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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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!
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.
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!
Alexander Bilstein
February 1999
Stella is a freely distributed multi-platform Atari 2600 VCS emulator; originally developed for Linux by Bradford W. Mott. 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).
The following sections outline the basic system requirements for running Stella under various operating systems.
Note that for this version of Stella, you are not required to have a stella.pro file. ROM properties are built in, and defaults will be used whenever necessary.
The Linux version of Stella is designed to work on a Linux Workstation with the following:
The Mac version of Stella is designed to work on a Power Macintosh with the following:
The Windows version of Stella is designed to work on Windows 98/ME/2000/XP/Vista with the following:
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 clean in Linux/Unix and Windows (Win32/Win64), and is expected to be compatible with 64-bit OSX as well. The Stella team is interested in hearing about any problems you may encounter with diverse operating systems and CPU types.
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.
If you have a supported joystick and driver installed and SDL can access the device, you can play games using joysticks.
Currently, sound is supported using SDL. As long as SDL can detect your sound card, Stella will be able to produce sound.
dpkg -i stella-release-1_arch.deb
rpm -Uvh stella-release-1.arch.rpm
tar zxvf stella-release-src.tar.gz
./configure (--help for list of options)
make
make install
Stella allows you to play games using ROM images of cartridges and cassettes.
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.
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:
WARNING: It is illegal to use ROM images of games that you do not actually own since these games are still copyrighted.
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.
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.
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:
% cat survivl0.bin survivl6.bin survivl7.bin > survivl.binor to create it under DOS you would:
% copy /b survivl0.bin+survivl6.bin+survivl7.bin survivl.bin
Once you have the multi-load ROM image file, survivl.bin in this case, you can play the game using it.
Once Stella is installed and you have some ROM images you're ready to start playing.
Stella contains an integrated GUI for all ports. Commandline support is also available for those who want to use it.
If you start Stella and do not specify a ROM image, it will start in
'ROM Launcher' mode:
If this is your first time starting Stella, you'll probably want to set the locations for ROM files, snapshots, and other external paths. These items are accessible by clicking the Options => Config Files buttons. Many other options can be set here, but for now we'll concentrate on Config Files only:
Config Files dialog:
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If you include the '~' character at the beginning of a path, it will be expanded to your home directory. For Linux/UNIX, this corresponds to your $HOME directory, but for Windows it means your 'My Documents' folder.
Selecting a new path for an item is done by clicking the appropriate button(s) (in this case, 'Rom path' was selected), which will show a browser as follows:
The browser should be self-explanatory. The 'Go Up' button moves to the parent folder (if it exists), and the 'Base Dir' button moves to the base directory where, by default, all Stella-related files are stored. Click 'Choose' to select an item, or 'Cancel' to exit the browser.
Once you've changed your settings, 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/Cmd or Space key(s). If a game uses a more complex controller, see Section 7 - Keyboard Layout for more information.
Stella can also be used from the commandline (assuming your operating system has a commandline).
To run Stella from the commandline, use the following format:
stella [options ...] ROM_FILENAME
Options ('0' or 'false' indicates false, '1' or 'true' indicates true, others are self-explanatory):
Argument | Description |
---|---|
-video <soft|gl> |
Use SDL software or OpenGL rendering mode. |
-gl_lib <filename> |
OpenGL mode only. Specify the OpenGL library to use (only use this if you know what you're doing). For OSX, this should probably be left blank. |
-gl_filter <nearest|linear> |
OpenGL mode only. Use GL_NEAREST or GL_LINEAR filtering. GL_NEAREST results in a scaled, pixelated image, while GL_LINEAR introduces blurring. |
-gl_aspectn <number> |
