6.5.3 / 21-04-2021
Stella is a multi-platform Atari 2600 VCS emulator which was originally developed for Linux, but since its original release several people have joined the development team to port Stella to other operating systems such as AcornOS, AmigaOS, DOS, FreeBSD, IRIX, Linux, OS/2, MacOS, Unix, and Windows.
Windows: XP SP3+ (visual C++ Redistributable for Visual Studio 2017 is required)
Linux: Kernel 3.x+ and i386 / Ubuntu 20.04+
Mac: 10.7+ with 64-bit Intel processor
Most Recent Changes
Added context-sensitive help.
Improved support of multiple monitors with different resolutions.
Improved analog input reading (Paddles, Keyboards...).
Fixed QuadTari support for controller types other than Joysticks.
Fixed palette and TV effects saving for Retron77.
Fixed immediate disassembling when switching options in debugger.
February 25, 2021 - release 6.5.2
Fixed broken Driving Controller support for Stelladaptor/2600-daptor devices.
Fixed missing QuadTari option in UI.
Improved QuadTari timing.
Added CPU usage stats to ARM cart classes debug widgets.
January 24, 2021 - release 6.5.1
Fixed paddle button bug for jittering controllers.
Improve switching between joysticks and paddles on Retron77 port.
Improve memory usage on Retron77 port.
January 9, 2021 - release 6.5
Added high scores saving.
Improved text editing functionality (except PromptWidget):Enhanced selection and cut/copy/paste from keyboard.
Added undo and redo support.
Added mouse support (selection, cut/copy/paste).
All actions have keyboard shortcuts.
Various improvements to the ROM launcher:Added wildcard support to the dialog filter
Added option to search subdirectories
Added static tooltips to some UI items.
Added dynamic tooltips to most debugger items.
Added sound to Time Machine playback.
Added browser dialogs for user saved files.
Extended global hotkeys for input devices & ports settings.
Moved to using an SQLite database for storing user settings, properties and highscores. More work will follow in future releases.
Increased sample size for CDFJ+.
Fixed autofire bug for trackball controllers.
Fixed bug in TV autodetection in filenames; a filename containing 'PAL' inside a word would sometimes misdetect as a PAL ROM.
Fixed Stelladaptor/2600'daptor devices sometimes not being assigned correct default mappings.
Codebase now uses C++17 features, which means a minimum of gcc7 or clang5 for Linux/Mac, and Visual Studio 2019 for Windows.
November 2, 2020 - release 6.4
Added basic (entire and single line only) text cut/copy and paste.
Added color parameters to 'Custom' palette.
Some improvements to AtariVox-USB adaptor functionality:Made serial port used for an AtariVox-USB adaptor editable.
Autodetection of serial ports no longer messes up devices plugged into other serial ports.
Added CPU load stats to debugger. Related to this, added debugger pseudo-registers '_ftimreadcycles' and '_fwsynccycles' to show the number of cycles since the start of frame under certain circumstances (see manual for more details).
Fixed bug with aspect correction and fullscreen mode; snapshots from such a mode are now pixel-exact.
Fixed a bug that caused CDF ROMs to crash on the Retron77 and reduced ARM emulation performance for CDF ROMs on other platforms.
Fixed crash with missing or incorrectly sized SaveKey data file, and with certain functions not working (erase pages, erase entire EEPROM).
Fixed Atari mouse autodetection.
Fixed bug in ROM launcher, with last ROM selected not being remembered when exiting and re-entering a directory.
October 7, 2020 - release 6.3
Added adjustable autofire.
Added 'Dark' UI theme.
Extended global hotkeys for debug options.
Added option to playback a game using the Time Machine.
Allow taking snapshots from within the Time Machine dialog.
Basically, you are now able to put many files that Stella uses inside one ZIP file, and distribute just that file.Added the ability to access most files that Stella uses from within a ZIP file. This includes the following:Per-ROM properties file (so one can distribute a ROM and its associated properties).
Debugger symbol (.sym) and list (.lst) files, etc.
Several others, as we extend the support.
Extended AtariVox support to handle flow control, so that long phrases are no longer corrupted/cut off. This includes properly supporting the 2600-daptor II, which is flashable to an AVox-USB converter.
