in fullscreen mode</td>
<td>Alt + =</td>
<td>Cmd + =</td>
</tr>
<tr>
<td>Switch to next <i>smaller</i> zoom level in windowed mode,
</br>toggle stretching in fullscreen mode</td>
<td>Alt + -</td>
<td>Cmd + -</td>
</tr>
<tr>
<td>Toggle windowed/fullscreen mode</td>
<td>Alt + Enter</td>
<td>Cmd + Enter</td>
</tr>
<tr>
<td>Toggle adapting display refresh rate to game frame rate
</br>
Note: Not available for macOS.</td>
<td>Alt + r</td>
<td>Cmd + r</td>
</tr>
<tr>
<td><i>Decrease</i> overscan in fullscreen mode</td>
<td>Shift + PageDown</td>
<td>Shift-Fn + Down arrow</td>
</tr>
<tr>
<td><i>Increase</i> overscan in fullscreen mode</td>
<td>Shift + PageUp</td>
<td>Shift-Fn + Up arrow</td>
</tr>
<tr>
<td>Move display <i>down</i> (uses "Display.VCenter")</td>
<td>Alt + PageDown</td>
<td>Cmd-Fn + Down arrow</td>
</tr>
<tr>
<td>Move display <i>up</i> (uses "Display.VCenter")</td>
<td>Alt + PageUp</td>
<td>Cmd-Fn + Up arrow</td>
</tr>
<tr>
<td>Toggle aspect ratio correct scaling</td>
<td>Control + c</td>
<td>Control + c</td>
</tr>
<tr>
<td><i>Decrease</i> vertical display size</td>
<td>Shift-Alt + PageUp</td>
<td>Shift-Cmd-Fn + Up arrow</td>
</tr>
<tr>
<td><i>Increase</i> vertical display size</td>
<td>Shift-Alt + PageDown</td>
<td>Shift-Cmd-Fn + Down arrow</td>
</tr>
<tr>
<td>Switch to <i>previous</i> display format (NTSC/PAL/SECAM etc.)</td>
<td>Shift-Control + f</td>
<td>Shift-Control + f</td>
</tr>
<tr>
<td>Switch to <i>next</i> display format (NTSC/PAL/SECAM etc.)</td>
<td>Control + f</td>
<td>Control + f</td>
</tr>
<tr>
<td>Toggle display interpolation</td>
<td>Control + i</td>
<td>Control + i</td>
</tr>
<tr>
<td colspan="3"><center><font size="-1">
These settings can also be changed using <a href="#GlobalKeys"><b>Global Keys</a></font></center>
</td>
</tr>
</table>
<p><b>Palettes Keys (can be remapped)</b></p>
<table BORDER=2 cellpadding=4>
<tr>
<th>Function</th>
<th>Key (Standard)</th>
<th>Key (macOS)</th>
</tr>
<tr>
<td>Select <i>previous</i> palette (Standard/z26/User/Custom)</td>
<td>Shift-Control + p</td>
<td>Shift-Control + p</td>
</tr>
<tr>
<td>Select <i>next</i> palette (Standard/z26/User/Custom)</td>
<td>Control + p</td>
<td>Control + p</td>
</tr>
<tr>
<td>Select <i>previous</i> palette attribute</td>
<td>Shift-Alt + 9</td>
<td>Shift-Cmd + 9</td>
</tr>
<tr>
<td>Select <i>next</i> palette attribute</td>
<td>Alt + 9</td>
<td>Cmd + 9</td>
</tr>
<tr>
<td><i>Decrease</i> selected palette attribute</td>
<td>Shift-Alt + 0</td>
<td>Shift-Cmd + 0</td>
</tr>
<tr>
<td><i>Increase</i> selected palette attribute</td>
<td>Alt + 0</td>
<td>Cmd + 0</td>
</tr>
<tr>
<td colspan="3"><center><font size="-1">
These settings can also be changed using <a href="#GlobalKeys"><b>Global Keys</a></font></center>
</td>
</tr>
</table>
<p><b>TV effects Keys (can be remapped)</b></p>
<table BORDER=2 cellpadding=4>
<tr>
<th>Function</th>
<th>Key (Standard)</th>
<th>Key (macOS)</th>
</tr>
<tr>
<td>Select <i>previous</i> TV effects preset</td>
<td>Shift-Alt + 1</td>
<td>Shift-Cmd + 1</td>
</tr>
<tr>
<td>Select <i>next</i> TV effects preset</td>
<td>Alt + 1</td>
<td>Cmd + 1</td>
</tr>
<tr>
<td>Select <i>previous</i> 'Custom' mode attribute (*)</td>
<td>Shift-Alt + 2</td>
<td>Shift-Cmd + 2</td>
</tr>
<tr>
<td>Select <i>next</i> 'Custom' mode attribute (*)</td>
<td>Alt + 2</td>
<td>Cmd + 2</td>
</tr>
<tr>
<td><i>Decrease</i> 'Custom' selected attribute value (*)</td>
<td>Shift-Alt + 3</td>
<td>Shift-Cmd + 3</td>
</tr>
<tr>
<td><i>Increase</i> 'Custom' selected attribute value (*)</td>
<td>Alt + 3</td>
<td>Cmd + 3</td>
</tr>
<tr>
<td>Toggle 'phosphor' mode</td>
<td>Alt + p</td>
<td>Cmd + p</td>
</tr>
<tr>
<td><i>Decrease</i> 'phosphor' blend</td>
<td>Shift-Alt + 4</td>
<td>Shift-Cmd + 4</td>
</tr>
<tr>
<td><i>Increase</i> 'phosphor' blend</td>
<td>Alt + 4</td>
<td>Cmd + 4</td>
</tr>
<tr>
<td><i>Decrease</i> scanline intensity</td>
<td>Shift-Alt + 5</td>
<td>Shift-Cmd + 5</td>
</tr>
<tr>
<td><i>Increase</i> scanline intensity</td>
<td>Alt + 5</td>
<td>Cmd + 5</td>
</tr>
<tr>
<td colspan="3"><center><font size="-1">
These settings can also be changed using <a href="#GlobalKeys"><b>Global Keys</a></font></center>
</td>
</tr>
<tr>
<td colspan="3"><center><font size="-1">
Items marked as (*) will also switch to 'Custom' mode</font></center></td>
</tr>
</table>
<a name="DeveloperKeys"></a>
<p><b>Developer Keys (can be remapped)</b></p>
<table BORDER=2 cellpadding=4>
<tr>
<th>Function</th>
<th>Key (Standard)</th>
<th>Key (macOS)</th>
</tr>
<tr>
<td>Toggle frame stats</br>(scanline count/FPS/BS type etc.)</td>
<td>Alt + L</td>
<td>Cmd + L</td>
</tr>
<tr>
<td>Toggle TIA Player0 object</td>
<td>Alt + z</td>
<td>Cmd + z</td>
</tr>
<tr>
<td>Toggle TIA Player1 object</td>
<td>Alt + x</td>
<td>Cmd + x</td>
</tr>
<tr>
<td>Toggle TIA Missile0 object</td>
<td>Alt + c</td>
<td>Cmd + c</td>
</tr>
<tr>
<td>Toggle TIA Missile1 object</td>
<td>Alt + v</td>
<td>Cmd + v</td>
</tr>
<tr>
<td>Toggle TIA Ball object</td>
<td>Alt + b</td>
<td>Cmd + b</td>
</tr>
<tr>
<td>Toggle TIA Playfield object</td>
<td>Alt + n</td>
<td>Cmd + n</td>
</tr>
<tr>
<td>Toggle all TIA objects</td>
<td>Alt + Comma</td>
<td>Cmd + Comma</td>
</tr>
<tr>
<td>Toggle TIA Player0 collisions</td>
<td>Shift-Alt + z</td>
<td>Shift-Cmd + z</td>
</tr>
<tr>
<td>Toggle TIA Player1 collisions</td>
<td>Shift-Alt + x</td>
<td>Shift-Cmd + x</td>
</tr>
<tr>
<td>Toggle TIA Missile0 collisions</td>
<td>Shift-Alt + c</td>
<td>Shift-Cmd + c</td>
</tr>
<tr>
<td>Toggle TIA Missile1 collisions</td>
<td>Shift-Alt + v</td>
<td>Shift-Cmd + v</td>
</tr>
<tr>
<td>Toggle TIA Ball collisions</td>
<td>Shift-Alt + b</td>
<td>Shift-Cmd + b</td>
</tr>
<tr>
<td>Toggle TIA Playfield collisions</td>
<td>Shift-Alt + n</td>
<td>Shift-Cmd + n</td>
</tr>
<tr>
<td>Toggle all TIA collisions</td>
<td>Shift-Alt + Comma</td>
<td>Shift-Cmd + Comma</td>
</tr>
<tr>
<td>Toggle TIA 'Fixed Debug Colors' mode</td>
<td>Alt + .</td>
<td>Cmd + .</td>
</tr>
<tr>
<td>Toggle PAL color-loss effect</td>
<td>Control + L</td>
<td>Control + L</td>
</tr>
<tr>
<td>Toggle TV 'Jitter' effect</td>
<td>Alt + j</td>
<td>Cmd + j</td>
</tr>
<tr>
<td colspan="3"><center><font size="-1">
These settings can also be changed using <a href="#GlobalKeys"><b>Global Keys</a></font></center>
</td>
</tr>
</table>
<p><b><a name="GlobalKeys">Global Keys</a> (can be remapped)</b></p>
<p>These keys allow selecting and changing settings without having to remember the
dedicated keys. They keys are grouped by Audio & Video and Debug settings.</p>
<table BORDER=2 cellpadding=4>
<tr>
<th>Function</th>
<th>Key (Standard)</th>
<th>Key (macOS)</th>
</tr>
<tr>
<td>Select <i>previous</i> setting group</td>
<td>Control + End</td>
<td>Control-Fn + Left arrow</td>
</tr>
<tr>
<td>Select <i>next</i> setting group</td>
<td>Control + Home</td>
<td>Control-Fn + Right arrow</td>
</tr>
<tr>
<td>Select <i>previous</i> setting</td>
<td>End</td>
<td>Fn + Left arrow</td>
</tr>
<tr>
<td>Select <i>next</i> setting</td>
<td>Home</td>
<td>Fn + Right arrow</td>
</tr>
<tr>
<td><i>Decrease</i> current setting</td>
<td>PageDown</td>
<td>Fn + Down arrow</td>
</tr>
<tr>
<td><i>Increase</i> current setting
<td>PageUp</td>
<td>Fn + Up arrow</td>
</tr>
</table>
<p>Notes:
<ul>
<li>Only available if UI messages are enabled.</li>
<li>Currently not available settings are automatically skipped.</li>
<li>If a setting was selected via dedicated key, its value can also be changed with the
global keys.</li>
</ul>
</p>
<p><b>Other Emulation Keys (can be remapped)</b></p>
<table BORDER=2 cellpadding=4>
<tr>
<th>Function</th>
<th>Key (Standard)</th>
<th>Key (macOS)</th>
</tr>
<tr>
<td>Load <i>previous</i> game in ROM (multicart ROM, TIA mode)</td>
<td>Shift-Control + r</td>
<td>Shift-Control + r</td>
</tr>
<tr>
<td>Reload current ROM (singlecart ROM, TIA mode)<br>
Load <i>next</i> game in ROM (multicart ROM, TIA mode)</td>
<td>Control + r</td>
<td>Control + r</td>
</tr>
<tr>
<td>Reload ROM listing (ROM launcher mode)</td>
<td>Control + r</td>
<td>Control + r</td>
</tr>
<tr>
<td>Emulate 'frying' effect (TIA mode)</td>
<td>Backspace</td>
<td>Backspace</td>
</tr>
<tr>
<td>Go to parent directory (UI mode)</td>
<td>Backspace</td>
<td>Backspace</td>
</tr>
<tr>
<td><i>Decrease</i> emulation speed (disables 'Turbo' mode)</td>
<td>Shift-Control + s</td>
<td>Shift-Control + s</td>
</tr>
<tr>
<td><i>Increase</i> emulation speed (disables 'Turbo' mode)</td>
<td>Control + s</td>
<td>Control + s</td>
</tr>
<tr>
<td>Toggle 'Turbo' mode (maximum emulation speed)</td>
<td>Control + t</td>
<td>Control + t</td>
</tr>
<tr>
<td><i>Decrease</i> autofire rate</td>
<td>Shift-Control + a</td>
<td>Shift-Control + a</td>
</tr>
<tr>
<td><i>Increase</i> autofire rate</td>
<td>Control + a</td>
<td>Control + a</td>
</tr>
<tr>
<td>Switch mouse between controller emulation modes</br>(see <b><a href="#Controller">Controller Properties</a></b>)</td>
<td>Control + 0</td>
<td>Control + 0</td>
</tr>
<tr>
<td>Toggle grab mouse</td>
<td>Control + g</td>
<td>Control + g</td>
</tr>
<tr>
<td>Swap Stelladaptor/2600-daptor port ordering</td>
<td>Control + 1</td>
<td>Control + 1</td>
</tr>
<tr>
<td>Save continuous PNG snapshots</br>(per interval defined in <a href="#Snapshots"><b>Snapshot Settings</b></a>)</td>
<td>Control-Alt + s</td>
<td>Control-Cmd + s</td>
</tr>
<tr>
<td>Save continuous PNG snapshots (every frame)</td>
<td>Shift-Control-Alt + s</td>
<td>Shift-Control-Cmd + s</td>
</tr>
<tr>
<td>Toggle 'Time Machine' mode</td>
<td>Alt + t</td>
<td>Cmd + t</td>
</tr>
<tr>
<td>Enter/Exit the <a href="#TimeMachine"><b>Time Machine</b></a> dialog</td>
<td>Shift + t to enter, Shift + t/Escape to exit and continue with emulation</td>
<td>Shift + t to enter, Shift + t/Escape to exit and continue with emulation</td>
</tr>
<tr>
<td>Playback the <a href="#TimeMachine"><b>Time Machine</b></a> from current state (without sound, from the TM dialog only)</td>
<td>Shift</td>
<td>Shift</td>
</tr>
<tr>
<td>Start/Stop playback (exist/enters the <a href="#TimeMachine"><b>Time Machine</b></a> dialog)</td>
<td>Shift + Space</td>
<td>Shift + Space</td>
</tr>
<tr>
<td>Rewind by one state (enters the <a href="#TimeMachine"><b>Time Machine</b></a> dialog)</td>
<td>Alt + Left arrow</td>
<td>Cmd + Left arrow</td>
</tr>
<tr>
<td>Rewind by 10 states (enters the <a href="#TimeMachine"><b>Time Machine</b></a> dialog)</td>
<td>Shift-Alt + Left arrow</td>
<td>Shift-Cmd + Left arrow</td>
</tr>
<tr>
<td>Rewind all states (enters the <a href="#TimeMachine"><b>Time Machine</b></a> dialog)</td>
<td>Alt + Down arrow</td>
<td>Cmd + Down arrow</td>
</tr>
<tr>
<td>Unwind by one state (enters the <a href="#TimeMachine"><b>Time Machine</b></a> dialog)</td>
<td>Alt + Right arrow</td>
<td>Cmd + Right arrow</td>
</tr>
<tr>
<td>Unwind by 10 states (enters the <a href="#TimeMachine"><b>Time Machine</b></a> dialog)</td>
<td>Shift-Alt + Right arrow</td>
<td>Shift-Cmd + Right arrow</td>
</tr>
<tr>
<td>Unwind all states (enters the <a href="#TimeMachine"><b>Time Machine</b></a> dialog)</td>
<td>Alt + Up arrow</td>
<td>Cmd + Up arrow</td>
</tr>
</table>
<p><b>UI Keys in Text Editing areas (cannot be remapped)</b></p>
<table BORDER=2 cellpadding=4>
<tr><th>Key</th><th>Editor Function</th></tr>
<tr><td>Home, Control + a</td><td>Move cursor to beginning of line</td></tr>
<tr><td>End, Control + e</td><td>Move cursor to end of line</td></tr>
<tr><td>Delete, Control + d</td><td>Remove character to right of cursor</td></tr>
<tr><td>Backspace</td><td>Remove character to left of cursor</td></tr>
<tr><td>Control + k</td><td>Remove all characters from cursor to end of line</td></tr>
<tr><td>Control + u</td><td>Remove all characters from cursor to beginning of line</td></tr>
<tr><td>Control + w</td><td>Remove entire word to left of cursor</td></tr>
<tr><td>Control + Left arrow</td><td>Move cursor to beginning of word to the left</td></tr>
<tr><td>Control + Right arrow</td><td>Move cursor to beginning of word to the right</td></tr>
<tr><td>Control + c, Control + Insert</td><td>Copy entire line to clipboard</td></tr>
<tr><td>Control + v, Shift + Insert</td><td>Paste clipboard contents</td></tr>