OpenGL mode only. Specify the amount (as a percentage) to scale the TIA image width in NTSC and PAL mode. Since many video modes do not use square pixels, you can reduce width until the pixels appear square. Allowable values are 80 - 120; I find 85 - 90 gives the most authentic look for NTSC, and 105 - 110 for PAL. |
-gl_fsmax <1|0> |
OpenGL mode only. Stretch TIA image while in fullscreen mode. |
-gl_vsync <1|0> |
OpenGL mode only. Synchronize screen updates to the vertical blank period. This can result in smoother updates, and eliminate tearing. |
-gl_texrect <1|0> |
OpenGL mode only. Enable GL_TEXTURE_RECTANGLE extension. This causes problems for some people using ATI video cards. |
-tv_tex <off|normal|stag> |
OpenGL 2.0 mode only. Enable TV texturing. The GL_TEXTURE_RECTANGLE extension must be disabled for this to work correctly. |
-tv_bleed <off|low|medium|high> |
OpenGL 2.0 mode only. Enable TV colour bleed emulation. A fast video card with at least 128MB RAM is required to use 'high'. The GL_TEXTURE_RECTANGLE extension must be disabled for this to work correctly. |
-tv_noise <off|low|medium|high> |
OpenGL 2.0 mode only. Enable TV radio frequency noise emulation. A fast video card with at least 128MB RAM is required to use 'high'. The GL_TEXTURE_RECTANGLE extension must be disabled for this to work correctly. |
-tv_phos <1|0> |
OpenGL 2.0 mode only. Enable phosphor effect of TV image. This is in addition to the currently emulated software phosphor effect. The GL_TEXTURE_RECTANGLE extension must be disabled for this to work correctly. |
-tia_filter <filter> |
Use the specified filter while in TIA/emulation mode. Currently, this can be zoomZx, where Z={2..10}. |
-fullscreen <1|0> |
Play the game in fullscreen mode. |
-fullres <auto|WxH> |
Use the given resolution in fullscreen mode. If 'auto', let Stella decide which resolution to use. |
-center <1|0> |
Centers game window (if possible). |
-grabmouse <1|0> |
Keeps the mouse in the game window. |
-palette <standard|z26|user> |
Set the palette to either normal Stella, the one used in the z26 emulator, or a user-defined palette. |
-colorloss <1|0> |
Enable/disable the PAL color-loss effect. |
-timing <sleep|busy> |
Determines type of wait to perform between processing frames. Sleep will release the CPU as much as possible, and is the preferred method on laptops (and other low-powered devices) and when using GL VSync. Busy will emulate z26 busy-wait behaviour, and use all possible CPU time, but may eliminate graphical 'tearing' in software mode. |
-framerate <number> |
Display the given number of frames per second. Normally, Stella will determine framerate based on number of scanlines. Setting this to 0 automatically enables auto-frame calculation (ie, framerate based on scanlines). |
-sound <1|0> |
Enable or disable sound generation. |
-fragsize <number> |
Specify the sound fragment size to use. Linux/Mac seems to work with 512, Windows may need 2048 (but newer versions work with 512 as well). |
-freq <number> |
Set sound sample output frequency (0 - 48000). Default is 31400. Do not change unless you experience sound issues. |
-tiafreq <number> |
Set sound sample generation frequency (0 - 48000). Default is 31400. Do not change unless you experience sound issues. |
-volume <number> |
Set the volume (0 - 100). |
-clipvol <1|0> |
Enable volume clipping (eliminates popping). Do not change unless you experience sound issues. |
-cheat <code> |
Use the specified cheatcode (see Cheat section for description). |
-showinfo <1|0> |
Shows some game info on the commandline while Stella is running. |
-joydeadzone <number> |
Sets the joystick deadzone area for analog joysticks. Accepts a number from 0 - 29, and uses the formula 3200 + number * 1000. So the possible deadzone values range from 3200 to 32200. |
-joyallow4 <1|0> |
Allow all 4 directions on a joystick to be pressed simultaneously. Bumper Bash ignores this setting, and always allows all 4 directions. |
-pspeed <number> |
Speed for digital emulation of paddles (1-15). |
-sa1 <left|right> |
Stelladaptor 1 emulates specified joystick port. |
-sa2 <left|right> |
Stelladaptor 2 emulates specified joystick port. |
-autoslot <1|0> |
Automatically switch to the next available save state slot after saving a ROM state file. |
-audiofirst <1|0> |
Initialize the audio subsystem before video when emulating a ROM. This seems to be required when using ATI video cards in OpenGL mode in Windows. Since it doesn't hurt other systems, the default is 1. |
-fastscbios <1|0> |
Disable Supercharger BIOS progress loading bars. |
-ssdir <path> |
The directory to save snapshot files to. |
-sssingle <1|0> |
Generate single snapshot instead of many, overwriting any previous snapshots. |
-ss1x <1|0> |
Ignore any scaling applied to the TIA image, and save snapshot in unscaled (1x) mode. |
-rominfo <rom> |