Added auto-detection of the serial port used for an AtariVox-USB adaptor.
Added QuadTari controller support.
Added option to select the audio device.
Added support for CDFJ+ bankswitching type.
Further enhanced UA bankswitching to support more Brazilian carts.
Added option to display detected settings info when a ROM is loaded.
Added another oddball TIA glitch option for delayed background color.
Added option to disable aspect ratio correct scaling.
Added debugger pseudo-registers '_timwrapread' and '_timwrapwrite', which are set when the RIOT timer is read/written on timer wraparound, respectively.
Bankswitching schemes BUS, DPC+ and CDFx now work when startup bank randomization is enabled (these schemes now ignore that setting).
Replaced "Re-disassemble" with "Disassemble @ current line" in debugger.
Fixed bug when taking fullscreen snapshots; the dimensions were sometimes cut off.
June 20, 2020 - release 6.2.1
Fixed Pitfall II ROM not working correctly.
Fixed crashes when using some combinations of bankswitching schemes on incorrect ROMs, or when using invalid ROM file sizes, etc.
Fixed RIOT timer behaviour on reading/writing at the wraparound cycle.
Fixed incorrectly setting D6 bit on TIA reads in some cases. Related to this, improve 'tiadriven' option to randomize only D5..D0 bits.
Fixed custom palette and TV effects adjustable slider rounding issue.
Fixed some bugs in 3E+ scheme when using non-standard ROM sizes.
Fixed crash in Audio & Video dialog when opened from debugger, and the debugger window sometimes being resized when using the Options dialog.
Make NTSC custom phase shift not affect Yellow anymore.
Fixed '1x' snapshot mode; TV effects are now disabled. This mode now generates a clean, pixel-exact image.
Fixed mappings sometimes not being saved in the Retron77 port.
A ROM properties file may now be placed next to the ROM (with the same name as the ROM, except ending in .pro), and Stella will automatically apply the properties to the ROM. [NOTE: this was present in 6.2, but was mistakenly left out of the changelog]
Added button to Game Info dialog to save properties of the currently loaded ROM to a separate properties file (in the default save directory). This is useful in conjunction with the previous item.
Allow changing custom palette and TV effects adjustables in 1% steps again.
Updated documentation for changes in ROM properties key names.
The codebase now compiles under gcc6 again. Future versions will require gcc7, though.
June 7, 2020 - release 6.2
Added interactive palette to Video & Audio settings.
Added 'Custom' palette, generated from user controlled phase shifts.
Added that adjustable audio & video settings are displayed as gauge bars.
Added four global hotkeys which allow selecting and changing numerous audio & video settings without having to remember the dedicated hotkeys.
Added 'Turbo' mode, runs the game as fast as the computer allows.
Added that paddle centering (per ROM) and sensitivity can be adjusted.
Added that mouse sensitivity for Driving controller can be adjusted.
Added paddle filtering in UI to avoid unwanted navigation events.
Added selectable dialog fonts.
Added separate positioning of launcher, emulator and debugger.
Added optional display to game refresh rate adaption in fullscreen mode.
Added option which lets default ROM path follow launcher navigation.
Added debugger 'saveaccess' function, which saves memory access counts to a CSV file.
Added displaying last write address in the debugger.
Added debugger pseudo-register '_scanend', which gives the number of scanlines at the end of the last frame.
Added detection of color and audio data in DiStella.
Restored 'cfg' directory for Distella config files.
Added TV Boy and 3EX bank switching types.
Removed unused CV+ and DASH bank switching types.
Added support for loading grayscale PNG images in the ROM launcher.
April 25, 2020 - release 6.1.2
Fixed bug with remapped events not being reloaded in certain cases.
Fixed bug in debugger for 3E scheme when displaying active RAM bank.
Fixed bug in "Dragon Defender" ROM being misconfigured for Mindlink controller.
April 4, 2020 - release 6.1.1
Fixed crash in 3E bankswitching scheme when writing to ROM addresses.
Fix snapshots on Retina HiDPI displays capturing only the top-left corner.
Fixed wrong color for BK (background) swatch in the debugger.
