NAME¶

stella - Atari 2600 emulator

SYNOPSIS¶

stella [ options] <ROM file>

DESCRIPTION¶

stella is a comprehensive emulator of the old Atari 2600 video-game console. It support most Atari 2600 games and many peripherals.

OPTIONS¶

stella accepts the following options:

-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).

-gl_filter <1|0>

OpenGL mode only. Use interpolation for the TIA image (results in blending/smoothing of the image).

-gl_aspectn <number>, -gl_aspectp <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_fsscale <1|0>

OpenGL mode only. Strech TIA image completely while in fullscreen mode (vs. an integral stretch which won't necessarily completely fill the screen).

-gl_vbo <1|0>

OpenGL mode only. Use the Vertex Buffer Object extension, if available. This is enabled by default.

-gl_vsync <1|0>

OpenGL mode only. Synchronize screen updates to the vertical blank period. This can result in smoother updates, and eliminate tearing.

-tv_filter <0-5>

OpenGL mode only. Blargg TV effets:

0

disabled

1

composite

2

S-video

3

RGB

4

bad adjust

5

custom

-tv_scanlines <0-100>

OpenGL mode only. Blargg TV effects scanline intensity, where 0 means completely off.

-tv_scaninter <1|0>

OpenGL mode only. Blargg TV effects scanline interpolation, resulting in blending/smoothing of the scanlines.

-tv_contrast <contrast>

OpenGL mode only. Blargg TV effects contrast (only available in custom mode, range -1.0 to 1.0).

-tv_brightness <brightness>

OpenGL mode only. Blargg TV effects brightness (only available in custom mode, range -1.0 to 1.0).

-tv_hue <hue>

OpenGL mode only. Blargg TV effects hue (only available in custom mode, range -1.0 to 1.0).

-tv_saturation <saturation>

OpenGL mode only. Blargg TV effects saturation (only available in custom mode, range -1.0 to 1.0).

-tv_gamma <gamma>

OpenGL mode only. Blargg TV effects gamma (only available in custom mode, range -1.0 to 1.0).

-tv_sharpness <sharpness>

OpenGL mode only. Blargg TV effects sharpness (only available in custom mode, range -1.0 to 1.0).

-tv_resolution <resolution>

OpenGL mode only. Blargg TV effects resolution (only available in custom mode, range -1.0 to 1.0).

-tv_artifacts <artifacts>

OpenGL mode only. Blargg TV effects artifacts (only available in custom mode, range -1.0 to 1.0).

-tv_fringing <fringing>

OpenGL mode only. Blargg TV effects fringing (only available in custom mode, range -1.0 to 1.0).

-tv_bleed <bleed>

OpenGL mode only. Blargg TV effects bleed (only available in custom mode, range -1.0 to 1.0).

-tia_filter <filter>

Use the specified filter while in TIA/emulation mode. Currently, this can be zoomZx, where Z is between 2 and 10 inclusive.

-fullscreen <1|0|-1>

Play the game in fullscreen mode (1), in a window (0), or completely disable fullscreen mode ( -1).

-fullres <auto|WxH>

Use the given resolution (WxH) in fullscreen mode. If auto, let Stella decide which resolution to use.

-center <1|0>

Centers game window (if possible).

-palette <standard|z26|user>

Sets 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.

-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).

-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.

-uimessages <1|0>

Enable or disablEnable or disable display of message in the UI. Note that messages indicating serious errors override this setting, and are always shown.

-sound <1|0>

Enable or disable sound generation.

-fragsize <number>

Specify the sound fragment size to use. Under Debian the recommended value is 512.

-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 the Cheat section in the provided documentation for a description of cheatcodes).

-loglevel <0|1|2>

Indicates 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.

-logtoconsole <1|0>

Indicates that logged output should be printed to the console/commandline as it's being collected. An internal log will still be kept, and the amount of logging is still controlled by loglevel.

-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.

-grabmouse <1|0>

Keeps the mouse in the game window in emulation mode.

-usemouse <1|0>

Use mouse as a controller as specified by ROM properties.

-dsense <number>

Sensitivity for emulation of paddles when using a digital device (joystick digital axis or button, keyboard key, etc.). number may range from 1 to 10, with larger numbers causing faster movement.

-msense <number>

Sensitivity for emulation of paddles when using a mouse. number may range from 1 to 15, with larger numbers causing faster movement.

-saport <lr|rl>

Determines 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.

-ctrlcombo <1|0>

Use control-x key combos. This is normally enabled, since the Quit command is tied to 'Control-q'. However, there are times when 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.

-autoslot <1|0>

Automatically switch to the next available save state slot after saving a ROM state file.

-stats <1|0>

Overlay console info on the TIA image during emulation.

-fastscbios <1|0>

Disable Supercharger BIOS progress loading bars.

-snapdir <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.

-ssinterval <number>

Set the interval in seconds between taking snapshots in continuous snapshot mode (currently, 1 - 10).

-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.

-exitlauncher <1|0>

Always exit to ROM launcher when exiting a ROM (normally, an exit to launcher only happens when started with the launcher).

-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>

Use 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.

-cfgdir <dir>

Set the directory in which to access Distella config files.

-avoxport <name>

Set the name of the serial port where an AtariVox is connected.

-maxres <WxH>

Useful for developers, this sets the maximum size of window that can be created, allowing to simulate testing on 'smaller' systems.