Display detailed information about the given ROM, and then exit Stella. |
-listrominfo |
Prints relevant contents of the Stella ROM database, one ROM per line, and then exit Stella. This can be used for external frontends. |
-uselauncher <1|0> |
Use the built-in ROM launcher. If disabled, launching Stella will simply print a help message, and exiting a ROM will completely exit the program. |
-launcherres <WxH> |
Set the size of the ROM launcher. |
-launcherfont <small|medium|large> |
Set the size of the font in the ROM launcher. |
-launcherexts <allfiles|allroms|LIST> |
Specifies which files to show in the ROM launcher ('allfiles' is self-explanatory, 'allroms' is all files with valid rom extensions (currently: a26, bin, rom, gz, zip), 'LIST' is a ':' separated list of valid rom extensions. |
-romviewer <0|1|2> |
Hide ROM info viewer in ROM launcher mode (0), or use the given zoom level (1 or 2). |
-uipalette <1|2> |
Used the specified palette for UI elements. This isn't yet complete. |
-listdelay <delay> |
Set the amount of time to wait between treating successive keypresses as a single word in list widgets (value can range from 300-1000). |
-mwheel <lines> |
Set the number of lines a mousewheel will scroll in the UI. |
-romdir <dir> |
Set the directory where the ROM launcher will start. |
-statedir <dir> |
Set the directory in which to save state files. |
-cheatfile <file> |
Set the full pathname of the cheatfile database. |
-palettefile <file> |
Set the full pathname of the user-defined palette file. |
-propsfile <file> |
Set the full pathname of the ROM properties file. |
-eepromdir <dir> |
Set the directory in which to save EEPROM files. |
-avoxport <name> |
Set the name of the serial port where an AtariVox is connected. |
-help |
Prints a help message describing these options, and then exit Stella. |
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 not case sensitive.
Argument | Description |
---|---|
-debuggerres <WxH> |
Set the size of the debugger window. |
-break <address> |
Set a breakpoint at specified address. |
-debug |
Immediately jump to debugger mode when starting Stella. |
-holdreset |
Start the emulator with the Game Reset switch held down. |
-holdselect |
Start the emulator with the Game Select switch held down. |
-holdbutton0 |
Start the emulator with the left joystick button held down. |
-stats <1|0> |
Overlay console info on the TIA image during emulation. |
-tiafloat <1|0> |
Set unused TIA pins to be floating on a read/peek. |
-bs <type> |
Set "Cartridge.Type" property. See the Game Properties section for valid types. |
-type <type> |
Same as using -bs. |
-channels <Mono|Stereo> |
Set "Cartridge.Sound" property. |
-ld <A|B> |
Set "Console.LeftDifficulty" property. |
-rd <A|B> |
Set "Console.RightDifficulty" property. |
-tv <Color|BlackAndWhite> |
Set "Console.TelevisionType" property. |
-sp <Yes|No> |
Set "Console.SwapPorts" property. |
-lc <type> |
Set "Controller.Left" property. See the Game Properties section for valid types. |
-rc <type> |
Set "Controller.Right" property. See the Game Properties section for valid types. |
-bc <type> |
Sets both "Controller.Left" and "Controller.Right" properties. See the Game Properties section for valid types. |
-cp <Yes|No> |
Set "Controller.SwapPaddles" property. |
-format <format> |
Set "Display.Format" property. See the Game Properties section for valid formats. |
-ystart <number> |
Set "Display.YStart" property (0 - 64). |
-height <number> |
Set "Display.Height" property (210 - 256). |
-pp <Yes|No> |
Set "Display.Phosphor" property. |
-ppblend <number> |
Set "Display.PPBlend" property, used for phosphor effect (0-100). Default is 77. |
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 Section 7 - Keyboard Layout. However, another alternative is available. Pressing the '\' key toggles a command menu dialog as follows:
This dialog contains a set of buttons that represent the same functionality as the function keys. 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).
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 Options button, or in-game by pressing the 'Tab' key.
Options Menu dialog:
Video Settings dialog:
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Video Settings dialog (TV Effects):
|
Audio Settings dialog:
|
Input Settings dialog:
This dialog is described in further detail in Section 8 - Event Remapping. |
UI Settings dialog (3 tabs):
This tab is described in further detail in Section 9 - ROM Launcher. |
|
|
Audit ROMs dialog:
This dialog is described in further detail in Section 10 - ROM Audit Mode. |
Game Properties dialog:
This dialog allows you to change all ROM properties as described in Section 16 - Game Properties. |
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 Section 8 - Event Remapping). The tables below show the default settings.