<tr><td>Control + x, Shift + Delete</td><td>Cut entire line to clipboard</td></tr>
</table>
</blockquote></br>
<h2><b><a name="ControlMap">Controller Map</a></b></h2>
<blockquote>
<p>Some Atari (virtual) controllers are simulated with more than one computer controller, and
there are several special cases where controllers are active in certain modes only, as the table
below shows. Items marked as <b>(+ extra)</b> indicate that the computer controller may not have
enough buttons/axes etc. to fully emulate the device, so extra functionality must be mapped to other
controllers.</p>
<table BORDER=2 cellpadding=4>
<tr>
<th>&nbsp;</th>
<th colspan="5">Computer</th>
</tr>
<tr>
<th>Virtual<br>Controller</th>
<th>Keyboard</th>
<th>Joystick</th>
<th>Mouse<br>(auto mode)</th>
<th>Mouse<br>(specific axis)</th>
<th>Stelladaptor/<br>2600-daptor</th>
</tr>
<tr>
<th> Joystick</th>
<td> &#x2713;</td>
<td> &#x2713;</td>
<td> &#x2713;</td>
<td> &#x2715;</td>
<td> &#x2713;</td>
</tr>
<tr>
<th> Paddles</th>
<td> &#x2713;</td>
<td> &#x2713;</td>
<td> &#x2713;</td>
<td> &#x2713;</td>
<td> &#x2713;</td>
</tr>
<tr>
<th> Booster</th>
<td> &#x2713;</td>
<td> &#x2713;</td>
<td> &#x2713; (+ extra)</td>
<td> &#x2715;</td>
<td> &#x2713; (+ extra)</td>
</tr>
<tr>
<th> Genesis</th>
<td> &#x2713;</td>
<td> &#x2713; (+ extra)</td>
<td> &#x2713;</td>
<td> &#x2715;</td>
<td> &#x2715;</td>
</tr>
<tr>
<th> Keyboard</th>
<td> &#x2713;</td>
<td> &#x2713; (+ extra)</td>
<td> &#x2715;</td>
<td> &#x2715;</td>
<td> &#x2713; (2600-daptor II)</td>
</tr>
<tr>
<th> Driving</th>
<td> &#x2713;</td>
<td> &#x2713;</td>
<td> &#x2713;</td>
<td> &#x2715;</td>
<td> &#x2713;</td>
</tr>
<tr>
<th> Trackball/Mouse</th>
<td> &#x2715;</td>
<td> &#x2715;</td>
<td> &#x2713;</td>
<td> &#x2713; (axis ignored)</td>
<td> &#x2713;</td>
</tr>
<tr>
<th> CompuMate</th>
<td> &#x2713;</td>
<td> &#x2715;</td>
<td> &#x2715;</td>
<td> &#x2715;</td>
<td> &#x2715;</td>
</tr>
<tr>
<th> Light Gun</th>
<td> &#x2715;</td>
<td> &#x2715;</td>
<td> &#x2713;</td>
<td> &#x2713; (axis ignored)</td>
<td> &#x2715;</td>
</tr>
<tr>
<th> Mindlink</th>
<td> &#x2715;</td>
<td> &#x2715;</td>
<td> &#x2713;</td>
<td> &#x2713; (axis ignored)</td>
<td> &#x2715;</td>
</tr>
<tr>
<th> AtariVox</th>
<td> N/A</td>
<td> N/A</td>
<td> N/A</td>
<td> N/A</td>
<td> voice (2600-daptor II)</td>
</tr>
<tr>
<th> SaveKey</th>
<td> N/A</td>
<td> N/A</td>
<td> N/A</td>
<td> N/A</td>
<td> N/A</td>
</tr>
</table>
</blockquote></br>
<br><br>
<p><h2>
<a name="TimeMachine">Stella's 'Time Machine'</a></h2>
<blockquote>
<p>A special feature of Stella is the 'Time Machine' mode. In this mode, Stella
automatically creates savestates in regular, user-defined intervals. At any time,
the user can interrupt the current emulation and navigate back and forth
within the saved timeline.
This can be done either by using the Time Machine hotkeys described in
<a href="#Hotkeys"><b>Hotkeys</b> - Other Keys</a> or by using the Time Machine
dialog. This dialog is automatically entered when using one of the Time Machine
hotkeys. The hotkeys continue to function within the dialog.</p>
<p><b>Time Machine</b> dialog:</p>
<td><img src="graphics/timemachine.png"></td>
<p>The dialog items are explained in the following two tables.</p>
<p><b>Top row (left to right)</b></p>
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Description</th></tr>
<tr><td>Current state</td><td>Shows the currently loaded state's number</td></tr>
<tr><td>'Timeline' slider</td><td>Shows the position of the current state in the
recorded timeline. A state can be selected by dragging the slider with the mouse.
To visualize state compression, small marks split the timeline into five, equally
sized state number intervals.</td></tr>
<tr><td>Total states</td><td>Shows the total number of save states in the
Time Machine</td></tr>
</table>
<p><b>Bottom row (left to right)</b></p>
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Description</th></tr>
<tr><td>Current time</td><td>Shows the time of the currently selected state,
relative to the first one</td></tr>
<tr><td>'Start/Stop' button</td><td>Starts or stops the Time Machine</td></tr>
<tr><td>'Exit' button</td><td>Exits the dialog and continues emulation, starting at current state</td></tr>
<tr><td>'Rewind All' button</td><td>Navigates back to the begin of the timeline</td></tr>
<tr><td>'Rewind One' button</td><td>Navigates back by one state</td></tr>
<tr><td>'Playback' button</td><td>Starts playback, starting at the current state (with sound disabled)</td></tr>
<tr><td>'Unwind One' button</td><td>Navigates forward by one state</td></tr>
<tr><td>'Unwind All' button</td><td>Navigates forward to the end of the timeline</td></tr>
<tr><td>'Save All' button</td><td>Saves all Time Machine states to disk</td></tr>
<tr><td>'Load All' button</td><td>Loades all states from disk into Time Machine</td></tr>
<tr><td>Navigation info</td><td>Informs about the interval of the user's last
Time Machine navigation. The interval can vary if the timeline is compressed.</td></tr>
<tr><td>Total time</td><td>Shows the total time covered by the save states
(aka 'Horizon')</td></tr>
</table>
<br>
<p>The 'Time Machine' mode can be configured by the user. For details see
<a href="#Debugger"><b>Developer Options</b> - Time Machine</a></h2> tab.</p>
</blockquote></br>
<!-- ///////////////////////////////////////////////////////////////////////// -->
<br>
<p><h1>
<a name="Advanced">Advanced Configuration</a></h1>
<hr>
<p>The default options in Stella are meant to cater to as many situations as
possible. As such, you may never need to change many of its options. However,
Stella is very configurable, and if you want to change its behaviour in some way,
there's likely a configuration option to do so. The remainder of this (lengthy)
section details every configurable option.</p>
<h2><b><a name="CommandLine">Using the Command Line</a></b></h2>
<blockquote>
<p>In addition to the built in ROM launcher, Stella can also be used from the
command line (assuming your operating system has a command line).</p>
<p>To run Stella from the command line, use the following format:</p>
<pre> stella [options ...] ROM_FILENAME</pre>
<p><b>Options</b> ('0' or 'false' indicates false, '1' or 'true' indicates true,
others are self-explanatory):</p>
<table BORDER=2>
<tr>
<th>Argument</th>
<th>Description</th>
</tr>
<tr>
<td><pre>-video &lt;direct3d|opengl|opengles2|opengles|software&gt;</pre></td>
<td>Use the given rendering backend (where applicable); default is the best available
mode detected.</td>
</tr>
<tr>
<td><pre>-vsync &lt;1|0&gt;</pre></td>
<td>Synchronize screen updates to the vertical blank period.
This can result in smoother updates, and eliminate tearing.</td>
</tr>
<tr>
<td><pre>-fullscreen &lt;1|0&gt;</pre></td>
<td>Enable fullscreen mode.</td>
</tr>
<tr>
<td><pre>-center &lt;1|0&gt;</pre></td>
<td>Center all windows (if possible).</td>
</tr>
<tr>
<td><pre>-windowedpos &lt;XxY&gt;</pre></td>
<td>Set the window position in windowed emulator mode.</td>
</tr>
<tr>
<td><pre>-display &lt;number&gt;</pre></td>
<td>Set the display for Stella's emulator.</td>
</tr>
<tr>
<td><pre>-palette &lt;standard|z26|user|custom&gt;</pre></td>
<td>Set the palette to either normal Stella, the one used in the z26
emulator, a user-defined palette, or a custom palette generated
from user-defined parameters.</td>
</tr>
<tr>
<td><pre>-pal.phase_ntsc &lt;number&gt;</pre></td>
<td>Adjust phase shift of 'custom' NTSC palette.</td>
</tr>
<tr>
<td><pre>-pal.phase_pal &lt;number&gt;</pre></td>
<td>Adjust phase shift of 'custom' PAL palette.</td>
</tr>
<tr>
<td><pre>-pal.red_scale &lt;number&gt;</pre></td>
<td>Adjust red scale of 'custom' palette (range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-pal.red_shift &lt;number&gt;</pre></td>
<td>Adjust red shift of 'custom' palette (range -22.5 to 22.5).</td>
</tr>
<tr>
<td><pre>-pal.green_scale &lt;number&gt;</pre></td>
<td>Adjust green scale of 'custom' palette (range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-pal.green_shift &lt;number&gt;</pre></td>
<td>Adjust green shift of 'custom' palette (range -22.5 to 22.5).</td>
</tr>
<tr>
<td><pre>-pal.blue_scale &lt;number&gt;</pre></td>
<td>Adjust blue scale of 'custom' palette (range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-pal.blue_shift &lt;number&gt;</pre></td>
<td>Adjust blue shift of 'custom' palette (range -22.5 to 22.5).</td>
</tr>
<tr>
<td><pre>-pal.hue &lt;number&gt;</pre></td>
<td>Adjust hue of current palette (range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-pal.saturation &lt;number&gt;</pre></td>
<td>Adjust saturation of current palette (range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-pal.contrast &lt;number&gt;</pre></td>
<td>Adjust contrast of current palette (range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-pal.brightness &lt;number&gt;</pre></td>
<td>Adjust brightness of current palette (range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-pal.gamma &lt;number&gt;</pre></td>
<td>Adjust gamma of current palette (range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-speed &lt;number&gt;</pre></td>
<td>Control the emulation speed (as a percentage, 10 - 1000).</td>
</tr>
<tr>
<td><pre>-turbo &lt;1|0&gt;</pre></td>
<td>Enable 'Turbo' mode for maximum emulation speed.</td>
</tr>
<tr>
<td><pre>-uimessages &lt;1|0&gt;</pre></td>
<td>Enable or disable display of message in the UI. Note that messages
indicating serious errors override this setting, and are always
shown.</td>
</tr>
<tr>
<td><pre>-audio.enabled &lt;1|0&gt;</pre></td>
<td>Enable or disable sound generation.</td>
</tr>
<tr>
<td><pre>-audio.volume &lt;0 - 100&gt;</pre></td>
<td>Set the volume.</td>
</tr>
<tr>
<td><pre>-audio.device &lt;number&gt;</pre></td>
<td>Set the audio device (0 = default).</td>
</tr>
<tr>
<td><pre>-audio.preset &lt;1 - 5&gt;</pre></td>
<td>Set an audio preset. Numbers in sequence represent presets for
'custom', 'low quality, medium lag', 'high quality, medium lag',
'high quality, low lag' and 'ultra quality, minimal lag'.</td>
</tr>
<tr>
<td><pre>-audio.fragment_size &lt;128|256|512|1024|2048|4096&gt;</pre></td>
<td>Set the number of samples in a single fragment processed by the audio driver.</td>
</tr>
<tr>
<td><pre>-audio.sample_rate &lt;44100|48000|96000&gt;</pre></td>
<td>Set sound sample output frequency.</td>
</tr>
<tr>
<td><pre>-audio.resampling_quality &lt;1|2|3&gt;</pre></td>
<td>Set resampling quality to low (1), high (2) or ultra (3).</td>
</tr>
<tr>
<td><pre>-audio.headroom &lt;0 - 20&gt;</pre></td>
<td>Set number of additional half-frames to prebuffer.</td>
</tr>
<tr>
<td><pre>-audio.buffer_size &lt;0 - 20&gt;</pre></td>
<td>Set maximum number of additional half-frames to buffer.</td>
</tr>
<tr>
<td><pre>-audio.stereo &lt;1|0&gt;</pre></td>
<td>Enable or disable stereo mode for all ROMs.</td>
</tr>
<tr>
<td><pre>-audio.dpc_pitch &lt;10000 - 30000&gt;</pre></td>
<td>Set the pitch of Pitfall II music.</td>
</tr>
<tr>
<td><pre>-tia.zoom &lt;zoom&gt;</pre></td>
<td>Use the specified zoom level (integer) while in TIA/emulation mode.
</td>
</tr>
<tr>
<td><pre>-tia.vsizeadjust &lt;-5 - 5&gt;</pre></td>
<td>Adjust the display height of the TIA image
</td>
</tr>
<tr>
<td><pre>-tia.inter &lt;1|0&gt;</pre></td>
<td>Use interpolation for the TIA image (results in blending/smoothing
of the image).</td>
</tr>
<tr>
<td><pre>-tia.fs_stretch &lt;1|0&gt;</pre></td>
<td>Stretch TIA image completely while in fullscreen mode, vs. keeping the correct
aspect ratio.</td>
</tr>
<tr>
<td><pre>-tia.fs_refresh &lt;1|0&gt;</pre></td>
<td>While in fullscreen mode, adapt the display's refresh rate to the game's frame rate
to minimize judder.</br>
Note: Not available for macOS.</td>
</tr>
<tr>
<td><pre>-tia.fs_overscan &lt;0 - 10&gt;</pre></td>
<td>Add overscan to TIA image while in fullscreen mode</td>
</tr>
<tr>
<td><pre>-tia.dbgcolors &lt;roygbp&gt;</pre></td>
<td>Assign the colours (R)ed, (O)range, (Y)ellow, (G)reen, (B)lue and (P)urple
to each graphical register P0/M0/P1/M1/PF/BL, respectively. Currently,
these change be changed around to apply different colours to the
respective register.