Fixed 'Right Diff' button in Command menu changing left difficulty instead.
Fixed compilation of libretro port on Debian Buster.
March 22, 2020 - release 6.1
IMPORTANT NOTES:Because of major event remapping changes, all remappings will be reset to defaults; if you had custom mappings, they will need to be re-entered again.
Because of major internal changes, all state files are now invalid.
Support for Windows XP has been discontinued as of this version. WinXP is now completely out of support from Microsoft, so we are doing the same.
Major improvements to display mode handling in NTSC vs. PAL. The window is now the same size for both modes, and scaling is applied to simulate the height of scanlines (in PAL mode, there are more scanlines and hence each is narrower). This more properly emulates how the display would look on a real TV.
Removed the 'Display_Height' property, changing it to 'Display_VCenter'. This new feature, along with the display mode changes above, almost completely eliminate having to manually tweak each ROM so that it will not have part of the image cut off.
Removed the 'Display_YStart' property and all automatic detection of ystart. It caused problems on some ROMs, and was not the way a real console would work anyway. Related to this, ROMs now load much faster.
Major improvements to event remapping:Allow mapping of modifier-key and button-direction combinations
Physical controllers can map the same action to different events on different virtual controllers
Many more events can be remapped
Events can be filtered by type in UI
Paths have been simplified:The following file/directory locations are no longer configurable (statedir, nvramdir, cheatfile, palettefile, propsfile); they are now all under the base directory
Removed cfgdir; Distella config files are now placed with their associated ROMs
Added 'basedir' commandline argument, which allows to change the base directory where almost all config-related items are stored; related to this, discontinued the 'basedir.txt' functionality
Added 'baseinappdir' commandline argument, which sets the base directory to the application folder (Windows only for now); this replaces the functionality of 'basedir.txt'
Added automatic controller detection.
Controllers can be changed during emulation (no ROM reload required anymore).
Added support for Light Gun controller.
Added limited KidVid support (8, 9 and 0 start the games).
Removed superfluous controller option 'PADDLES_IDIR'.
Added configurable paddle dejittering.
Key-repeat mode improved; entering Time Machine by holding down a key combo continues to send events (previously, you had to release and then press the combo again).
Certain buttons in the UI can now be activated repeatedly by holding down the mouse button (Time Machine, debugger step/trace/frame advance, etc.)
Added option to configure mouse double click speed.
Added option to configure controller input repeat speed.
Added high quality scaling.
Made scanlines better aligned to scaling.
Added 'HiDPI' mode, which scales the UI by 2x when enabled. This is meant for 4k and above monitors, but can actually be used at any lower resolution that is large enough to display the scaled UI.
Fixed TIA 'Center' option, Stella now remembers the last windowed position.
Added fractional (25% increments) TIA zooms.
Removed 'tia.fsfill' option, replacing it with 'tia.fs_stretch'. This new option allows to preserve TIA image aspect ratio in fullscreen mode, or stretch to fill the entire screen.
Added configurable 'Overscan' option for fullscreen modes.
Fullscreen TIA modes no longer assume that desktop taskbars, etc are present, hence they are scaled to the proper fullscreen size.
Added option to display dialogs in screen corners.
Added hotkey for sound on/off.
Enhanced 'Command' menu to display current state and more commands.
Added option to save and load all TimeMachine states at once.
Added option to automatically load/save states when entering/exiting emulation.
Added option to change pitch of Pitfall II music.
ROM Info Viewer size is not limited to fixed zoom steps anymore.
ROM Info Viewer can now display multiple lines per property and the bank switching type.
In file listings, you can now select directories by holding 'Shift' on the first character entered. Entering characters in lowercase still selects files, as before.
Fixed bug when starting ROMs via MacOS finder.
Added various developer options for oddball TIAs:stuffed player, missiles and ball move
delayed playfield bits and color
delayed players and ball VDEL swap
Disabled some developer options for 'Player settings'.
Writes to RAM read ports are ignored now.
Added Developer setting, which breaks on writes to read ports.
Improved breakpoints to now consider the banks.
Improved debugger's TIA display and zoom windows.
Improved hotkeys, now many emulation keys work in debugger too.