Console Controls (can be remapped)
Function | Key (Standard) | Key (OSX) |
---|---|---|
Exit emulator | Control + q | Cmd + q |
Exit game mode/enter launcher mode | Escape | Escape |
Enter/exit options mode | Tab | Tab |
Enter/exit command mode | Backslash (\) | Backslash (\) |
Enter/exit debugger | Backquote (`) | Backquote (`) |
Select Game | F1 | F1 |
Reset Game | F2 | F2 |
Color TV | F3 | F3 |
Black/White TV | F4 | F4 |
Left Player Difficulty B | F5 | F5 |
Left Player Difficulty A | F6 | F6 |
Right Player Difficulty B | F7 | F7 |
Right Player Difficulty A | F8 | F8 |
Save state to current slot | F9 | F9 |
Change current state slot | F10 | F10 |
Load state from current slot | F11 | F11 |
Save PNG snapshot | F12 | F12 |
Pause/resume emulation | Pause | Pause |
Joystick / BoosterGrip Controller (can be remapped)
Left Joystick (Joy0) | Right Joystick (Joy1) | ||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Paddle Controller digital emulation (can be remapped independently of joystick controller)
Left Paddles | Right Paddles | ||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Driving Controller (cannot be remapped, always associated with joystick controller)
Left Driving | Right Driving | ||||||||||||||||
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Keypad Controller (can be remapped)
Left Keypad | Right Keypad | ||||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Developer Keys in TIA mode (cannot be remapped)
Function | Key (Standard) | Key (OSX) |
---|---|---|
Set "Display.YStart" to next larger value | Alt + PageUp | Shift-Cmd + PageUp |
Set "Display.YStart" to next smaller value | Alt + PageDown | Shift-Cmd + PageDown |
Set "Display.Height" to next larger value | Control + PageUp | Cmd + PageUp |
Set "Display.Height" to next smaller value | Control + PageDown | Cmd + PageDown |
Toggle frame stats (scanline count/fps/bs type/etc) | Alt + l | Shift-Cmd + l |
Toggle TIA Player0 object | Alt + z | Shift-Cmd + z |
Toggle TIA Player1 object | Alt + x | Shift-Cmd + x |
Toggle TIA Missile0 object | Alt + c | Shift-Cmd + c |
Toggle TIA Missile1 object | Alt + v | Shift-Cmd + v |
Toggle TIA Ball object | Alt + b | Shift-Cmd + b |
Toggle TIA Playfield object | Alt + n | Shift-Cmd + n |
Turn all TIA objects off | Alt + . | Shift-Cmd + . |
Turn all TIA objects on | Alt + / | Shift-Cmd + / |
Other Keys (cannot be remapped, except those marked with '*')
Function | Key (Standard) | Key (OSX) |
---|---|---|
Switch to next larger zoom level | Alt + = | Cmd + = |
Switch to next smaller zoom level | Alt + - | Cmd + - |
Toggle fullscreen/windowed mode | Alt + Enter | Cmd + Enter |
Decrease volume (*) | Alt + [ | Shift-Cmd + [ |
Increase volume (*) | Alt + ] | Shift-Cmd + ] |
Grab mouse (keep mouse in game window) | Control + g | Cmd + g |
Toggle display palette (NTSC/PAL/SECAM) | Control + f | Cmd + f |
Save current properties to a new properties file | Control + s | Cmd + s |
Set mouse to emulate paddle 0 | Control + 0 | Cmd + 0 |
Set mouse to emulate paddle 1 | Control + 1 | Cmd + 1 |
Set mouse to emulate paddle 2 | Control + 2 | Cmd + 2 |
Set mouse to emulate paddle 3 | Control + 3 | Cmd + 3 |
Reload current ROM (singlecart ROM, TIA mode) Load next game in ROM (multicart ROM, TIA mode) |
Control + r | Cmd + r |
Reload ROM listing (ROM launcher mode) | Control + r | Cmd + r |
Emulate 'frying' effect (TIA mode) (*) | Backspace | Backspace |
Go to parent directory (UI mode) (*) | Backspace | Backspace |
Toggle 'phosphor' effect | Alt + p | Shift-Cmd + p |
Toggle palette | Control + p | Cmd + p |
Toggle PAL color-loss effect | Control + l | Cmd + l |
UI keys in Text Editing areas (cannot be remapped)
Key | Editor Function |
---|---|
Home | Move cursor to beginning of line |
End | Move cursor to end of line |
Delete | Remove character to right of cursor |
Backspace | Remove character to left of cursor |
Control-a | Same function as 'Home' |
Control-e | Same function as 'End' |
Control-d | Same function as 'Delete' |
Control-k | Remove all characters from cursor to end of line |
Control-u | Remove all characters from cursor to beginning of line |
Control-w | Remove entire word to left of cursor |
Control-Left | Move cursor to beginning of word to the left |
Control-Right | Move cursor to beginning of word to the right |
Control-c | Copy entire line to clipboard (not complete) |
Control-v | Paste clipboard contents (not complete) |
Almost every event in Stella can be remapped to another key on the keyboard or to buttons on up to eight joysticks/gamepads (see Section 7 - Keyboard Layout for those events which can/cannot be remapped).