</td>
</tr>
<tr>
<td><pre>-tia.correct_aspect &lt;1|0&gt;</pre></td>
<td>Enable aspect ratio correct scaling.</td>
</tr>
<tr>
<td><pre>-tv.filter &lt;0 - 5&gt;</pre></td>
<td>Blargg TV effects, 0 is disabled, next numbers in
sequence represent presets for 'RGB', 'S-Video', 'Composite', 'Bad Adjust'
and 'Custom' modes.</td>
</tr>
<tr>
<td><pre>-tv.sharpness &lt;number&gt;</pre></td>
<td>Blargg TV effects 'sharpness' (only available in custom mode,
range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-tv.resolution &lt;number&gt;</pre></td>
<td>Blargg TV effects 'resolution' (only available in custom mode,
range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-tv.artifacts &lt;number&gt;</pre></td>
<td>Blargg TV effects 'artifacts' (only available in custom mode,
range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-tv.fringing &lt;number&gt;</pre></td>
<td>Blargg TV effects 'fringing' (only available in custom mode,
range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-tv.bleed &lt;number&gt;</pre></td>
<td>Blargg TV effects 'bleed' (only available in custom mode,
range -1.0 to 1.0).</td>
</tr>
<tr>
<td><pre>-tv.phosphor &lt;always|byrom&gt;</pre></td>
<td>Determine how phosphor mode is enabled. If 'always', then the
ROM properties entry is ignored, and phosphor mode is always turned
on. Otherwise, the ROM properties determine whether phosphor mode
is used for each ROM.
</td>
</tr>
<tr>
<td><pre>-tv.phosblend &lt;0 - 100&gt;</pre></td>
<td>Enable phosphor blending level; 0 implies no mixing, and 100
is full mixing (not recommended). Note that this doesn't actually
enable phosphor mode; that is done for each ROM in the ROM properties.
Higher blend values will intensify the phosphor effect. Depending on your
display and personal preferences, the optimal default for you may vary.
Slow LCDs (especially for office use) may only need a low blend of
around 30, while fast switching gamer LCDs may need about 70 to look
similar to a CRT.
</td>
</tr>
<tr>
<td><pre>-tv.scanlines &lt;0 - 100&gt;</pre></td>
<td>Set TV effects scanline intensity, where 0 means completely off. Note: No scanlines in 1x mode snapshots.</td>
</tr>
<tr>
<td><pre>-cheat &lt;code&gt;</pre></td>
<td>Use the specified cheatcode (see <a href="#Cheats"><b>Cheat</b></a> section for description).</td>
</tr>
<tr>
<td><pre>-loglevel &lt;0|1|2&gt;</pre></td>
<td>Indicate level of logging to perform while the application is running. Zero completely disables logging (except for serious errors), while the remaining numbers show increasingly more detail.</td>
</tr>
<tr>
<td><pre>-logtoconsole &lt;1|0&gt;</pre></td>
<td>Indicate that logged output should be printed to the console/command line as it's being collected. An internal log will still be kept, and the amount of logging is still controlled by 'loglevel'.</td>
</tr>
<tr>
<td><pre>-joydeadzone &lt;number&gt;</pre></td>
<td>Set the joystick axis deadzone area for analog joysticks/gamepads.
All values within the deadzone are treated as zero-axis values,
while only those values outside are registered as valid input.
Accepts a number from 0 - 29, and uses the formula
3200 + number * 1000. So the possible deadzone values
range from 3200 to 32200.</td>
</tr>
<tr>
<td><pre>-psense &lt;number&gt;</pre></td>
<td>Sensitivity for emulation of paddles when using analog paddles.
Valid range of values is from 1 to 30, with larger numbers causing
faster movement.</td>
</tr>
<tr>
<td><pre>-dejitter.base &lt;0 - 10&gt;</pre></td>
<td>Strength of paddle input averaging.</td>
</tr>
<tr>
<td><pre>-dejitter.diff &lt;0 - 10&gt;</pre></td>
<td>Impact of fast paddle movement on input averaging.</td>
</tr>
<tr>
<td><pre>-dcsense &lt;number&gt;</pre></td>
<td>Sensitivity for emulation of driving controllers when using a mouse.
Valid range of values is from 1 to 20, with larger numbers causing
faster movement.</td>
</tr>
<tr>
<td><pre>-autofirerate &lt;0 - 30&gt;</pre></td>
<td>Automatic trigger rate of the fire buttons in Hz (0 = disabled)</td>
</tr>
<tr>
<td><pre>-joyallow4 &lt;1|0&gt;</pre></td>
<td>Allow all 4 directions on a joystick to be pressed
simultaneously.</td>
</tr>
<tr>
<td><pre>-modcombo &lt;1|0&gt;</pre></td>
<td>Use modifier(Shift/Alt/Control) + x key combos. This is normally enabled,
since the 'Quit' command is tied to 'Control + q'. However, there are times
when you want to disable them.</br>
E.g. a 2-player game is using either the 'f' or 'r' keys for movement,
and pressing Control (for Fire) will perform an unwanted action
associated with 'Control + r' or 'Control + f' default keys.</td>
</tr>
<tr>
<td><pre>-saport &lt;lr|rl&gt;</pre></td>
<td>Determine how to enumerate the Stelladaptor/2600-daptor devices in the
order they are found: 'lr' means first is left port, second is right port,
'rl' means the opposite.</td>
</tr>
<tr>
<td><pre>-avoxport &lt;name&gt;</pre></td>
<td>Set the name of the serial port where an AtariVox is connected.</td>
</tr>
<tr>
<td><pre>-usemouse &lt;always|analog|never&gt;</pre></td>
<td>Use mouse as a controller as specified by ROM properties in specific case.
Always and never are self-explanatory, analog means only for analog-type devices
(paddles, trackball, etc.).</td>
</tr>
<tr>
<td><pre>-msense &lt;number&gt;</pre></td>
<td>Sensitivity for emulation of paddles when using a mouse.
Valid range of values is from 1 to 20, with larger numbers causing
faster movement.</td>
</tr>
<tr>
<td><pre>-tsense &lt;number&gt;</pre></td>
<td>Sensitivity for emulation of trackball controllers when using a mouse.
Valid range of values is from 1 to 20, with larger numbers causing
faster movement.</td>
</tr>
<tr>
<td><pre>-dsense &lt;number&gt;</pre></td>
<td>Sensitivity for emulation of paddles when using a digital device
(ie, joystick digital axis or button, keyboard key, etc.).
Valid range of values is from 1 to 20, with larger numbers causing
faster movement.</td>
</tr>
<tr>
<td><pre>-cursor &lt;0|1|2|3&gt;</pre></td>
<td>Set mouse cursor state in UI/emulation modes.</td>
</tr>
<tr>
<td><pre>-grabmouse &lt;1|0&gt;</pre></td>
<td>Lock the mouse cursor in the game window in emulation mode.</td>
</tr>
<tr>
<td><pre>-autoslot &lt;1|0&gt;</pre></td>
<td>Automatically change to the next available save state slot after
saving a ROM state file.</td>
</tr>
<tr>
<td><pre>-saveonexit &lt;none|current|all&gt;</pre></td>
<td>Automatically save no, current or all states when exiting emulation. The latter
also loads all states when entering emulation.</td>
</tr>
<tr>
<td><pre>-fastscbios &lt;1|0&gt;</pre></td>
<td>Disable Supercharger BIOS progress loading bars.</td>
</tr>
<tr>
<td><pre>-threads &lt;1|0&gt;</pre></td>
<td>Enable multi-threaded video rendering (may not improve performance on all systems).</td>
</tr>
<tr>
<td><pre>-snapsavedir &lt;path&gt;</pre></td>
<td>The directory to save snapshot files to.</td>
</tr>
<tr>
<td><pre>-snaploaddir &lt;path&gt;</pre></td>
<td>The directory to load ROM info viewer snaposhot files from.</td>
</tr>
<tr>
<td><pre>-snapname &lt;int|rom&gt;</pre></td>
<td>When saving snapshots, use either the internal database name or
the actual ROM filename.</td>
</tr>
<tr>
<td><pre>-sssingle &lt;1|0&gt;</pre></td>
<td>Generate single snapshot instead of many, overwriting
any previous snapshots.</td>
</tr>
<tr>
<td><pre>-ss1x &lt;1|0&gt;</pre></td>
<td>Ignore any scaling applied to the TIA image, and save
snapshot in unscaled (1x) mode.</td>
</tr>
<tr>
<td><pre>-ssinterval &lt;number&gt;</pre></td>
<td>Set the interval in seconds between taking snapshots in continuous snapshot mode (currently 1 - 10).</td>
</tr>
<tr>
<td><pre>-rominfo &lt;rom&gt;</pre></td>
<td>Display detailed information about the given ROM, and then exit
Stella.</td>
</tr>
<tr>
<td><pre>-listrominfo</pre></td>
<td>Print relevant contents of the Stella ROM database, one ROM per line,
and then exit Stella. This can be used for external frontends.</td>
</tr>
<tr>
<td><pre>-exitlauncher &lt;1|0&gt;</pre></td>
<td>Always exit to ROM launcher when exiting a ROM (normally, an exit to
launcher only happens when started with the launcher).</td>
</tr>
<tr>
<td><pre>-launcherpos &lt;XxY&gt;</pre></td>
<td>Set the window position in windowed ROM launcher mode.</td>
</tr>
<tr>
<td><pre>-launcherdisplay &lt;number&gt;</pre></td>
<td>Set the display for the ROM launcher.</td>
</tr>
<tr>
<td><pre>-launcherres &lt;WxH&gt;</pre></td>
<td>Set the size of the ROM launcher.</td>
</tr>
<tr>
<td><pre>-launcherfont &lt;small|low_medium|medium|large|large12|large14|large16&gt;</pre></td>
<td>Set the size of the font in the ROM launcher.</td>
</tr>
<tr>
<td><pre>-launcherroms &lt;1|0&gt;</pre></td>
<td>Specifies whether to show ROMs only (the default) or all
files in the ROM launcher.</td>
</tr>
<tr>
<td><pre>-romviewer &lt;float&gt;</pre></td>
<td>Hide ROM Info Viewer in ROM launcher mode (0) or use the
given zoom level.</br>
Note: The zoom level is converted into a percentage in the UI.</td>
</tr>
<tr>
<td><pre>-uipalette &lt;standard|classic|light|dark&gt;</pre></td>
<td>Use the specified palette for UI elements.</td>
</tr>
<tr>
<td><pre>-dialogfont &lt;small|low_medium|medium|large|large12|large14|large16&gt;</pre></td>
<td>Set the size of the font in the dialogs.</td>
</tr>
<tr>
<td><pre>-dialogpos &lt;0 - 4&gt;</pre></td>
<td>Set the position of dialogs within Stella windows (0 = center).</td>
</tr>
<tr>
<td><pre>-hidpi &lt;0|1&gt;</pre></td>
<td>Enable the HiDPI mode which scales the UI by a factor of two.</td>
</tr>
<tr>
<td><pre>-confirmexit &lt;0|1&gt;</pre></td>
<td>Display a popup when emulation is exited.</td>
</tr>
<tr>
<td><pre>-listdelay &lt;delay&gt;</pre></td>
<td>Set the amount of time to wait between treating successive
keypresses as a single word in file listings (value can range
from 300-1000). Use '0' to disable list-skipping completely.</td>
</tr>
<tr>
<td><pre>-mwheel &lt;lines&gt;</pre></td>
<td>Set the number of lines the mousewheel will scroll in the UI (1 - 10).</td>
</tr>
<tr>
<td><pre>-mdouble &lt;speed&gt;</pre></td>
<td>Set the mouse double click speed in the UI (100 - 900 ms).</td>
</tr>
<tr>
<td><pre>-ctrldelay &lt;delay&gt;</pre></td>
<td>Set the delay before controller input will start repeating in the UI (200 - 1000 ms).</td>
</tr>
<tr>
<td><pre>-ctrlrate &lt;rate&gt;</pre></td>
<td>Set the controller repeat rate in the UI (2 - 30 repeats/s).</td>
</tr>
<tr>
<td><pre>-romdir &lt;dir&gt;</pre></td>
<td>Set the path where the ROM launcher will start.</td>
</tr>
<tr>
<td><pre>-followlauncher &lt;0|1&gt;</pre></td>
<td>Make the start path follow ROM launcher navigation.</td>
</tr>
<tr>
<td><pre>-maxres &lt;WxH&gt;</pre></td>
<td>Useful for developers, this sets the maximum size of window that
can be created, allowing to simulate testing on 'smaller' systems.</td>
</tr>
<tr>
<td><pre>-basedir &lt;dir&gt;</pre></td>
<td>Override the base directory for all config files.</td>
</tr>
<tr>
<td><pre>-baseinappdir</pre></td>
<td>Override the base directory for all config files by attempting to use the application directory. For now this is only supported in Windows.</td>
</tr>
<tr>
<td><pre>-help</pre></td>
<td>Prints a help message describing these options, and then
exit Stella.</td>
</tr>
</table>
<a name="DeveloperCommandLine"></a>
<p>The following are useful to developers. Only use them if you know what
you're doing! Note that in all cases, the values supplied to the arguments
are <b>not</b> case sensitive.</p>
<table BORDER=2>
<tr>
<th>Argument</th>
<th>Description</th>
</tr>
<tr>
<td><pre>-dis.resolve &lt;1|0&gt;</pre></td>
<td>Try to differentiate between code vs. data sections in the
disassembler. See the <b>Debugger - <a href="debugger.html#DisassemblySettings">ROM Disassembly Settings</b></a> for more information.</td>
</tr>
<tr>
<td><pre>-dis.gfxformat &lt;2|16&gt;</pre></td>
<td>Set the base to use for displaying GFX sections in the disassembler.