Fixed display of negative values in debugger; sometimes they were shown as positive.
Reworked ROM properties database, making it load faster in certain cases.
Updated internal ROM properties database to ROM-Hunter version 16 (thanks go to RomHunter for his tireless research in this area). Related to this, updated the snapshot collection.
Fixed 'Dancing Plate (Unknown) (PAL)' to use joystick.
Fixed cheatcode handling in 2K and 4K ROMs.
Fixed bug where ROMs smaller than 64 bytes were not recognized.
Fixed bug where frying one ROM was continued with the next ROM.
Fixed not working 7800 pause key.
Enhanced UA bankswitching to support certain Brazilian carts.
Fixed WD bankswitching.
Added FC bankswitching for Amiga's Power Play Arcade Video Game Album.
Added auto-detection of display format based on filename.
Auto-detection of bankswitch scheme by file extension now includes more human-readable formats (not restricted to DOS 3-char length). See the documentation for the new names.
Fixed bug in DPC+ scheme; 'fast fetch mode' was enabled at startup, when it should be disabled by default.
Some more work on DPC+ playfield 'jitter' effect for certain older DPC+ driver versions; more ROMs are now detected properly. Special thanks to SpiceWare for his research in this area.
Added proper Retron77 port.
Added proper libretro port, and fixed display for OpenGLES renderers.
PNG/ZIP image support is now conditionally compiled into Stella. All major ports (Linux/macOS/Windows) have it enabled by default.
SDL/GUI support is now conditionally compiled into Stella. All major ports (Linux/macOS/Windows) have it enabled by default. This is currently needed by the libretro port.
Updated included PNG library to latest stable version.
Updated UNIX configure script to work with the gcc version 10 and above.
October 11, 2019 - release 6.0.2
Updated properties database for Pink Panther ROM.
July 20, 2019
Updated Credits List for Stella-thon 2019. Thanks to all involved!
June 6, 2019 - release 6.0.1
Added support for CDFJ bankswitching type (Galaga, Wizard of War, etc).
Allow the DPC+ scheme to not enable playfield 'jitter' effect for certain older DPC+ driver versions; this allows 'Epic Adventure' ROM to finally work in Stella.
December 23, 2018 - release 6.0
Note: because of major TIA sound changes, the state file format has changed, and old state files will not work with this release.
New cycle exact audio core based on work by Chris Brenner (crispy); greatly improved audio emulation accuracy (i.e. E.T., Ms. Pacman).
Full rewrite of the audio subsystem; resample TIA output to target sample rate directly in Stella.
Added option to force stereo sound for all ROMs, or to use the setting on a per-ROM basis.
Threading: decouple emulation from frame rendering.
Main loop rewritten; emulating speed and timing is now much more faithful (i.e. speed in Pick'n'Pile).
Added preliminary support for 'CTY' bankswitching scheme and recently released 'Chetiry' ROMs. Special thanks to SpiceWare for adding music support to this scheme.
UI modernization (new widget look, dialog titles added, dialogs refactored).
The bankswitch scheme can now be forced by naming the ROM with a specific extension (ie: .f8s for F8SC, .fe for FE, etc). The supported extensions are the same as the ones from HarmonyCart and UnoCart.
Audio settings replaced with new 'audio.xxx' settings.
FPS setting replaced with speed setting for adjusting emulation speed.
Extra functionality for Time Machine dialog (start/stop recording; minor fixes).
When logging messages to the System Logger, condense similar messages that arrive in batches into fewer messages (including timestamps).
Fixes for collision corner cases (during HBlank).
Fixed excessive CPU usage while in UI modes (ROM launcher, debugger, etc).
The 'launcherexts' option has been replaced by a true/false option named 'launcherroms', which specifies to show only ROMs or all files in the ROM launcher.
Changes in 'Game Properties' dialog'Default' button now affects only current tab like in all other dialogs.
'Display' and 'Console' tab changes are now immediate.
Fixed bug when selecting 'Auto-detect' format for 50Hz ROMs
Fixed bug in autodetecting Genesis controllers.
Fixed bug with 'thumb.trapfatal' commandline argument; sometimes Stella would lock up when encountering a fatal error instead of entering the debugger and displaying a message.