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.
To remap an event:
The following screenshots illustrate the event remapping process:
Virtual devices can be configured under the 'Virtual Devs' tab, shown below:
|
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 UI Settings => Launcher dialog, as shown below:
Most of the options are self-explanatory, except for the 'ROM Info viewer', which is described below.
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.
Currently, there are several restrictions for this feature:
The following snapshots illustrate the various font sizes and rom info zoom levels:
ROM info viewer in 1x mode, UI sized 800x480, small launcher font:
ROM info viewer in 1x mode, UI sized 1000x760, medium launcher font:
ROM info viewer in 2x mode, UI sized 1400x900, large launcher font:
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 where 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.
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:
Override properties: Selecting this option shows a dialog whereby ROM properties can be temporarily overriden. Selecting options from this dialog will cause all ROMs launched after that to use those properties you specify. Clicking Default will disable its functionality, and use ROM properties as defined by the ROM itself. The dialog is as follows (See Section 16 - Game Properties for more information concerning ROM properties):
|
Filter listing: Selecting this option shows a dialog whereby one can filter the types of files shown in the listing. The dialog is as follows:
Currently, the choices are as follows:
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.
This feature is accessible from Options => Audit ROMs, and is only available while in ROM launcher mode. The dialog box for this feature is as follows:
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.
There are several items to take note of:
Stella supports real Atari 2600 joysticks, paddles and driving controllers using the Stelladaptor device.
Stella can use up to two Stelladaptors; any extra ones are ignored. Stelladaptor devices will be automatically detected and configured. Devices can be plugged/unplugged while the emulator is running, although you will need to restart the game currently being emulated.
The detection and configuration is as follows:
Stella supports a real AtariVox device for the speech/SpeakJet portion of the controller. You will need a real AtariVox device, located here, 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' commandline argument, or by setting it in the UI under the 'Virtual Devs' tab in 'Input Settings', as described in Section 8.
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 OSX tend to use names similar to '/dev/xxxxxx'. For now, only Linux/UNIX, OSX, and Win32 are supported.
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.
The location of the EEPROM files are configurable through the '-eepromdir' commandline argument and within the application itself (see Section 5 - Starting a Game). If the path for these files hasn't been set, the default location will depend on the version of Stella, as follows:
Linux/Unix | $HOME/.stella/atarivox_eeprom.dat $HOME/.stella/savekey_eeprom.dat |
Macintosh | $HOME/.stella/atarivox_eeprom.dat $HOME/.stella/savekey_eeprom.dat |
Windows | %APPDATA%\Stella\atarivox_eeprom.dat %APPDATA%\Stella\savekey_eeprom.dat OR _BASEDIR_\atarivox_eeprom.dat _BASEDIR_\savekey_eeprom.dat (if a file named 'basedir.txt' exists in the application directory containing the full pathname for _BASEDIR_) |
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.
Many options are available for ROM developers, which are described in different sections of this manual, as follows:
The two lines of output describe the following:
Finally, Stella contains an extensive, built-in debugger. Have a look at this page for integrated debugger documentation.
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.
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: command = value, where command is the same as that specified on the command line (without the '-' character), and value is dependent on the command.