</td>
</tr>
<tr>
<td><pre>-dis.showaddr &lt;1|0&gt;</pre></td>
<td>Show/hide opcode addresses in the disassembler.</td>
</tr>
<tr>
<td><pre>-dis.relocate &lt;1|0&gt;</pre></td>
<td>Relocate calls out of address range in the disassembler.</td>
</tr>
<tr>
<td><pre>-dbg.pos &lt;XxY&gt;</pre></td>
<td>Set the window position in windowed debugger mode.</td>
</tr>
<tr>
<td><pre>-dbg.display &lt;number&gt;</pre></td>
<td>Set the display for the debugger.</td>
</tr>
<tr>
<td><pre>-dbg.res &lt;WxH&gt;</pre></td>
<td>Set the size of the debugger window.</td>
</tr>
<tr>
<td><pre>-dbg.fontsize &lt;small|medium|large|&gt;</pre></td>
<td>Set the font size in the debugger window.</td>
</tr>
<tr>
<td><pre>-dbg.fontstyle &lt;0|1|2|3&gt;</pre></td>
<td>How to use bold fonts in the debugger window. '0' means all normal font,
'1' is bold labels only, '2' is bold non-labels only, '3' is all bold font.</td>
</tr>
<tr>
<td><pre>-dbg.ghostreadstrap &lt;1|0&gt;</pre></td>
<td>Debugger considers/ignores 'ghost' reads for trap addresses</td>
</tr>
<tr>
<td><pre>-dbg.uhex &lt;0|1&gt;</pre></td>
<td>Lower-/uppercase HEX display</td>
</tr>
<tr>
<td><pre>-break &lt;address&gt;</pre></td>
<td>Set a breakpoint at specified address.</td>
</tr>
<tr>
<td><pre>-debug</pre></td>
<td>Immediately jump to debugger mode when starting Stella.</td>
</tr>
<tr>
<td><pre>-holdjoy0 &lt;U,D,L,R,F&gt;</pre></td>
<td>Start the emulator with the left joystick direction/button held down
(ie, use 'UF' for up and fire). After entering the emulation, you will
have to press and release the direction again to release the event.</td>
</tr>
<tr>
<td><pre>-holdjoy1 &lt;U,D,L,R,F&gt;</pre></td>
<td>Start the emulator with the right joystick direction/button held down
(ie, use 'UF' for up and fire). After entering the emulation, you will
have to press and release the direction again to release the event.</td>
</tr>
<tr>
<td><pre>-holdselect</pre></td>
<td>Start the emulator with the Game Select switch held down. After entering
the emulation, you will have to press and release 'Select' to release the
event.</td>
</tr>
<tr>
<td><pre>-holdreset</pre></td>
<td>Start the emulator with the Game Reset switch held down. After entering
the emulation, you will have to press and release 'Reset' to release the
event.</td>
</tr>
<tr>
<td><pre>-bs &lt;type&gt;</pre></td>
<td>Set "Cart.Type" property. See the <a href="#Emulation"><b>Emulation Properties</b></a> section
for valid types.</td>
</tr>
<tr>
<td><pre>-type &lt;type&gt;</pre></td>
<td>Same as using -bs.</td>
</tr>
<tr>
<td><pre>-startbank &lt;bank&gt;</pre></td>
<td>Set "Cart.StartBank" property.</td>
</tr>
<tr>
<td><pre>-channels &lt;Mono|Stereo&gt;</pre></td>
<td>Set "Cart.Sound" property.</td>
</tr>
<tr>
<td><pre>-ld &lt;A|B&gt;</pre></td>
<td>Set "Console.LeftDiff" property.</td>
</tr>
<tr>
<td><pre>-rd &lt;A|B&gt;</pre></td>
<td>Set "Console.RightDiff" property.</td>
</tr>
<tr>
<td><pre>-tv &lt;Color|BW&gt;</pre></td>
<td>Set "Console.TVType" property.</td>
</tr>
<tr>
<td><pre>-sp &lt;Yes|No&gt;</pre></td>
<td>Set "Console.SwapPorts" property.</td>
</tr>
<tr>
<td><pre>-lc &lt;type&gt;</pre></td>
<td>Set "Controller.Left" property. See the <a href="#Controller"><b>Controller Properties</b></a>
section for valid types.</td>
</tr>
<tr>
<td><pre>-lq1 &lt;type&gt;</pre></td>
<td>Set "Controller.Left1" property for QuadTari. See the <a href="#Quadtari"><b>QuadTari Properties</b></a>
section for valid types.</td>
</tr>
<tr>
<td><pre>-lq2 &lt;type&gt;</pre></td>
<td>Set "Controller.Left2" property for QuadTari. See the <a href="#Quadtari"><b>QuadTari Properties</b></a>
section for valid types.</td>
</tr>
<tr>
<td><pre>-rc &lt;type&gt;</pre></td>
<td>Set "Controller.Right" property. See the <a href="#Controller"><b>Controller Properties</b></a>
section for valid types.</td>
</tr>
<tr>
<td><pre>-rq1 &lt;type&gt;</pre></td>
<td>Set "Controller.Right1" property for QuadTari. See the <a href="#Quadtari"><b>QuadTari Properties</b></a>
section for valid types.</td>
</tr>
<tr>
<td><pre>-rq2 &lt;type&gt;</pre></td>
<td>Set "Controller.Right2" property for QuadTari. See the <a href="#Quadtari"><b>QuadTari Properties</b></a>
section for valid types.</td>
</tr>
<tr>
<td><pre>-bc &lt;type&gt;</pre></td>
<td>Set both "Controller.Left" and "Controller.Right" properties.
See the <a href="#Controller"><b>Controller Properties</b></a> section for valid types.</td>
</tr>
<tr>
<td><pre>-aq &lt;type&gt;</pre></td>
<td>Set "Controller.Left1", "Controller.Left2", "Controller.Right1" and "Controller.Right2" properties for QuadTari.
See the <a href="#Quadtari"><b>QuadTari Properties</b></a> section for valid types.</td>
</tr>
<tr>
<td><pre>-cp &lt;Yes|No&gt;</pre></td>
<td>Set "Controller.SwapPaddles" property.</td>
</tr>
<tr>
<td><pre>-pxcenter &lt;-10..30&gt;</pre></td>
<td>Set "Controller.PaddlesXCenter" property.</td>
</tr>
<tr>
<td><pre>-pycenter &lt;-10..30&gt;</pre></td>
<td>Set "Controller.PaddlesYCenter" property.</td>
</tr>
<tr>
<td><pre>-ma &lt;Auto|XY&gt;</pre></td>
<td>Set "Controller.MouseAxis" property.
See the <a href="#Controller"><b>Controller Properties</b></a> section for valid types.</td>
</tr>
<tr>
<td><pre>-format &lt;format&gt;</pre></td>
<td>Set "Display.Format" property. See the <a href="#Emulation"><b>Emulation Properties</b></a> section
for valid formats.</td></td>
</tr>
<tr>
<td><pre>-vcenter &lt;number&gt;</pre></td>
<td>Set "Display.VCenter" property (-5..5).</td>
</tr>
<tr>
<td><pre>-pp &lt;Yes|No&gt;</pre></td>
<td>Set "Display.Phosphor" property.</td>
</tr>
<tr>
<td><pre>-ppblend &lt;number&gt;</pre></td>
<td>Set "Display.PPBlend" property, used for phosphor effect (0-100).
Default is whatever is specified for tv.phosblend.</td>
</tr>
</table>
<p>The following are almost all available in two sets, one for players (prefixed by "plr.") and one
for developers (prefixd by "dev."). Only use them if you know what you're doing! Note
that in all cases, the values supplied to the arguments are <b>not</b> case sensitive.</p>
<table BORDER=2>
<tr>
<th>Argument</th>
<th>Description</th>
</tr><tr>
<td><pre>-dev.settings &lt;1|0&gt;</pre></td>
<td>Select developer (1) or player (0) set.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;stats &lt;1|0&gt;</pre></td>
<td>Overlay console info on the TIA image during emulation.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;detectedinfo &lt;1|0&gt;</pre></td>
<td>Display detected settings info when a ROM is loaded.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;console &lt;2600|7800&gt;</pre></td>
<td>Select console for B/W and Pause key handling and RAM initialization.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;bankrandom &lt;1|0&gt;</pre></td>
<td>On reset, randomize the startup bank (only for selected bankswitch types).</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;ramrandom &lt;1|0&gt;</pre></td>
<td>On reset, either randomize all RAM content, or initialize with zero (console = 2600)/startup values (console = 7800) instead.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;cpurandom &lt;S,A,X,Y,P&gt;</pre></td>
<td>On reset, randomize the content of the specified CPU registers.</td>
</tr><tr>
<td><pre>-dev.tiadriven &lt;1|0&gt;</pre></td>
<td>Set unused TIA pins to be randomly driven high or low on a read/peek.
If disabled, use the last databus value for those pins instead.</td>
</tr><tr>
<td><pre>-dev.rwportbreak &lt;1|0&gt;</pre></td>
<td>Since the 2600 has no dedicated R/W line, different addresses are
used for RAM read or write access.</br>
If the code reads from such a write address, this causes an unwanted,
semi-random write to that address.</br>
When this option is enabled, such reads interrupt emulation and the
debugger is entered.</td>
</tr><tr>
<td><pre>-dev.wrportbreak &lt;1|0&gt;</pre></td>
<td>Same as above.</br>
If the code writes to such a read address, nothing happens. But a
developer should be made aware of it, because this indicates a problem
with the code.</br>
When this option is enabled, such writes interrupt emulation and the
debugger is entered.</td>
</tr><tr>
<td><pre>-dev.thumb.trapfatal &lt;1|0&gt;</pre></td>
<td>When enabled, this allows the Thumb ARM emulation to
throw an exception and enter the debugger on fatal errors. When disabled, such
fatal errors are simply logged, and emulation continues. Do not use this
unless you know exactly what you're doing, as it changes the behaviour as
compared to real hardware.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;eepromaccess &lt;1|0&gt;</pre></td>
<td>When enabled, each read or write access to the AtariVox/SaveKey EEPROM is
signalled by a message.</td>
</tr><tr>
<td><pre>-dev.tia.type &lt;standard|koolaidman|cosmicark|</br> pesco|quickstep|indy500|heman|custom&gt;</pre></td>
<td>Set emulated TIA type.</td>
</tr><tr>
<td><pre>-dev.tia.plinvphase &lt;1|0&gt;</pre></td>
<td>Enable/disable inverted HMOVE clock phase for players (Kool Aid Man glitch).</td>
</tr><tr>
<td><pre>-dev.tia.msinvphase &lt;1|0&gt;</pre></td>
<td>Enable/disable inverted HMOVE clock phase for missiles (Cosmic Ark stars glitch).</td>
</tr><tr>
<td><pre>-dev.tia.blinvphase &lt;1|0&gt;</pre></td>
<td>Enable/disable inverted HMOVE clock phase for ball.</td>
</tr><tr>
<td><pre>-dev.tia.delaypfbits &lt;1|0&gt;</pre></td>
<td>Enable/disable playfield bits delayed by one color clock (stray playfield pixels in Pesco).</td>
</tr><tr>
<td><pre>-dev.tia.delaypfcolor &lt;1|0&gt;</pre></td>
<td>Enable/disable playfield color delayed by one color clock (colored step borders in Quick Step!).</td>
</tr><tr>
<td><pre>-dev.tia.delaybkcolor &lt;1|0&gt;</pre></td>
<td>Enable/disable background color delayed by one color clock (stray pixels in Indy 500 menu hack).</td>
</tr><tr>
<td><pre>-dev.tia.delayplswap &lt;1|0&gt;</pre></td>
<td>Enable/disable player swap delayed by one color clock (He-Man title glitch).</td>
</tr><tr>
<td><pre>-dev.tia.delayblswap &lt;1|0&gt;</pre></td>
<td>Enable/disable ball swap delayed by one color clock.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;tv.jitter &lt;1|0&gt;</pre></td>
<td>Enable TV jitter/roll effect, when there are too many or too few scanlines
per frame.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;tv.jitter_recovery &lt;1 - 20&gt;</pre></td>
<td>When TV jitter/roll effect is enabled, determines how long to delay recovery
time (recovery spread over multiple frames).</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;colorloss &lt;1|0&gt;</pre></td>
<td>Enable/disable the PAL color-loss effect.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;debugcolors &lt;1|0&gt;</pre></td>
<td>Enable/disable the fixed debug colors.</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;timemachine &lt;1|0&gt;</pre></td>
<td>Enable/disable the Time Machine</td>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;tm.size &lt;20 - 1000&gt;</pre></td>
<td>Define the Time Machine buffer size.</td>
</tr><tr>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;tm.uncompressed &lt;0 - 1000&gt;</pre></td>
<td>Define the uncompressed Time Machine buffer size. Must be &lt;= Time Machine buffer size.</td>
</tr><tr>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;tm.interval &lt;1f|3f|10f|30f|</br> 1s|3s|10s&gt;</pre></td>
<td>Define the interval between two save states.</td>
</tr><tr>
</tr><tr>
<td><pre>-&lt;plr.|dev.&gt;tm.horizon &lt;3s|10s|30s|1m|3m|</br> 10m|30m|60m&gt;</pre></td>
<td>Define the horizon of the Time Machine.</td>
</tr>
</table>
</blockquote></br>
<h2><b><a name="Options">Changing Options</a></b></h2>
<blockquote>
<p>All settings can be changed within the integrated Options UI while Stella is
running (unless otherwise noted; some settings require an application restart).
The Options menu can be accessed from the ROM launcher by clicking the
<b>Options</b> button, or in-game by pressing the 'Tab' key.</p>
<p><b>Options Menu</b> dialog:<br><br>
<img src="graphics/options.png">
<br><br>
<p><b>Video & Audio Settings</b> dialog (Display):</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_video.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Renderer</td><td>Use specified rendering mode.</td><td>-video</td></tr>
<tr><td>Interpolation</td><td>Enable interpolation of the TIA image.</td><td>-tia.inter</td></tr>
<tr><td>Zoom</td><td>Adjust the zoom level of the TIA image</td><td>-tia.zoom</td></tr>
<tr><td>Fullscreen</td><td>Self-explanatory - Note that colors may slightly change.
This depends on the OS and renderer used.</td><td>-fullscreen</td></tr>
<tr><td>Stretch</td><td>In fullscreen mode, completely fill screen with the TIA image.</td><td>-tia.fs_stretch</td></tr>
<tr><td>Adapt display...</td><td>In fullscreen mode, adapt the display's refresh rate to the game's frame rate to minimize judder.
</br>Note: Not available for macOS.</td><td>-tia.fs_refresh</td></tr>
<tr><td>Overscan</td><td>In fullscreen mode, add overscan to the TIA image.</td><td>-tia.fs_overscan</td></tr>
<tr><td>Correct aspect ratio</td><td>Enable aspect ratio correct scaling.
</br>Note: Creates a cleaner looking TIA image when disabled (like z26 and old versions of Stella) vs. a correctly emulated aspect ratio when enabled.</td><td>-tia.correct_aspect</td></tr>
<tr><td>V-Size adjust</td><td>Adjust the height of the TIA image.</td><td>-tia.vsizeadjust</td></tr>
</table>
</td>
</tr>
</table>
<br>
<p><b>Video & Audio Settings</b> dialog (Palettes):</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_video_palettes.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Palette</td><td>Palette used for emulation mode</td><td>-palette</td></tr>
<tr><td>NTSC phase</td><td>Adjust phase shift of 'Custom' NTSC palette</td><td>-pal.phase_ntsc</td></tr>
<tr><td>PAL phase</td><td>Adjust phase shift of 'Custom' PAL palette</td><td>-pal.phase_pal</td></tr>
<tr><td>R</td><td>Adjust red scale and shift of 'Custom' palette</td><td>-pal.red_scale, -pal.red_shift</td></tr>
<tr><td>G</td><td>Adjust green scale and shift of 'Custom' palette</td><td>-pal.green_scale, -pal.green_shift</td></tr>
<tr><td>B</td><td>Adjust blue scale and shift of 'Custom' palette</td><td>-pal.blue_scale, -pal.blue_shift</td></tr>
<tr><td>Hue</td><td>Adjust hue of currently selected palette</td><td>-pal.hue</td></tr>
<tr><td>Saturation</td><td>Adjust saturation of currently selected palette</td><td>-pal.saturation</td></tr>
<tr><td>Contrast</td><td>Adjust contrast of currently selected palette</td><td>-pal.contrast</td></tr>
<tr><td>Brightness</td><td>Adjust brightness of currently selected palette</td><td>-pal.brightness</td></tr>
<tr><td>Gamma</td><td>Adjust gamma of currently selected palette</td><td>-pal.gamma</td></tr>
</table>
</td>
</tr>
</table>
<br>
<p><b>Video & Audio Settings</b> dialog (TV Effects):</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_video_tv.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>TV mode</td><td>Disable TV effects, or select TV preset</td><td>-tv.filter</td></tr>
<tr><td>Adjustable sliders</td><td>Set specific attribute in 'Custom' TV mode</td><td>-tv.sharpness, -tv.resolution, etc.</td></tr>
<tr><td>Phosphor for all ROMs</td><td>Enable phosphor mode for all ROMs</td><td>-tv.phosphor</td></tr>
<tr><td>Blend (phosphor)</td><td>Blend level to use in phosphor mode for all ROMs
(needs to be manually adjusted for your particular hardware)</td><td>-tv.phosblend</td></tr>
<tr><td>Scanline intensity</td><td>Sets scanline black-level intensity.</br>
Note: No scanlines in 1x mode snapshots.</td><td>-tv.scanlines</td></tr>
<tr><td>Clone RGB</td><td>Copy 'RGB' attributes to 'Custom' TV mode sliders</td><td>&nbsp;</td></tr>
<tr><td>Clone S-Video</td><td>Copy 'S-Video' attributes to 'Custom' TV mode sliders</td><td>&nbsp;</td></tr>
<tr><td>Clone Composite</td><td>Copy 'Composite' attributes to 'Custom' TV mode sliders</td><td>&nbsp;</td></tr>
<tr><td>Clone Bad adjust</td><td>Copy 'Bad Adjust' attributes to 'Custom' TV mode sliders</td><td>&nbsp;</td></tr>
<tr><td>Revert</td><td>Revert attribute sliders to saved 'Custom' TV mode settings</td><td>&nbsp;</td></tr>
</table>
</td>
</tr>
</table>
<br>
<p><b>Video & Audio Settings</b> dialog (Audio):</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_audio.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Enable audio</td><td>Self-explanatory</td><td>-audio.enabled</td></tr>
<tr><td>Volume</td><td>Self-explanatory</td><td>-audio.volume</td></tr>
<tr><td>Device</td><td>Use the specified audio device.</td><td>-audio.device</td></tr>
<tr><td>Mode</td><td>Select an audio preset or choose 'Custom' for manual configuration.</td><td>-audio.preset</td></tr>
<tr><td>Fragment size</td><td>The number of samples in a single fragment processed by the audio driver. Smaller values mean less latency, but may lead to dropouts (depending on OS and hardware).</td><td>-audio.fragment_size</td></tr>
<tr><td>Sample rate</td><td>
Output samples per second. Higher values reduce artifacts from resampling and decrease latency,
but may lead to dropouts (depending on OS and hardware).