-help

Print 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.

-dis.resolvedata <never|always|auto>

Try to differentiate between code vs. data sections in the disassembler. See the Debugger section in the provided documentation for more information.

-dis.gfxformat <2|16>

Sets the base to use for displaying GFX sections in the disassembler.

-dis.showaddr <1|0>

Shows/hides opcode addresses in the disassembler.

-dis.relocate <1|0>

Relocate calls out of address range in the disassembler.

-debuggerres <WxH>

Set the size of the debugger window.

-break <address>

Set a breakpoint at a 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.

-tiadriven <1|0>

Set unused TIA pins to be randomly driven high or low on a read/peek.

-ramrandom <1|0>

On reset, either randomize all RAM content, or zero it out instead.

-bs <type>, -type <type>

Set "Cartridge.Type" property. See the Game Properties section in the provided documentation for valid types.

-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.TelevitionType" property.

-sp <Yes|No>

Set "Console.SwapPorts" property.

-lc <type>

Set "Controller.Left" property. See the Game Properties section in the provided documentation for valid types.

-rc <type>

Set "Controller.Right" property. See the Game Properties section in the provided documentation for valid types.

-bc <type>

Sets both "Controller.Left" and "Controller.Right" properties. See the Game Properties section in the provided documentation for valid types.

-cp <Yes|No>

Set "Controller.SwapPaddles" property. See the Game Properties section in the provided documentation for valid types.

-ma <Auto|XY>

Set "Controller.MouseAxis" property. See the Game Properties section in the provided documentation for valid types.

-format <format>

Set "Display.Format" property. See the Game Properties section in the provided documentation 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.

-thumb.trapfatal <true|false>

The default of true 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.

 

KEYBOARD CONTROLS¶

The Atari 2600 console controls and controllers are mapped to the computer's keyboard as shown in the following sections. However, most of these events can be remapped to other keys on your keyboard or buttons on your joystick.

Console controls (can be remapped)¶

Control + q

Exit emulator

Escape

Exit game mode/enter launcher mode

Tab

Enter/exit options mode

Backslash (\)

Enter/exit command mode

Backquote (`)

Enter/exit debugger

F1

Select Game

F2

Reset Game

F3

Color TV

F4

Black/White TV

F5

Left Player Difficulty A

F6

Left Player Difficulty B

F7

Right Player Difficulty A

F8

Right Player Difficulty B

F9

Save state to current slot

F10

Change current state slot

F11

Load state from current slot

F12

Save PNG snapshot

Pause

Pause/resume emulation

 

Joystick / BoosterGrip Controller (can be remapped)¶

Left joystick:

Up arrow

Joystick up

Down arrow

Joystick down

Left arrow

Joystick left

Right arrow

Joystick right

Space

Fire button

4

Trigger button

5

Booster button

Right joystick:

Y

Joystick up

H

Joystick down

G

Joystick left

J

Joystick right

F

Fire button

6

Trigger button

7

Booster button

 

Paddle Controller digital emulation (can be remapped independently of joystick controller)¶

By default the left paddles are mapped to the left joystick as follows:

Left

Paddle 0 decrease

Right

Paddle 0 increase

Fire

Paddle 0 fire

Up

Paddle 1 decrease

Down

Paddle 1 increase

Booster

Paddle 1 fire

The same mappings on the right joystick correspond to the right paddles (paddles 2 and 3 respectively).

Driving Controller (cannot be remapped, always associated with joystick controllers)¶

Each driving controller is mapped to the corresponding joystick, using the left, right and fire controls.

Sega Genesis Controller (cannot be remapped, always associated with joystick and booster-grip controllers)¶

Each pad is mapped to the correspondig joystick as follows:

Up

Up

Down

Down

Left

Left

Right

Right

Fire

Button 'B'

Booster

Button 'C'

 

Keypad Controller (can be remapped)¶

Left keypad (press the key on the left to emulate the key on the right):

1

1

2

2

3

3

Q

4

W

5

E

6

A

7

S

8

D

9

Z

.

X

0

C

#

 

Right keypad:

8

1

9

2

0 (the digit)

3

I

4

O (the letter)

5

P

6

K

7

L

8

;

9

,

.

.

0

/

#

 

CompuMate Controller (cannot be remapped)¶

0-9

0-9

A-Z

A-Z

Comma

Comma

Period

Period

Control

Func

Shift

Shift

; or Return/Enter

Enter

/ or Space

Space

Backspace

Func-Space

 

FILES¶

~/.stella/stellarc

Default options (command line options override these). Lines starting with ';' are considered comments and are ignored. Any other line 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 the value given to the setting.

~/.stella/atarivox_eeprom.dat

Default storage for the emulated EEPROM portion of an attached AtariVox device.

~/.stella/savekey_eeprom.dat

Default storage for the emulated EEPROM portion of an attached SaveKey device.

~/.stella/stella.cht

Default location of the cheat database file.

 

SEE ALSO¶

/usr/share/doc/stella/index.html, /usr/share/doc/stella/debugger.html.

AUTHORS¶

stella was written by Bradford W. Mott, Stephen Anthony and the Stella Team. This manual page was adapted from the provided documentation by Stephen Kitt <steve@sk2.org>, for the Debian GNU/Linux system (but may be used by others). It was last modified for stella version 3.4.1.