For example, the following table illustrates how command line and settings entries are similar:
Command Line | Settings File |
---|---|
-video gl | video = gl |
-volume 75 | volume = 75 |
-showinfo 1 | showinfo = 1 (or showinfo = true) |
The settings file has a special name/location depending on which version of Stella you use, which is currently not configurable:
Linux/Unix | $HOME/.stella/stellarc |
Macintosh | Not applicable; settings are saved in $HOME/Library/Preferences/StellaOSX.plist |
Windows | %APPDATA%\Stella\stella.ini
OR _BASEDIR_\stella.ini (if a file named 'basedir.txt' exists in the application directory containing the full pathname for _BASEDIR_) |
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.
To add/remove/edit a cheat code, enter the 'Cheat Code' dialog:
Currently, there are three types of cheatcodes available, all of which must be entered in hexidecimal format:
Per-frame RAM cheats:
Evaluated each frame, and apply to RAM only. Format as follows:
4-digit code: c041 c0 = address 41 = data
6-digit (cheetah) code: aaaddc aaa = address - $f000 dd = data c = count - 1
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
There's also the concept of one shot codes. These codes work exactly the same as above, except they aren't saved. They are evaluated once and immediately discarded.
Here are a few cheat codes we've found:
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
The name of the cheat database file is configurable through the '-cheatfile' commandline argument and within the application itself (see Section 5 - Starting a Game). If the path for this file hasn't been set, the default filename will depend on the version of Stella, as follows:
Linux/Unix | $HOME/.stella/stella.cht |
Macintosh | $HOME/.stella/stella.cht |
Windows | %APPDATA%\Stella\stella.cht
OR _BASEDIR_\stella.cht (if a file named 'basedir.txt' exists in the application directory containing the full pathname for _BASEDIR_) |
Stella will require a restart for changes to this file to take effect.
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 stella.pro file. This per-user file will contain all properties modified by the user. So this means that when you upgrade Stella, your personal properties settings are preserved.
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:
; Comments "Cartridge.MD5" "Value" "Property" "Value" "" ; Comments "Cartridge.MD5" "Value" "Property" "Value" "" . . . ; Comments "Cartridge.MD5" "Value" "Property" "Value" ""
Every block in the property file must have a unique value for the Cartridge.MD5 property.
Each block in a property file consists of a set of properties for a single game. Stella supports the properties described below:
Cartridge.MD5: | 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. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cartridge.Manufacturer: | Indicates the game's manufacturer. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cartridge.ModelNo: | Indicates the manufacturer's model number for the game. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cartridge.Name: | Indicates the actual name of the game. When you save snapshots, load/save state files, or use the 'ROM Audit' functionality, this is the name that will be used for the respective file(s). | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cartridge.Note: | Contains any special notes about playing the game. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cartridge.Rarity: | Indicates how rare a cartridge is, based on the scale described on AtariAge. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cartridge.Sound: | 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. The value must be Mono or Stereo. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Cartridge.Type: | Indicates the bank-switching type for the game.
The value of this property must be either Auto-detect or one of the following
(for more information about bank-switching see Kevin Horton's 2600 bankswitching
document or the documentation in each cartridges source code file). Types marked
as (¹) do not currently have reliable auto-detection, those marked as (²)
are not fully supported in the debugger:
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Console.LeftDifficulty: | Indicates the default difficulty setting for the left player. The value must be A or B. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Console.RightDifficulty: | Indicates the default difficulty setting for the right player. The value must be A or B. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Console.TelevisionType: | Indicates the default television setting for the game. The value must be Color or BlankAndWhite. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Console.SwapPorts: | Indicates that the left and right ports should be swapped internally. This is used for ROMs like 'Raiders' where the Player 0 joystick is plugged into the right joystick port. The value must be Yes or No. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Controller.Left: | Indicates what type of controller the left player uses. The value must be BoosterGrip, Driving, Keyboard, Paddles, Trackball22, Trackball80, AmigaMouse or Joystick. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Controller.Right: | Indicates what type of controller the right player uses. The value must be BoosterGrip, Driving, Keyboard, Paddles, Trackball22, Trackball80, AmigaMouse, AtariVox, SaveKey or Joystick. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Controller.SwapPaddles: | 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 Yes or No. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Display.Format: | Indicates the television format the game was designed for. The value must be Auto-detect, NTSC, PAL, SECAM, NTSC50, PAL60 or SECAM60. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Display.YStart: | Indicates the scan-line to start displaying at. The value must be n such that 0 <= n <= 64. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Display.Height: | Indicates the number of scan-lines to display. The value must be n such that 210 <= n <= 256. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Display.Phosphor: | Indicates whether the phosphor effect should be emulated or not. The value must be Yes or No. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Display.PPBlend: | Indicates the amount of blending which will occur while using the phosphor effect. The value must be n such that 0 <= n <= 100. The default value is 77. |
The name of the properties file is configurable through the '-propsfile' commandline argument and within the application itself (see Section 5 - Starting a Game). If the path for this file hasn't been set, the default filename will depend on the version of Stella, as follows:
Linux/Unix | $HOME/.stella/stella.pro |
Macintosh | $HOME/.stella/stella.pro |
Windows | %APPDATA%\Stella\stella.pro
OR _BASEDIR_\stella.pro (if a file named 'basedir.txt' exists in the application directory containing the full pathname for _BASEDIR_) |
Stella will require a restart for changes to this file to take effect.