</td><td>-audio.sample_rate</td></tr>
<tr><td>Resampling quality</td><td>
Chooses the algorithm used for resampling (= converting TIA output to the target sample rate).
'High' and 'ultra' use a high-quality Lanczos filter
but require slightly more CPU, while 'low' may lead to audible screeching artifacts in
some games (notably Quadrun).
</td><td>-audio.resampling_quality</td></tr>
<tr><td>Headroom</td><td>Number of frames to buffer before playback starts. Higher values increase latency, but reduce the potential for dropouts.</td><td>-audio.headroom</td></tr>
<tr><td>Buffer size</td><td>Maximum size of the audio buffer. Higher values increase maximum latency, but reduce the potential for dropouts.</td><td>-audio.buffer_size</td></tr>
<tr><td>Stereo for all ROMs</td><td>Enable stereo mode for all ROMs.</td><td>-audio.stereo</td></tr>
<tr><td>Pitfall II music pitch</td><td>Defines the pitch of Pitfall II music (which may vary between carts).</td><td>-audio.dpc_pitch</td></tr>
</table>
<p>
<strong>IMPORTANT:</strong> In order to maintain a stable stream of audio data, emulation speed must be
synchronized with the audio hardware. Buffering happens in multiple places (OS = fragment size, Stella =
headroom and buffer size) and improves the tolerance to speed fluctuations, but introduces latency which
manifests as a lag between audio and video.
</p><p>
Too aggressive settings for your combination of hardware and software (high sample rate,
low fragment size, low headroom, low buffer size) may lead to audio dropouts whose effect may range from
isolated popping artifacts to garbled audio. You can check the system log for related messages. If you
get recurring messages about audio overruns and underruns (isolates underruns / overruns are normal
and a consequence of host system activity), you might have to adjust your settings.
</p>
</td>
</tr>
</table>
<br>
<p><b>Emulation</b> dialog:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_emulation.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Emulation speed</td><td>Emulation speed</td><td>-speed</td></tr>
<tr><td>VSync</td><td>Enable vertical synced updates</td><td>-vsync</td></tr>
<tr><td>Turbo</td><td>Enable 'Turbo' mode for maximum emulation speed. This overwrites 'Emulation speed' setting and disables 'VSync'.</td><td>-turbo</td></tr>
<tr><td>Multi-threading</td><td>Enable multi-threaded rendering</td><td>-threads</td></tr>
<tr><td>Fast SuperCharger load</td><td>Skip progress loading bars for SuperCharger ROMs</td><td>-fastscbios</td></tr>
<tr><td>Show UI messages</td><td>Overlay UI messages onscreen</td><td>-uimessages</td></tr>
<tr><td>Confirm exiting...</td><td>Display a popup when emulation is exited</td><td>-confirmexit</td></tr>
<tr>
<td>When entering/exiting emulation:</td>
<td>
Automatically save no, current or all Time Machine states when exiting emulation.<br/>
The latter also loads all states when entering emulation. When this is enabled, you
can always continue your game session from where you exited it. Even including the
Time Machine buffer!
</td>
<td>-saveonexit</td>
</tr><tr>
<td>Automatically change...</td>
<td>
Automatically change to the next available save state slot after saving a ROM state file.
</td>
<td>-autoslot</td>
</tr>
</table>
</td>
</tr>
</table>
<br>
<p><b>Input Settings</b> dialog:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/eventmapping.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top"><br>This dialog is described in further detail in
<b>Advanced Configuration - <a href="#Remapping">Event Remapping</a></b>.</td>
</tr>
</table>
<br>
<p><b>User Interface Settings</b> dialog (2 tabs):</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_misc.png"><br><br></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Theme</td><td>Theme to use for UI elements (see examples)</td><td>-uipalette</td></tr>
<tr><td>Dialogs font</td><td>The font used in the dialogs</td><td>-dialogfont</td></tr>
<tr><td>HiDPI mode</td><td>Scale the UI by a factor of two when enabled</td><td>-hidpi</td></tr>
<tr><td>Dialogs position</td><td>Position of dialogs with Stella window</td><td>-dialogpos</td></tr>
<tr><td>Center windows</td><td>Attempt to center application windows, else position at last position</td><td>-center</td></tr>
<tr><td>List input delay</td><td>Maximum delay between keypresses in filelist-widgets before a search string resets. </td><td>-listdelay</td></tr>
<tr><td>Mouse wheel scroll</td><td>Number of lines a mouse scroll will move in list-widgets</td><td>-mwheel</td></tr>
<tr><td>Double-click speed</td><td>Speed of mouse double-clicks</td><td>-mdouble</td></tr>
<tr><td>Controller repeat delay</td><td>Delay before controller input repeats</td><td>-ctrldelay</td></tr>
<tr><td>Controller repeat rate</td><td>Rate of controller input repeats</td><td>-ctrlrate</td></tr>
</table>
</td>
</tr>
<tr>
<td><img src="graphics/options_misc_classic.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td><img src="graphics/options_misc_light.png"></td>
</tr>
<tr>
<td><img src="graphics/options_misc_dark.png"></td>
</tr>
</table>
<br>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_ui.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top"><br>This tab is described in further detail in
<b>Advanced Configuration - <a href="#ROMInfo">ROM Launcher</a></b>.</td>
</tr>
</table>
<br>
<a name="Snapshots"></a>
<p><b>Snapshot Settings</b> dialog:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/launcher_options_snapshots.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Save path</td><td>Specifies where to save snapshots</td><td>-snapsavedir</td></tr>
<!--<tr><td>Load path</td><td>Specifies where to load snapshots</td><td>-snaploaddir</td></tr> -->
<tr><td>Continuous snapshot interval</td><td>Interval (in seconds) between snapshots</td><td>-ssinterval</td></tr>
<tr><td>Use actual ROM name</td><td>Use the actual ROM filename instead of the internal database name</td><td>-snapname</td></tr>
<tr><td>Overwrite existing files</td><td>Whether to overwrite old snapshots</td><td>-sssingle</td></tr>
<tr><td>Create pixel-exact image (no zoom/post-processing)</td><td>Save snapshot using the exact pixels from the TIA image, without zoom or any post-processing effects</td><td>-ss1x</td></tr>
</table>
</td>
</tr>
</table>
<br>
<p><b>Developer Settings</b> dialog:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_developer.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top"><br>This tab is described in further detail in
<b>Advanced Configuration - <a href="#Debugger">Developer Options/Integrated Debugger</a></b>.</td>
</td>
</tr>
</table>
<br>
<p><b>Game Properties</b> dialog:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_gameinfo_emulation.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top"><br>This dialog allows you to change all ROM properties
as described in <b>Advanced Configuration - <a href="#Properties">Game Properties</a></b>.
</td>
</tr>
</table>
<br>
<p><b>Audit ROMs</b> dialog:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/romaudit.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top"><br>This dialog is described in further detail in
<b>Advanced Configuration - <a href="#ROMAudit">ROM Audit Mode</a></b>.</td>
</tr>
</table>
<br>
</blockquote></br>
<h2><b><a name="Remapping">Event Remapping/Input Devices</a></b></h2>
<blockquote>
<p>Almost every event in Stella can be remapped to another key on the keyboard or
to buttons on up to eight joysticks/gamepads (see <b>Getting Started -
<a href="#Keyboard">Keyboard Layout</a></b> for those events which can/cannot be
remapped).</p>
<p>Note that there are currently two separate event modes in Stella; emulation
mode and user-interface (UI) mode. Each mode has separate mappings, so (for example)
while in emulation mode, the left arrow could mean 'joystick 0 left', while in UI
mode it could mean 'move cursor left'. Emulation mode occurs whenever you're
actually playing a game. UI mode occurs whenever a user interface is present
(ROM launcher, debugger, settings menu, etc.). Because of these different modes,
there are two separate mapping areas.
<p>To remap an event:
<ol>
<li>Enter <b>Options Menu</b> and click the <b>Input Settings</b> button.</li>
<li>If you wish to remap emulation events, click the 'Emulation Events' tab. Here
you can also filter for the type of events.
Otherwise, click the 'UI Events' tab for user interface events.</li>
<li>Select event you want to remap and click the 'Map' button.</li>
<li>Now define the input:
<ul>
<li>Either press a key, a modifier key (Control, Shift...) or a modifier+key combination.</li>
<li>Or use a controller direction, a button or a button+controller direction combination.</li>
</ul>Then that key (combination) or controller action will be bound to the selected event.</br>
Notes:<ul>
<li>If nothing seems to happen, either Stella can't see the input device, or the
selected event doesn't support being remapped to the input device.</li>
<li>The same input can be used for multiple controller types (e.g. 'Right' for 'P0 Joystick Right' and 'Paddle 0 Turn Right').</li>
<li>If the same input is used again for the same controller type, the old mapping will be removed.</li>
<li>Events which are available in both event modes can be remapped individually.</li>
<li>Left and right modifiers are mapped separately when used alone.</li>
</ul></li>
</ol>
You can also:
<ul>
<li>Cancel a remap in progress by clicking 'Cancel'. <br/>Note: Pressing 'ESC' will map that key, <b>not</b> abort the mapping.</li>
<li>Erase all event's mappings by clicking 'Erase'.</li>
<li>Reset the event to its default mapping by clicking 'Reset'.</li>
<li>Reset <b>all</b> emulation or UI event mappings to default by clicking 'Defaults'.</li>
</ul>
<p>The following screenshots illustrate the event remapping process:<br><br>
<img src="graphics/eventmapping.png">
<img src="graphics/eventmapping_remap.png">
<p>Finally there is a 'Combo' button in the 'Emulation Events' tab, accessible
only when a Combo event has been selected from the list of events on the left.
Clicking 'Combo' will show a dialog similar to the following:</p>
<img src="graphics/eventmapping_combo.png">
<p>In this dialog, you can assign various events to the selected combo event.
Note that this simply assigns multiple events to the combo; you still need
to map the combo event itself to some action, as described in the 'remap an
event' section above.</p>
</p></br>
<p><b>Device and port</b> settings can be configured under the 'Devices & Ports' tab, shown below:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/eventmapping_devsports.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Joystick deadzone size</td><td>Deadzone area for axes on joysticks/gamepads</td><td>-joydeadzone</td></tr>
<tr><td>(Analog paddle) Sensitivity</td><td>Sensitivity of an analog paddle</td><td>-psense</td></tr>
<tr><td>Analog paddle) Dejitter averaging</td><td>Strength of paddle input averaging, suppresses mouse jitter</td><td>-dejitter.base</td></tr>
<tr><td>(Analog paddle) Dejitter reaction</td><td>Strength of paddle reaction to fast paddle movements, suppresses mouse jitter</td><td>-dejitter.diff</td></tr>
<tr><td>Digital paddle sensitivity</td><td>Sensitivity used when emulating a paddle using a digital device</td><td>-dsense</td></tr>
<tr><td>Autofire rate</td><td>Automatic trigger rate of the fire buttons in Hz</td><td>-autofirerate</td></tr>
<tr><td>Allow all 4 directions ...</td><td>Allow all 4 joystick directions to be pressed simultaneously</td><td>-joyallow4</td></tr>
<tr><td>Use modifier key combos</td><td>Enable using modifier keys in keyboard actions</td><td>-modcombo</td></tr>
<tr><td>Swap Stelladaptor ports</td><td>Swap the order of the detected Stelladaptors/2600-daptors (see <b>Advanced Configuration - <a href="#Adaptor">Stelladaptor/2600-daptor Support</a></b>)</td><td>-saport</td></tr>
<tr><td>Joystick database</td><td>Show all joysticks that Stella knows about, with the option to remove them</td><td>&nbsp;</td></tr>
<tr><td>Erase EEPROM</td><td>Erase the whole AtariVox/SaveKey flash memory</td><td>&nbsp;</td></tr>
<tr><td>AtariVox serial port</td><td>Described in further detail in <b>Advanced Configuration - <a href="#AtariVox">AtariVox/SaveKey Support</a></b> </td><td>-avoxport</td></tr>
</table>
</td>
</tr>
</table>
<p><b>Mouse</b> settings can be configured under the 'Mouse' tab, shown below:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/eventmapping_mouse.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Use mouse as ...</td><td>Allow the mouse to emulate various controllers</td><td>-usemouse</td></tr>
<tr><td>(Sensitivity) Paddle</td><td>Sensitivity used when emulating a paddle using a mouse</td><td>-msense</td></tr>
<tr><td>(Sensitivity) Trackball</td><td>Sensitivity used when emulating a trackball device using a mouse</td><td>-tsense</td></tr>
<tr><td>(Sensitivity) Driving controller</td><td>Sensitivity used when emulating a driving controller device using a mouse</td><td>-dcsense</td></tr>
<tr><td>Mouse cursor visibility</td><td>Show/hide cursor depending on current state</td><td>-cursor</td></tr>
<tr><td>Grab mouse ...</td><td>Keep mouse in window in emulation mode<br/>(only when used as controller)<br/>
Note: The sensitivity may greatly vary when the mouse is not grabbed.</td><td>-grabmouse</td></tr>
</table>
</td>
</tr>
</table>
</blockquote></br>
<h2><b><a name="ROMInfo">ROM Launcher</a></b></h2>
<blockquote>
<p>Several options are configurable in the ROM launcher. The size of the
launcher and fonts, as well as the 'ROM Info Viewer' can be changed in
<b>UI Settings - Launcher</b> dialog, as shown below:</p>
<img src="graphics/options_ui.png">
<p>Most of the options are self-explanatory, except for the 'ROM info
width', which is described below.</p>
<h3><b><a name="ROMInfoViewer">ROM Info Viewer</a></b></h3>
<p>Stella supports viewing snapshots and ROM properties of the currently
selected ROM in the ROM launcher. Support is automatic, as long as your
snapshot directory contains snapshots in the appropriate format. An
archive of updated snapshots will be available on the Stella webpage.
This archive may be updated periodically as new ROMs are found, and also
for each new release of Stella. Note that the snapshots can be any size
generated by Stella; they will be resized accordingly.</p>
The ROM Info Viewer's width can be defined between 0% (off) and 100%. The
value is relative to the launcher width. For too small or too large values,
Stella will automatically correct the width at runtime so that the ROM names
and the current ROM's information always have enough space.
<p>The following snapshots illustrate the various font sizes and rom info
widths:</p>
<p>ROM Info Viewer width at 40%, UI sized 800x480, small launcher font:</p>
<img src="graphics/rominfo_1x_small.png">
<p>ROM Info Viewer width at 32%, UI sized 1000x720, medium launcher font:</p>
<img src="graphics/rominfo_1x_large.png">
<p>ROM Info Viewer width at 50% , UI sized 1280x900, large launcher font:</p>
<img src="graphics/rominfo_2x_small.png">
<p>The text box in the upper right corner can be used to narrow down the
results in the ROM listing. When this box is empty, all files are shown
(subject to the restrictions from the filtering option, explained below).
Typing characters here will show only those files that match that
pattern. For example, typing 'Activision' will show only files that
contain the word 'Activision' in their name. This is very useful for
quickly finding a group of related ROMs. Note that the search is not
case sensitive, so you don't need to worry about capital or lower-case
letters.</p>
<h3><b><a name="ROMLauncherContextMenu">ROM Launcher Context Menu</a></b></h3>
<p>The ROM launcher also contains a context menu, selected by clicking the
right mouse button anywhere in the current window. This context menu
contains the following items:</p>
<p><ol>
<li><p><b>Power-on options</b>: Selecting this option shows a dialog whereby
ROM properties can be temporarily overridden, and joystick/console buttons can be
temporarily held down. Selecting options from this dialog will cause all ROMs launched
after that to use those properties you specify. Clicking <b>Defaults</b> will disable
its functionality, and use ROM properties as defined by the ROM itself. The dialog is as
follows (see <b>Advanced Configuration - <a href="#Properties">Game Properties</a></b>
for more information concerning ROM properties):</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/launcher_override.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>For more information,<br>see <a href="#CommandLine">Commandline</a></th></tr>
<tr><td>Bankswitch type</td><td>-bs</td></tr>
<tr><td>TV type</td><td>-tv</td></tr>
<tr><td>Left difficulty</td><td>-ld</td></tr>
<tr><td>Right difficulty</td><td>-rd</td></tr>
<tr><td>Startup mode</td><td>-debug</td></tr>
<tr><td>Left joy items</td><td>-holdjoy0</td></tr>
<tr><td>Right joy items</td><td>-holdjoy1</td></tr>
<tr><td>Console: Select</td><td>-holdselect</td></tr>
<tr><td>Console: Reset</td><td>-holdreset</td></tr>
</table>
<p></p>
</td>
</tr>
</table>
</li>
<br><li><b>Show only ROM files</b>: Selecting this reloads the current listing,
showing only files that have a valid ROM extension.</li>
<br><li><b>Show all files</b>: Selecting this reloads the current listing,
showing <i>all</i> files (with no restriction on file name).</li>
<br><li><b>Reload listing</b>: Selecting this performs a reload of the
current listing. It is an alternative to pressing the 'Control + r'
key combo.</li>
</ol></p>
</blockquote></br>
<h2><b><a name="ROMAudit">ROM Audit Mode</a></b></h2>
<blockquote>
<p>Stella has the ability to rename all your ROMs according to the name
specified in the properties database. This is useful if you've downloaded
ROMs in DOS 8.3 naming format, and wish the filenames to be more descriptive,
or the current filenames are too large to see in the launcher.</p>
<p>This feature is accessible from <b>Options =&gt; Audit ROMs</b>, and is only
available while in ROM launcher mode. The dialog box for this feature
is as follows:</p>
<img src="graphics/romaudit.png">
<p>Simply select the ROM path with the 'Audit path' button, and click the
'Audit' button. The ROMs will then be renamed according to their internal
properties. When the operation is complete, the number of ROMs that were
renamed (as well as ones that weren't) will be shown.</p>
<p>There are several items to take note of:</p>
<ul>
<li><b>THIS OPERATION CANNOT BE UNDONE</b>. I cannot stress this
enough; if you aren't completely sure you want to rename your ROMs,
don't use this function. There is no undo feature, and one won't be
added.</li>
<li>Only filenames that Stella considers to be valid ROMs will be
considered. Currently, this means files with extensions described in
"Supported File formats". Files which don't have these extensions will
be ignored.</li>
<li>If a valid ROM doesn't have a properties entry, it will be
ignored.</li>
</ul>
</blockquote></br>
<h2><b><a name="Adaptor">Stelladaptor/2600-daptor Support</a></b></h2>
<blockquote>
<p>Stella supports real Atari 2600 joysticks, paddles, driving controllers
and trackballs (CX22/CX80 'Trak-Ball', Atari and Amiga mouse) using the
<a href="http://www.grandideastudio.com/portfolio/stelladaptor-2600">Stelladaptor</a> and
<a href="http://2600-daptor.com">2600-daptor</a> devices.</p>
<p>Stella can use up to <b>two</b> adaptors; any extra ones are ignored.
Stelladaptor devices will be automatically detected and configured. The
actual controllers can be plugged/unplugged while the emulator is running,
although you will need to restart the game currently being emulated.</p>
<p>The detection and configuration is as follows:
<ul>
<li>The first device found will act as the <b>left game port</b>
on a real Atari. Depending on the device, Stella will detect it as
either the left joystick, paddles 0 & 1, the left driving controller,
left keypad, etc.</li>
<li>The second device found will act as the <b>right game port</b>
on a real Atari. Depending on the device, Stella will detect it as
either the right joystick, paddles 2 & 3, the right driving controller,
right keypad, etc.</li>
<li>Any other devices will be ignored.</li>
<li>The assignment ordering of Stelladaptor/2600-daptor to port can be redefined with
'saport' (see description in <a href="#CommandLine"><b>Using the Command Line</b></a>) and dynamically with the 'Control + 1' key
combo.</li>
</ul>
</blockquote></br>
<h2><b><a name="AtariVox">AtariVox/SaveKey Support</a></b></h2>
<blockquote>
<p>Stella supports a real AtariVox device for the speech/SpeakJet portion
of the controller. You will need a real AtariVox device
as well as some means of connecting it to your computer (some sort of
serial port/USB adaptor). There should be drivers for your serial convertor,
which allow your particular operating system to 'see' the device (configuring
this is outside the scope of this document). Once your operating system
properly detects the AtariVox, you will need to tell Stella which serial
port it is connected to. This is done by using the '-avoxport' command line
argument, or by setting it in the UI under the 'Devices & Ports' tab in
<b>Advanced Configuration - <a href="#Remapping">Input Devices</a></b>.</p>
<p>Note that you must use the entire name of the port as specified by
your operating system. For example, in Windows this would be COM1,
COM2, etc.; Linux and macOS tend to use names similar to '/dev/xxxxxx'.
For now, only Linux/UNIX, macOS, and Windows are supported.</p>
<p>Support for the EEPROM portion of the AtariVox and SaveKey is currently
emulated. That is, a file will be created on your computer simulating the
EEPROM; the actual EEPROM hardware itself will not be accessed or modified.
This is very useful in the testing stages of creating a new game, since
writing to a real EEPROM many times will eventually wear it out.</p>
<p>The location of EEPROM files will depend on the version of Stella, as follows:</p>
<p><table cellpadding="4" border="1">
<tr>
<td><b>Linux/Unix</b></td>
<td><i>$HOME/.config/stella/nvram/atarivox_eeprom.dat<br>
$HOME/.config/stella/nvram/savekey_eeprom.dat</i></td>
</tr>
<tr>
<td><b>Macintosh</b></td>
<td><i>$HOME/Library/Application Support/Stella/nvram/atarivox_eeprom.dat<br>
$HOME/Library/Application Support/Stella/nvram/savekey_eeprom.dat</i></td>
</tr>
<tr>
<td><b>Windows</b></td>
<td><i>%APPDATA%\Stella\nvram\atarivox_eeprom.dat<br>
%APPDATA%\Stella\nvram\savekey_eeprom.dat</i></td>
</td>
</tr>
<tr>
<td><b>If using 'basedir'<br>or 'baseinappdir'</b></td>
<td><i>_BASEDIR_/nvram/atarivox_eeprom.dat<br>
_BASEDIR_/nvram/savekey_eeprom.dat</i></td>
</tr>
</table>
<p>Note that these EEPROM files will be created when necessary, and
initialized as a real EEPROM would be (containing all $FF). The
files can be manually deleted, which is very useful in testing
cases where a ROM is accessing the EEPROM for the first time. You can also
reset the EEPROM to a clean state.</p>
</blockquote></br>
<h2><b><a name="Debugger">Developer Options/Integrated Debugger</a></b></h2>
<blockquote>
<p>Several developer related options can be configured in the 'Developer Settings' dialog.
Two sets ('Player settings', 'Developer settings') allow easy adjustment of all settings
for different use cases (playing or developing games) at once.</p>
<p><b>Developer Settings</b> dialog (Emulator)</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_developer_emulation.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Player/Developer settings</td><td>Selects the active settings set</td><td>-dev.settings</td></tr>
<tr><td>Console info overlay</td><td>Overlay console info on the TIA image during emulation.</td><td>-plr.stats<br/>-dev.stats</td></tr>
<tr><td>Detected settings info</td><td>Display detected settings when a ROM is loaded.</td><td>-plr.detectedinfo<br/>-dev.detectedinfo</td></tr>
<tr><td>Console</td><td>Select the console type, this affects Color/B&W/Pause key emulation and zero-page RAM initialization</td><td>-plr.console <br/>-dev.console</td></tr>
<tr><td>Random startup bank</td><td>Randomize the startup bank (only for selected bankswitch types)</td><td>-plr.bankrandom<br/>-dev.bankrandom</td></tr>
<tr><td>Randomize zero-page ...</td><td>When loading a ROM, randomize all RAM content instead of initializing with all zeroes (for 'Console' = 'Atari 2600' only)</td><td>-plr.ramrandom<br/>-dev.ramrandom</td></tr>
<tr><td>Randomize CPU</td><td>When loading a ROM, randomize the content of the specified CPU registers</td><td>-plr.cpurandom<br/>-dev.cpurandom</td></tr>
<tr><td>Drive unused TIA pins ...</td><td>Unused TIA pins are read random instead of the last databus values</td><td>-dev.tiadriven</td></tr>
<tr>
<td>Break on reads from ...</td>
<td>A read from a write port interrupts emulation and the debugger is entered.</td>
<td><span style="white-space:nowrap">-dev.rwportbreak</span></td>
</tr>
<tr>
<td>Break on writes to ...</td>
<td>A write to a read port interrupts emulation and the debugger is entered.</td>
<td><span style="white-space:nowrap">-dev.wrportbreak</span></td>
</tr>
<tr>
<td>Fatal ARM emulation ...</td>
<td>Thumb ARM emulation throws an exception and enters the debugger on fatal errors</td>
<td><span style="white-space:nowrap">-dev.thumb.trapfatal</span></td>
</tr>
<tr><td>Display AtariVox...</td><td>Display a message when the AtariVox/SaveKey EEPROM is read or written</td><td>-plr.eepromaccess<br/>-dev.eepromaccess</td></tr>
</table>
</td>
</tr>
</table>
<p><b>Developer Settings</b> dialog (TIA):</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_developer_tia.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Chip type</td><td>Type of emulated TIA chip. Allows testing for
TIA versions which exhibit timing problems in certain games. The
'Custom' option allows testing for glitch combinations.</td><td>-dev.tia.type</td></tr>
<tr><td>Inverted HMOVE clock...</td><td>Emulates the Kool-Aid Man
collision and Cosmic Ark stars glitches for the given objects.</td>
<td>-dev.tia.plinvphase</br>-dev.tia.msinvphase</br>-dev.tia.blinvphase</td></tr>
<tr><td>Delayed Playfield</td><td>Emulates playfield register changes delayed
by one color clock. This e.g. causes glitches in Pesco (stray playfield
pixel) and Quick Step! (colored step borders).</td>
<td>-dev.tia.delaypfbits</br>-dev.tia.delaypfcolor</td></tr>
<tr><td>Delayed Background</td><td>Emulates background color register changes delayed
by one color clock. This causes stray pixel in the Indy 500 menu hack.</td>
<td>-dev.tia.delaybkcolor</td></tr>
<tr><td>Delayed VDEL... swap for</td><td>Emulates a VDELP0/P1/BL swap
delayed by one color clock. This e.g cause glitches in the He-Man title
screen.</td>
<td>-dev.tia.delayplswap</br>-dev.tia.delayblswap</td></tr>
</table>
</td>
</tr>
</table>
<p><b>Developer Settings</b> dialog (Video):</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_developer_video.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Jitter/roll effect</td><td>Emulate screen roll with inconsistent scanline count</td><td>-plr.tv.jitter<br/>-dev.tv.jitter</td></tr>
<tr><td>(Jitter/roll) Recovery</td><td>Determines recovery time for screen rolling</td><td><span style="white-space:nowrap">-plr.tv.jitter_recovery<br/>-dev.tv.jitter_recovery</span></td></tr>
<tr><td>PAL color-loss</td><td>Use PAL color-loss effect</td><td>-plr.colorloss<br/>-dev.colorloss</td></tr>
<tr><td>Debug colors</td><td>Use fixed debug colors</td><td>-plr.debugcolors<br/>-dev.debugcolors</td></tr>
<tr>
<td>Player 0 <br/>Missile 0 <br/>Player 1 <br/>
Missile 1 <br/>Playfield <br/>Ball
</td>
<td>
Set color for specific object in 'Debug Colors' mode
(PF0, PF1 and PF2 have a slightly different luminance)<br/><br/>
Disabled in ROM launcher mode</td><td>-tia.dbgcolors
</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>Developer Settings</b> dialog (Time Machine)</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_developer_timemachine.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr>
<th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th>
</tr><tr>
<td>Time Machine</td>
<td>
When the Time Machine is enabled, Stella will automatically
buffer save states in the interval described below. The user
can then navigate back and forth within the recorded timeline.</br>
Note: This buffer is identical with the one described in
<a href="debugger.html#GlobalButtons"><b>Debugger - Global Buttons</b></a>.
It is independent from the save states manually created with F9.
</td>
<td>-plr.timemachine<br>-dev.timemachine</td>
</tr><tr>
<td>Buffer size</td>
<td>
Defines the Time Machine buffer size. The larger the buffer, the less
save states have to be compressed to reach the horizon.
</td>
<td>-plr.tm.size<br>-dev.tm.size</td>
</tr><tr>
<td>Uncompressed size (*)</td>
<td>
Defines the uncompressed Time Machine buffer size. States within this
area will not be compressed and keep their initial interval.</td>
<td><span style="white-space:nowrap">-plr.tm.uncompressed<br>-dev.tm.uncompressed</span></td>
</tr><tr>
<td>Interval</td>
<td>Defines the interval between two save states when they are created.</td>
<td>-plr.tm.interval<br>-dev.tm.interval</td>
</tr><tr>
<td>Horizon</td>
<td>
Defines the horizon of the Time Machine. A large horizon allows
going back further in time. To reach the horizon, save states
will be compressed (*). This means that more and more intermediate
states will be removed and the interval between save states
becomes larger the further they are back in time.<br>
(*) Compression only works if 'Uncompressed size' is smaller than
'Buffer size'.