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:
standard | The default palette from Stella 1.4 onwards. |
z26 | The palette from the z26 emulator. |
user | An external palette file, supplied by the user. |
Support for a user-defined palette is a new feature for Stella 2.3, and is further described as follows:
The name of the palette file is configurable through the '-palettefile' commandline argument and within the application itself (see Section 5 - Starting a Game). If the path for this file hasn't been set, the default filename will depend on the version of Stella, as follows:
Linux/Unix | $HOME/.stella/stella.pal |
Macintosh | $HOME/.stella/stella.pal |
Windows | %APPDATA%\Stella\stella.pal
OR _BASEDIR_\stella.pal (if a file named 'basedir.txt' exists in the application directory containing the full pathname for _BASEDIR_) |
Note that to actually use the external palette, the palette file must exist and be valid, and the palette option should be set to user (in Video Settings dialog). The current ROM will have to be reloaded for changes to this file to take effect.
Bradford W. Mott started developing Stella during the fall of 1995 and since then 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. The following is an incomplete list of the people who have played a part in bringing Stella to you. If I've missed someone, please let me know.
Ant (http://aqfl.net) |
Provided much feedback and testing which eventually led to a fix for the infamouse ATI OpenGL 'red screen' issue |
Stephen Anthony (http://minbar.org) |
Ported Stella 1.1 to SDL. Added extra command line options to X11/SDL versions. Added INI file support, faster startup, snapshot support, and pause functionality to core. Converted Stella 1.1 manual to HTML. Ported codebase to SDL for Windows/MacOSX. Added OpenGL support and Stelladaptor support. Current maintainer for the Linux, OSX and Windows versions. |
David Aspell | Ported release 0.7 of Stella to Java |
Christopher Bennett | Helped discover a Superchanger emulation bug in release 1.0 of Stella |
Alexander Bilstein | Provided "A Brief History of the Atari 2600" for this manual |
Ian Bogost and the Georgia Tech Atari Team (CRT Simulation Project) |
Contributed code for the 'CRT simulation' OpenGL filters. The Winter 2009 team members are Edward Booth, Michael Cook, Justin Dobbs, William Rowland and Prince Yang. |
Dan Boris | Provided technical information on the Supercharger |
Piero Cavina | Allowed "Oystron" to be included in the Stella distribution |
Bob Colbert | Allowed "Okie Dokie" to be included in the Stella distribution |
Joe D'Andrea | Author of the IRIX port of Stella until release 1.2 |
Renato Ferreira | Provided code to support private colormaps under Unix |
Ron Fries | Author of the awesome TIA Sound library |
Aaron Giles | Author of the Power Macintosh version of Stella until release 1.1 |
Mark Grebe (http://www.atarimac.com) |
Author of the Macintosh OSX version of Stella starting with the 1.4 release until release 2.4. Helped with Stelladaptor support. |
Alex Herbert | Provided much information on AtariVox and SaveKey functionality |
Richard Hutchinson | Provided an AtariVox USB adaptor to help with AVox development |
Mark Hahn | Allowed "Elk Attack" to be included in the Stella distribution and provided help with the TIA HMOVE blank bug |
Kevin Horton | Author of the definitive Atari 2600 bank-switching document |
Thomas Jentzsch | Provided updated NTSC palette and many ideas |
Andrew Kator (http://www.katorlegaz.com) |
Provided PHP and CSS code for a major update to the Stella website |
Kostas Nakos | Author/maintainer of the WinCE version of Stella starting with the 2.0 release |
Erik Kovach | Author of the property file for release 0.7, 1.0, 1.1, and 1.2 of Stella |
Daniel Marks | Provided improved keyboard joystick support for Stella release 0.1 |
James Mcclain | Provided patches for the 1.2 release to get Stella to compile with GCC 3.0 |
David McEwen | Author of the Acorn version of Stella |
Jeff Miller | Author of the Windows version of Stella until release 1.2 |
Dan Mowczan | Provided a Supercharger to help with Stella's development |
Jack Nutting | Author of the OpenStep version of Stella |
John Payson | Provided EEPROM emulation code for AtariVox and SaveKey support |
Manuel Polik | Author of the Windows version of Stella starting with the 1.2 release |
Jim Pragit | Author of the "Game Menu" emulator game shell |
RomHunter (RomHunter ROMs) |