</td>
<td>-plr.tm.horizon<br>-dev.tm.horizon</td>
</tr>
</table>
</td>
</tr>
</table>
<p><b>Developer Settings</b> dialog (Debugger)</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/options_developer_debugger.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>Brief description</th><th>For more information,<br>see <a href="#CommandLine">Command Line</a></th></tr>
<tr><td>Font size</td><td>Self-explanatory</td><td>-dbg.fontsize</td></tr>
<tr><td>Font style</td><td>Self-explanatory</td><td>-dbg.fontstyle</td></tr>
<tr><td>Debugger width/height</td><td>Self-explanatory</td><td>-dbg.res</td></tr>
<tr><td>Trap on 'ghost' reads</td><td>Defines whether the debugger should consider CPU 'ghost' reads for trap addresses.</td><td><span style="white-space:nowrap">-dbg.ghostreadstrap</span></td></tr>
</table>
</td>
</tr>
</table>
<br>
<p>Many more options are available for ROM developers, which are described in
different sections of this manual, as follows:</p>
<p><ul>
<li>Developer key-combo shortcuts, used to change TIA state dynamically
(ie, while the emulation is still running). See <b>Keyboard Layout -
<a href="#DeveloperKeys">Developer Keys in TIA mode</a></b> for more information.</li>
<li>Commandline options influencing emulation state. See <b>Using the Command Line -
<a href="#DeveloperCommandLine">Developer Commands</a></b> for more information.</li>
<li>Viewing TIA/console information overlaid on the TIA image. This option
can be enabled from the command line or using the Alt-L key combo,
and is extremely useful for viewing the current scanline count and associated
frames per second, bankswitch and display formats, etc. The following shows
an example of this information:
<p><img src="graphics/developer_stats.png"></p>
<p>The three lines of output describe the following:
<ol>
<li>Number of scanlines in current frame, associated framerate, and
resulting display format. Note that the framerate shown is the
<i>internal</i>, virtual framerate (it's calculated from the
number of scanlines). If the '*' character is present, it means
the display format was auto-detected as shown. For the given example,
the format was auto-detected as 'NTSC'.</li>
<li>Effective emulation speed displayed as frames per second and user
defined emulation speed displayed as percentage relative to normal speed.</li>
<li>Cartridge information. If the '*' character is present,
it means the bankswitch format was auto-detected as shown. The item
in round brackets indicates ROM size. For the given example,
the bankswitch type was auto-detected as 4K, and the file size was
4K (4096 bytes).</li>
</li>
</ol></p></li>
</ul></p>
<p>Finally, Stella contains an extensive, built-in debugger. Have a look at
<a href="debugger.html">this page</a> for integrated debugger documentation.</p>
</blockquote></br>
<h2><b><a name="Settings">Settings File</a></b></h2>
<blockquote>
<p>Stella will remember when you change a setting either at the command line
or while the emulation is running, and use the settings the next time
you start the emulator. The settings are saved in a text file which can
be edited outside of Stella. This file can contain your default options,
and eliminates the need to specify them on the command line. Any
options specified on the command line will override those in the settings file.</p>
<p>The syntax for the settings file is very straightforward. Any line starting with
a ';' character is considered a comment and is ignored. Other lines must be of
the form: <b>command = value</b>, where <i>command</i> is the same as that
specified on the command line (without the '-' character), and <i>value</i>
is dependent on the command.</p>
<p>For example, the following table illustrates how command line and settings entries
are similar:</p>
<table BORDER=2>
<tr>
<th>Command Line</th>
<th>Settings File</th>
</tr>
<tr>
<td>-video opengl</td>
<td>video = opengl</td>
</tr>
<tr>
<td>-volume 75</td>
<td>volume = 75</td>
</tr>
<tr>
<td>-center 1</td>
<td>center = 1 (or center = true)</td>
</tr>
</table>
<p>The settings file has a special name/location depending on which version of Stella
you use, which is not configurable:</p>
<p><table cellpadding="4" border="1">
<tr>
<td><b>Linux/Unix</b></td>
<td><i>$HOME/.config/stella/stellarc</i></td>
</tr>
<tr>
<td><b>Macintosh</b></td>
<td>Not applicable; settings are saved in <i>$HOME/Library/Preferences/Stella-emu.plist</i></td>
</tr>
<tr>
<td><b>Windows</b></td>
<td><i>%APPDATA%\Stella\stella.ini</i></td>
</tr>
<tr>
<td><b>If using 'basedir'<br>or 'baseinappdir'</b></td>
<td><i>_BASEDIR_/stellarc (or stella.ini)</i></td>
</tr>
</table>
</blockquote></br>
<h2><b><a name="Cheats">Cheatcode Manager</a></b></h2>
<blockquote>
<p>Stella contains support for Bob Colbert's Cheetah cheat codes, as
well as an extended Stella-specific type of cheat code that works on
bankswitched ROMs.</p>
<p>To add/remove/edit a cheat code, enter the 'Cheat Code' dialog:<br><br>
<img src="graphics/cheat.png">
<p>Currently, there are three types of cheatcodes available, all of which
must be entered in hexadecimal format:
<ul>
<li><p>Per-frame RAM cheats:<br>
Evaluated each frame, and apply to RAM only. Format as follows:
<pre>
4-digit code: c041
c0 = address
41 = data
</pre>
</li>
<li>Cheetah codes, which are explained in detail on
<a href="http://members.cox.net/rcolbert/">Bob Colbert's web page</a>,
along with a list of codes for various games. Cheetah codes
don't support bankswitched ROMs, so they only work for 2K or 4K ROMs.
Format as follows:
<pre>
6-digit (cheetah) code: aaaddc
aaa = address - $f000
dd = data
c = count - 1
</pre>
</li>
<li>Stella extended cheats are similar to Cheetah codes, except that
they can be 7 or 8 digits long, with the extra digits used for the
bank number:
<pre>
7-digit (stella) code: baaaddc
b = bank (0 to $f)
aaa = address - $f000
dd = data
c = count - 1
8-digit (stella) code: bbaaaddc
bb = bank (0 to $ff)
aaa = address - $f000
dd = data
c = count - 1
</pre>
</li>
</ul>
<p>There's also the concept of <i>one shot</i> codes. These codes work
exactly the same as above, except they aren't saved. They are evaluated
once and immediately discarded.
<p>Here are a few cheat codes we've found:</p>
<pre>
Pitfall (standard Cheetah codes):
5b0ea1 - infinite lives
723ea1 - infinite time
aa5??0 - set starting level, ?? = 01 to ff (d0 is kinda neat)
Battlezone (Stella extended codes):
1236ea1 - infinite lives
Ms Pac-Man (Stella extended codes):
108fea1 - infinite lives
</pre>
<p>The name of the cheat database file will depend on the version of Stella, as follows:</p>
<p><table cellpadding="4" border="1">
<tr>
<td><b>Linux/Unix</b></td>
<td><i>$HOME/.config/stella/stella.cht</i></td>
</tr>
<tr>
<td><b>Macintosh</b></td>
<td><i>$HOME/Library/Application Support/Stella/stella.cht</i></td>
</tr>
<tr>
<td><b>Windows</b></td>
<td><i>%APPDATA%\Stella\stella.cht</i></td>
</tr>
<tr>
<td><b>If using 'basedir'<br>or 'baseinappdir'</b></td>
<td><i>_BASEDIR_/stella.cht</i></td>
</tr>
</table>
<p>Stella will require a restart for changes to this file to take effect.</p>
</blockquote></br>
<h2><b><a name="Logs">Viewing the System Log</a></b></h2>
<blockquote>
<p>Stella maintains a log of its operations when the program first starts up, and
while it is running. In older releases, this information was only viewable from the
command line. However, the current release allows
you to see this information from within the UI. This can be selected from the main
Options menu, where it is labelled "System Logs". Clicking on the button will show
a window similar to the following:</p>
<table border="5" cellpadding="2" frame="box" rules="none">
<tr>
<td><img src="graphics/logs.png"></td>
<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>
<td valign="top">
<table border="1" cellpadding="4">
<tr><th>Item</th><th>For more information,<br>see <a href="#CommandLine">Commandline</a></th></tr>
<tr><td>Log level</td><td>-loglevel</td></tr>
<tr><td>Print to console</td><td>-logtoconsole</td></tr>
</table>
<p></p>
</td>
</tr>
</table>
<p>The log levels are self-explanatory (None, Basic, Verbose). The "Print to console"
option emulates the behaviour of older versions of Stella, whereby the logged output
is also shown on the command line from which Stella was launched (if it was launched
in that fashion). Finally, the current contents of the system log can be saved to your
home directory by clicking the "Save log to disk" button.</p>
</blockquote></br>
<h2><b><a name="Properties">Game Properties</a></b></h2>
<blockquote>
<p>Stella uses game properties to specify the "best" emulator settings for a
game. As of version 2.2 of Stella, a default database of properties are
built-in, but you may modify these through the use of a <b>stella.pro</b> file
or within the corresponding Game Properties dialogs.
This file will contain all properties modified by the user. So this
means that when you upgrade Stella, your personal properties settings are
preserved.</p>
<p>
<h2><b>Property File</b></h2>
<p>A property file consists of some number of blocks. Each block in the file
contains the properties for a single game. For example the general format of
a property file is:</p>
<p>
<pre>
; Comments
"Cart.MD5" "Value"
"Property" "Value"
""
; Comments
"Cart.MD5" "Value"
"Property" "Value"
""
. . .
; Comments
"Cart.MD5" "Value"
"Property" "Value"
""</pre>
<p>Every block in the property file must have a unique value for the
<i>Cart.MD5</i> property.</p>
<p>
<h2><b>Properties</b></h2>
<p>Each block in a property file consists of a set of properties for a single
game. Stella supports the properties described below:</p>
<h3><a name="Emulation"><b>Emulation Properties</b></a></h3>
<p>
<img src="graphics/options_gameinfo_emulation.png">
</p>
<table CELLSPACING="10">
<tr>
<td VALIGN="TOP"><a name="PropertiesCartType"><i>Cart.Type</i></a></td>
<td>Indicates the bank-switching type for the game.
The value of this property must be either <b>Auto</b> or one of the following
(for more information about bank-switching see Kevin Horton's <a href="http://kevtris.org/files/sizes.txt">2600 bankswitching
document</a> or the documentation in each cartridge's source code file) types. Types marked
as (&#185;) do currently have no reliable auto-detection, those marked as (&#178;)
are not fully supported in the debugger.
<table cellpadding="2" border="1">
<tr><th>&nbsp;Type&nbsp;</th><th>Description</th><th>File Extension<br>(to force type)</th></tr>
<tr><td>0840 </td><td>8K ECONObanking </td><td>.084, .0840</td></tr>
<tr><td>2IN1 &#185;</td><td>4-32K Multicart (2 games) </td><td>.2N1 </td></tr>
<tr><td>4IN1 &#185;</td><td>8-32K Multicart (4 games) </td><td>.4N1 </td></tr>
<tr><td>8IN1 &#185;</td><td>16-64K Multicart (8 games) </td><td>.8N1 </td></tr>
<tr><td>16IN1 &#185;</td><td>32-128K Multicart (16 games) </td><td>.16N, .16N1 </td></tr>
<tr><td>32IN1 &#185;</td><td>64-128K Multicart (32 games) </td><td>.32N, .32N1 </td></tr>
<tr><td>64IN1 &#185;</td><td>64/128K Multicart </td><td>.64N, .64N1 </td></tr>
<tr><td>128IN1 &#185;</td><td>256/512K Multicart </td><td>.128, .128N1 </td></tr>
<tr><td>2K </td><td>32-2048 bytes Atari </td><td>.2K </td></tr>
<tr><td>3E </td><td>512K Tigervision + 32K RAM</td><td>.3E </td></tr>
<tr><td>3EX </td><td>512K Tigervision + 256K RAM</td><td>.3EX </td></tr>
<tr><td>3E+ </td><td>3E+ (TJ modified 3E) </td><td>.3EP, .3E+ </td></tr>
<tr><td>3F </td><td>512K Tigervision </td><td>.3F </td></tr>
<tr><td>4A50 &#178;</td><td>64K 4A50 + RAM </td><td>.4A5, .4A50 </td></tr>
<tr><td>4K </td><td>4K Atari </td><td>.4K </td></tr>
<tr><td>4KSC </td><td>CPUWIZ 4K + RAM </td><td>.4KS, .4KSC </td></tr>
<tr><td>AR &#178;</td><td>Supercharger </td><td>.AR </td></tr>
<tr><td>BF </td><td>CPUWIZ 256K </td><td>.BF </td></tr>
<tr><td>BFSC </td><td>CPUWIZ 256K + RAM</td><td>.BFS, .BFSC </td></tr>
<tr><td>BUS </td><td>Experimental</td><td>.BUS </td></tr>
<tr><td>CDF </td><td>Chris, Darrell, Fred (includes CDFJ/CDFJ+)</td><td>.CDF </td></tr>
<tr><td>CM &#185;</td><td>Spectravideo CompuMate </td><td>.CM </td></tr>
<tr><td>CTY &#178;</td><td>CDW - Chetiry </td><td>.CTY </td></tr>
<tr><td>CV </td><td>CommaVid extra RAM </td><td>.CV </td></tr>
<tr><td>DF </td><td>CPUWIZ 128K </td><td>.DF </td></tr>
<tr><td>DFSC </td><td>CPUWIZ 128K + RAM</td><td>.DFS, .DFSC </td></tr>
<tr><td>DPC </td><td>Pitfall II </td><td>.DPC </td></tr>
<tr><td>DPC+</td><td>Enhanced DPC </td><td>.DPP, .DPC+ </td></tr>
<tr><td>E0 </td><td>8K Parker Bros </td><td>.E0 </td></tr>
<tr><td>E7 </td><td>16K M-network </td><td>.E7 </td></tr>
<tr><td>E78K </td><td>8K M-network </td><td>.E78, .E78K </td></tr>
<tr><td>EF </td><td>64K Homestar Runner </td><td>.EF </td></tr>
<tr><td>EFSC </td><td>64K Homestar Runner + RAM</td><td>.EFS, .EFSC </td></tr>
<tr><td>F0 </td><td>Dynacom Megaboy </td><td>.F0 </td></tr>
<tr><td>F4 </td><td>32K Atari </td><td>.F4 </td></tr>
<tr><td>F4SC </td><td>32K Atari + RAM </td><td>.F4S, .F4SC </td></tr>
<tr><td>F6 </td><td>16K Atari </td><td>.F6 </td></tr>
<tr><td>F6SC </td><td>16K Atari + RAM </td><td>.F6S, .F6SC </td></tr>
<tr><td>F8 </td><td>8K Atari </td><td>.F8 </td></tr>
<tr><td>F8SC </td><td>8K Atari + RAM </td><td>.F8S, .F8SC </td></tr>
<tr><td>FA </td><td>CBS RAM Plus </td><td>.FA </td></tr>
<tr><td>FA2 </td><td>CBS RAM Plus 24/28K </td><td>.FA2 </td></tr>
<tr><td>FC </td><td>Amiga Power Play Aracde 16/32K </td><td>.FC </td></tr>
<tr><td>FE </td><td>8K Decathlon </td><td>.FE </td></tr>
<tr><td>MDM </td><td>Menu Driven Megacart </td><td>.MDM </td></tr>
<tr><td>SB </td><td>128-256K SUPERbanking </td><td>.SB </td></tr>
<tr><td>TVBOY</td><td>512K TV Boy (127 games)</td><td>.TVB, .TVBOY </td></tr>
<tr><td>UA </td><td>8K UA Ltd. </td><td>.UA </td></tr>
<tr><td>UASW </td><td>8K UA Ltd. (swapped banks)</td><td>.UASW </td></tr>
<tr><td>WD </td><td>Wickstead Design (Pink Panther) </td><td>.WD </td></tr>
<tr><td>WDSW </td><td>Wickstead Design (Pink Panther) (bad)</td><td>.WDSW </td></tr>
<tr><td>X07 &#185;</td><td>64K AtariAge </td><td>.X07 </td></tr>
</table></td>
</tr>
<tr>
<td VALIGN="TOP"><i>Cart.StartBank</i></td>
<td>Indicates which bank to use for reading the reset vector.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Display.Format</i></td>
<td>Indicates the television format the game was designed for. The value
must be <b>Auto</b> or one of the following. Types marked as (&#185;)
do currently have no reliable auto-detection. A format can be enforced
by using one of the following pattern in the filename.
<table cellpadding="2" border="1">
<tr><th>&nbsp;Format&nbsp;</th><th>Filename Pattern (to force format)</th></tr>
<tr><td>NTSC</td><td>NTSC, NTSC60, NTSC 60, NTSC-60</td></tr>
<tr><td>PAL</td><td>PAL, PAL50, PAL 50, PAL-50</td></tr>
<tr><td>SECAM &#185;</td><td>SECAM, SECAM50, SECAM 50, SECAM-50</td></tr>
<tr><td>NTSC50 &#185;</td><td>NTSC50, NTSC 50, NTSC-50</td></tr>
<tr><td>PAL60 &#185;</td><td>PAL60, PAL 60, PAL-60</td></tr>
<tr><td>SECAM60 &#185;</td><td>SECAM60, SECAM 60, SECAM-60</td></tr>
</table></td>
</tr>
<tr>
<td VALIGN="TOP"><i>Display.VCenter</i></td>
<td>Indicates the offset for the vertical center of the display.
The value must be <i>n</i> such that -20 &lt;= <i>n</i> &lt;= 20.
</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Display.Phosphor</i></td>
<td>Indicates whether the phosphor effect should be emulated or not.
The value must be <b>Yes</b> or <b>No</b>.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Display.PPBlend</i></td>
<td>Indicates the amount of blending which will occur while using the
phosphor effect. The value must be <i>n</i> such that 0 &lt;= <i>n</i>
&lt;= 100. The default value is whatever is specified for tv.phosblend.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Cart.Sound</i></td>
<td>Indicates if the game should use 1 or 2 channels for sound output.
All original Atari 2600 machines supported 1 channel only,
but some homebrew games have been written to take advantage of stereo
sound mods. The value must be <b>Mono</b> or <b>Stereo</b>.</td>
</tr>
</table>
</br>
<!--
<p><b>Note:</b> Items marked as '*' are deprecated, and will probably be
removed in a future release.</p>
-->
<h3><a name="Consoler"><b>Console Properties</b></a></h3>
<p>
<img src="graphics/options_gameinfo_console.png">
</p>
<table CELLSPACING="10">
<tr>
<td VALIGN="TOP"><i>Console.TVType</i></td>
<td>Indicates the default television setting for the
game. The value must be <b>Color</b> or <b>BW</b>.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Console.LeftDiff</i></td>
<td>Indicates the default difficulty setting for the left
player. The value must be <b>A</b> or <b>B</b>.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Console.RightDiff</i></td>
<td>Indicates the default difficulty setting for the
right player. The value must be <b>A</b> or <b>B</b>.</td>
</tr>
</table>
</br>
<h3><a name="Controller"><b>Controller Properties</b></a></h3>
<p>
<img src="graphics/options_gameinfo_controller.png">
</p>
<table CELLSPACING="10">
<tr>
<td VALIGN="TOP">
<i>Controller.Left</i><br>
<i>Controller.Right</i><br>
</td>
<td>Indicates what type of controller the left and right player
uses. The value must be either <b>Auto</b> or one of the following types. Types marked
as (&#185;) do not have auto-detection yet.
<table cellpadding="2" border="1">
<tr><th>&nbsp;Type&nbsp;</th><th>Description</th></tr>
<tr><td>Joystick</td><td>Atari's famous black joystick that was originally included with the system.</td></tr>
<tr><td>BoosterGrip &#185</td><td>A controller add-in that plugs directly into the joystick port and provides a pass-through for the joystick. In doing so, it provides the two independent buttons.</td></tr>
<tr><td>Paddles </td><td>Standard paddle controllers for use with games such as Breakout and Warlords. One pair of controller per connector (allows for 4-player Warlords).</td></tr>
<tr><td>Paddles_IAxis &#185</td><td>Same as Paddles, except the axes are inverted.</td></tr>
<tr><td>Paddles_IAxDr &#185</td><td>Same as Paddles, except both the axes and direction of movement are inverted.</td></tr>
<tr><td>Driving &#185 </td><td>Looks like a paddle, but allows 360<36> movement. Only one unit per connector, unlike paddles which were sold in pairs.</td></tr>
<tr><td>Keyboard</td><td>Also known as the Star Raiders controller, functionally identical to the Kid's Controller and Keyboard Controller. Game included an overlay with commands, for use with Star Raiders.</td></tr>
<tr><td>AmigaMouse</td><td>Commodore Amiga computer mouse.</td></tr>
<tr><td>AtariMouse</td><td>Atari ST computer mouse.</td></tr>
<tr><td>Trakball</td><td>Standard Atari 2600 CX22/CX80 'Trak-Ball' controller.</td></tr>
<tr><td><a href="http://atariage.com/store/index.php?l=product_list&c=98">AtariVox &#185</a></td><td>A SpeakJet based unlimited-vocabulary speech/sound synthesizer with 32K EEPROM.</td></tr>
<tr><td>SaveKey</td><td>A 32K EEPROM for saving high scores, etc. (the EEPROM portion of an AtariVox).</td></tr>
<tr><td>Genesis </td><td>Sega Genesis controller, which can be used similar to a BoosterGrip, giving an extra button.</td></tr>
<tr><td>CompuMate &#185</td><td>Spectravideo CompuMate (if either left or right is set, CompuMate is used for both).</td></tr>
<tr><td>Lightgun</td><td>Atari XG-1 compatible Light Gun</td></tr>
<tr><td>Mindlink &#185</td><td>Mindlink controller.</td></tr>
<tr><td>KidVid &#185</td><td>KidVid controller, limited support (8, 9 and 0 start the games).</td></tr>
<tr><td>QuadTari</td><td><a href="#Quadtari">QuadTari</a> controller, limited support (see below).</td></tr>
</table></td>
</tr>
<tr>
<td VALIGN="TOP"><i>Console.SwapPorts</i></td>
<td>Indicates that the left and right ports should be
swapped internally. This is used for ROMs like 'Raiders of the Lost Ark' where the
Player 0 joystick is plugged into the right joystick port.
The value must be <b>Yes</b> or <b>No</b>.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Controller.SwapPaddles</i></td>
<td>Indicates that the left and right paddles in
a particular port should be swapped. This is used for ROMs like
'Demons to Diamonds' where the default paddle is paddle 1, not
paddle 0. Other ROMs such as 'Tac-Scan' default to paddle 3,
which can be set using both 'Controller.SwapPaddles' and
'Console.SwapPorts'. The value must be <b>Yes</b> or <b>No</b>.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Controller.PaddlesXCenter</i></td>
<td>Defines the horizontal center of the paddles (range -10..30).</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Controller.PaddlesYCenter</i></td>
<td>Defines the vertical center of the paddles (range -10..30).</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Controller.MouseAxis</i></td>
<td>Indicates how the mouse should emulate virtual controllers.
In 'Auto' mode, the system decides how to best use the mouse. Otherwise,
XY indicates how to use the X/Y axis (ie, 02 is paddle0/paddle2).
Currently, the mouse X-axis and left button are tied together, as are the
Y-axis and right button. The value must be <b>Auto</b> or <b>XY</b>, as follows:
<table cellpadding="2" border="1">
<tr><th>&nbsp;Id&nbsp;</th><th>Controller</th></tr>
<tr><td>0 </td><td>Paddle 0</td></tr>
<tr><td>1 </td><td>Paddle 1</td></tr>
<tr><td>2 </td><td>Paddle 2</td></tr>
<tr><td>3 </td><td>Paddle 3</td></tr>
<tr><td>4 </td><td>Driving 0</td></tr>
<tr><td>5 </td><td>Driving 1</td></tr>
<tr><td>6 </td><td>MindLink 0</td></tr>
<tr><td>7 </td><td>MindLink 1</td></tr>
</table>
An <I>optional</I> second parameter (default of 100) indicates how much
of the paddle range the mouse should emulate.
</td>
</tr>
<!--
In the latter case, XY indicates
how to use the X/Y axis (ie, 02 is paddle0/paddle2).
-->
</table>
</br>
<h3><a name="Quadtari"><b>QuadTari Properties</b></h3></a>
<p>
<img src="graphics/options_gameinfo_quadtari.png">
</p>
<table CELLSPACING="10">
<tr>
<td VALIGN="TOP">
<i>Controller.Left1</i><br>
<i>Controller.Left2</i><br>
<i>Controller.Right1</i><br>
<i>Controller.Right2</i><br>
</td>
<td>Indicates which controllers are plugged into one of the four QuadTari ports.
The value must be one of the following types.
<table cellpadding="2" border="1">
<tr><th>&nbsp;Type&nbsp;</th><th>Description</th></tr>
<tr><td>Joystick</td><td>Atari's famous black joystick that was originally included with the system.</td></tr>
<tr><td>Paddles </td><td>Standard paddle controllers, only (up to 8) fire buttons supported for QuadTari.</td></tr>
<tr><td>Driving</td><td>Looks like a paddle, but allows 360<36> movement. Only one unit per connector, unlike paddles which were sold in pairs.</td></tr>
<tr><td><a href="http://atariage.com/store/index.php?l=product_list&c=98">AtariVox</a></td><td>A SpeakJet based unlimited-vocabulary speech/sound synthesizer with 32K EEPROM.</td></tr>
<tr><td>SaveKey</td><td>A 32K EEPROM for saving high scores, etc. (the EEPROM portion of an AtariVox).</td></tr>
</table></td>
</tr>
</table>
</br>
<h3><a name="Cartridge"><b>Cartridge Properties</b></h3></a>
<p>
<img src="graphics/options_gameinfo_cartridge.png">
</p>
<table CELLSPACING="10">
<tr>
<td VALIGN="TOP"><i>Cart.Name</i></td>
<td>Indicates the actual name of the game. When you save snapshots,
load/save state files, or use the <a href="#ROMAudit"><b>ROM Audit Mode</b></a> functionality,
this is the name that will be used for the respective file(s).</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Cart.MD5</i></td>
<td>Indicates the MD5 checksum of the ROM image as a
string of hexadecimal digits. Stella uses this property while
attempting to match a game with its block of properties. If the
value of the property matches the MD5 checksum of the ROM image then
Stella uses that block of properties for the game. You can use the
GNU md5sum program, which is included with most Linux distributions,
to calculate the MD5 checksum of a ROM image.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Cart.Manufacturer</i></td>
<td>Indicates the game's manufacturer.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Cart.ModelNo</i></td>
<td>Indicates the manufacturer's model number for the game.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Cart.Rarity</i></td>
<td>Indicates how rare a cartridge is, based on the scale described on AtariAge.</td>
</tr>
<tr>
<td VALIGN="TOP"><i>Cart.Note</i></td>
<td>Contains any special notes about playing the game.</td>
</tr>
</table>
<p>The buttons at the bottom of the dialogs work as follows:
<ul>
<li><b>Defaults</b>: Reset the properties to those built into Stella.</li>
<li><b>Save</b>: Save the properties for the <i>currently selected ROM only</i>
to a properties file in the users default save directory.</li>
<li><b>OK</b>: Merge/commit any changes into the ROM properties database, which
contains info on all ROMs.</li>
<li><b>Cancel</b>: Revert any changes in the dialog, and cancel the operation.</li>
</ul>
<p>The name of the properties file will depend on the version of Stella, as follows:</p>
<p><table cellpadding="4" border="1">
<tr>
<td><b>Linux/Unix</b></td>
<td><i>$HOME/.config/stella/stella.pro</i></td>
</tr>
<tr>
<td><b>Macintosh</b></td>
<td><i>$HOME/Library/Application Support/Stella/stella.pro</i></td>
</tr>
<tr>
<td><b>Windows</b></td>
<td><i>%APPDATA%\Stella\stella.pro</i></td>
</tr>
<tr>
<td><b>If using 'basedir'<br>or 'baseinappdir'</b></td>
<td><i>_BASEDIR_/stella.pro</i></td>
</tr>
</table>
<p>Note: For manual changes to the property files Stella will require a restart to take effect.</p>
</blockquote></br>
<h2><b><a name="Palette">Palette Support</a></b></h2>
<blockquote>
<p>An Atari 2600 palette consists of 128 colours, which are different
for the three major television standards (NTSC, PAL, SECAM).
Stella supports two built-in palettes and one user-defined palette for each format.
These are set using the '-palette' option, and are described as follows:</p>
<p><table cellpadding="4" border="1">
<tr>
<td><b>standard</b></td>
<td>The default palette from Stella 1.4 onwards.</td>
</tr>
<tr>
<td><b>z26</b></td>
<td>The palette from the z26 emulator.</td>
</tr>
<tr>
<td><b>user</b></td>
<td>An external palette file, supplied by the user.</td>
</tr>
<tr>
<td><b>custom</b></td>
<td>A palette generate from user-defined phase shift.</td>
</tr>
</table>
<p>A user-defined palette has certain restrictions, further described as follows:
<ul>
<li>The palette file must be at least 792 bytes long. Colours are stored
in 24-bit RGB, with the first byte for red, the second for green, the
third for blue, for a total of 3 bytes per colour.</li>
<li>The first 384 bytes of the file (128 * 3) will be used for the NTSC
palette. The next 384 bytes (128 * 3) will be for the PAL palette.
The next 24 bytes (8 * 3) will be for the SECAM palette, which
consists of eight distinct colours. Any extra data in the file
will be ignored.</li>
<li>The PAL colour-loss effect is calculated within Stella. You do not
need to specify those colours in the palette file.
</ul>
<p>The name of the palette file will depend on the version of Stella, as follows:</p>
<p><table cellpadding="4" border="1">
<tr>
<td><b>Linux/Unix</b></td>
<td><i>$HOME/.config/stella/stella.pal</i></td>
</tr>
<tr>
<td><b>Macintosh</b></td>
<td><i>%HOME/Library/Application Support/Stella/stella.pal</i></td>
</tr>
<tr>
<td><b>Windows</b></td>
<td><i>%APPDATA%\Stella\stella.pal</i></td>
</tr>
<tr>
<td><b>If using 'basedir'<br>or 'baseinappdir'</b></td>
<td><i>_BASEDIR_/stella.pal</i></td>
</tr>
</table>
<p>Note that to actually use the external palette, the palette file must
exist and be valid, <b>and</b> the palette option should be set to <i>user</i>
(in <b>Video Settings</b> dialog). The current ROM will have to be reloaded
for changes to this file to take effect.</p>
</blockquote>
<!-- ///////////////////////////////////////////////////////////////////////// -->
<br><br>
<p><h1>
<a name="Acknowledgments">Acknowledgments</a></h1>
<hr>
<p>Bradford W. Mott started developing Stella during the fall of 1995, and Stephen
Anthony has maintained the project since around 2004. Over the years, a number of people
from around the world have contributed to the project.
Some people have provided technical help while others have offered suggestions
and praise. The Stella Team is grateful for all the help and support it has
received over the years. A (likely incomplete) list of the people who have
played a part in bringing Stella to you is available on the main Stella
webpage <a href="https://stella-emu.github.io/credits.html">Credits List</a>.
If we've missed someone, please let us know.</p>
<!-- ///////////////////////////////////////////////////////////////////////// -->
<br><br>
<p><h1>
<a name="License">License and Disclaimer</a></h1>
<hr>
<p>
<H2>GNU GENERAL PUBLIC LICENSE</h2>
<P>
Version 2, June 1991
</P>
<PRE>
Copyright (C) 1989, 1991 Free Software Foundation, Inc.
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
</PRE>
<H2>Preamble</H2>
<P>
The licenses for most software are designed to take away your
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</UL>
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<!-- we use this doubled UL to get the sub-sections indented, -->
<!-- while making the bullets as unobvious as possible. -->
<UL>
<LI><STRONG>a)</STRONG>
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<P><STRONG>NO WARRANTY</STRONG></P>
<P>
<STRONG>11.</STRONG>
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