Provides an updated database of ROM information on a regular basis |
John Saeger | Participated in a helpful discussion on understanding the TIA's RESPx multi-sprite trick |
Chris Salomon | Provided information and code to help implement Supercharger support |
Glenn Saunders | Provided a Supercharger to help with Stella's development |
Jason Scott | Organizer of the property file archive for early versions of Stella; now he's helping with the web site |
Seagtgruff | Provided test ROMs which finally fixed all remaining issues with ADC/SBC opcode decimal mode emulation |
David Shaw | Provided make targets for the BSDI platform |
Raul Silva | Helped with design and graphics for an early version of the Stella web site |
Chris Snell | Maintained a mirror of the Stella FTP site |
Darrell Spice Jr. | Author of the OS/2 version of Stella |
John Stiles | Maintained the Macintosh version of Stella until release 1.2 |
Eckhard Stolberg | Provided a description of the TIA bug that produces the star field effect in Cosmic Ark, provided the PAL television palette, and participated in a helpful discussion on understanding the TIA's RESPx multi-sprite trick. Provided the Commavid, Megaboy, 4A50 and X07 support for Stella as well as some improved Supercharger BIOS code. |
Matthew Stroup | Author of the Amiga version of Stella |
Joel Sutton | Author of the FreeBSD version of Stella |
Greg Troutman | Allowed "This Planet Sucks" to be included in the Stella distribution |
Robert Tuccitto | Provided valuable bugtesting and feedback which finally helped in fixing a long-standing lockup which occurred after Stella has been running for 71 minutes. |
Curt Vendel | Provided schematics of the TIA which are being used to improve the TIA emulation. |
David Voswinkel | Maintainer of the PSP version of Stella starting with the 2.0 release |
Brian Watson | Helped with getting the illegal CPU instruction support working with Stella. Brian also submitted a number of other changes, such as debugger support, which have been finally integrated into the 2.0 release of Stella. Without a doubt, there would be no debugger support in Stella if not for the tireless work of Brian. |
Keith Wilkins | Maintained the DOS version of Stella until release 0.7 |
Jeff Wisnia | Provided technical data sheet for the 6532 RIOT chip |
Albert Yarusso (aka Al from AtariAge) | Provided helpful feedback for the OSX port, and generously donated an AtariVox device to help with development |
Alex Zaballa | Maintainer of the GP2X version of Stella starting with the 2.1 release |
Version 2, June 1991
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.
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7. If, as a consequence of a court judgment or allegation of patent infringement or for any other reason (not limited to patent issues), conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not distribute the Program at all. For example, if a patent license would not permit royalty-free redistribution of the Program by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution of the Program.
If any portion of this section is held invalid or unenforceable under any particular circumstance, the balance of the section is intended to apply and the section as a whole is intended to apply in other circumstances.
It is not the purpose of this section to induce you to infringe any patents or other property right claims or to contest validity of any such claims; this section has the sole purpose of protecting the integrity of the free software distribution system, which is implemented by public license practices. Many people have made generous contributions to the wide range of software distributed through that system in reliance on consistent application of that system; it is up to the author/donor to decide if he or she is willing to distribute software through any other system and a licensee cannot impose that choice.
This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License.
8. If the distribution and/or use of the Program is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Program under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License.
9. The Free Software Foundation may publish revised and/or new versions of the General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.
Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation.
10. If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally.
NO WARRANTY
11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.