Fixed bug in reading from settings file with entries that were empty; the parsing was failing. This affected the 'cpurandom' argument; when all options in it were turned off, they were all turned on again during the next program run.
Fixed bug with 'hold' events; they are now released a short time after starting a ROM.
When starting Stella for the first time, the first ROM selected will determine which path to use by default for subsequent runs.
Fixed emulator crash when starting SaveKey ROMs from commandline with SaveKey messages enabled.
Fixed missing TV format update in frame stats dialog when switching display type.
Fixed missing debug color update when switching display type.
'Fill to scanline' now works for scanlines above current scanline too.
The debugger 'uhex' command is now honoured in CDF and BUS schemes.
When switching screenmodes, the sound is now paused and later resumed. This fixes popping and cracking sounds apparent on some systems, notably macOS when toggling windowed/fullscreen mode.
State file format has been optimized to be smaller, and faster loading and saving. This affects both the files saved to your computer as well as Time Machine functionality.
The ROM name saved in a PNG tEXt chunk now honours the 'snapname' setting.
Improved snapshots when phosphor is enabled.
Updated PAL palette.
Added 'Cartridge.StartBank' ROM property, to force a ROM to use a specific bank for its reset vector.
Added Developer setting, which breaks on reads from write ports. It now detects such conditions in many more cases. This new way of detecting RWP errors obsoletes the old '_rwport' debugger command, which has now been removed.
Added recently released 'Arkyology' prototype ROM to the database.
Fixed 'Street Racer' and 'Video Olympics' ROMs to use paddles in both ports.
For UNIX systems: in the ROM launcher, when using symlinks use the symlink pathname instead of the underlying filesystem pathname.
The UNIX builds now use the system-installed PNG and ZLIB libraries by default.
The Macintosh builds are now named 'macOS' throughout the codebase to reflect the new naming from Apple.
For better compatibility, the Windows 32-bit version does not require SSE2 anymore.
Updated included PNG library to latest stable version.
June 10, 2018 - release 5.1.3
Fixed crash in OpenBSD when quitting the app, which can also be happening on other systems (no reports yet, but the problem is now fixed for good).
Fixed configure/build scripts to work natively under OpenBSD.
May 20, 2018 - release 5.1.2
Fixed bug with SaveKey autodetection; some ROMs were not correctly detecting that a virtual SaveKey device was plugged in. This notably fixes issues in "Super Cobra" and "Scramble" ROMs.
Make previously mentioned ROMs use the SaveKey device by default.
Fixed bug in UI navigation with joystick hat movement.
February 21, 2018 - release 5.1.1
Fixed bug in Stargunner ROM starting with a blank screen.
February 4, 2018 - release 5.1
Added "Time Machine" mode, which automatically creates save states in user-defined intervals. The user can navigate back and forth within these states inside the emulator and the debugger.
Huge improvements to the disassembly view in the debugger and disassembly files created:reformatting in debugger for better space utilization
much improved code and data detection
access tracking and indicators for TIA/IO/RAM adresses in disassembly
break vector is tracked (if used)
improved cycle count (page penalties, sums created in disassembly)
improved handling of instruction masking opcodes (e.g. BIT)
Fixed change tracking bug during rewind; changes were accumulated instead of being displayed only for the last rewind step.
Extended 'rewind' to take a second parameter which allows rewinding multiple states.
Added 'unwind' command, which undoes the latest rewind(s).
Added '<' (unwind) button to debugger.
Thumbulator support is not conditional any more.
Moved various developer related settings in new Developer Settings dialog. These settings now come in two groups (player/developer) and allow switching all settings at once.
Don't trap write accesses to the datastream pointers in CDF and BUS. This fixes -dev.thumb.trapfatal 1.
Complete rework of TV mode and ystart autodetection. The new implementation is more robust and reduces startup time.
Add two "grace lines" of black to the top of the frame when autodetecting ystart.
Fixed Genesis controller autodetect (Stay Frosty 2, Scramble, etc).
Fixed a bug in ystart autodetection that could cause screen jumps.
Fixed several bugs in holdselect, holdreset and holdjoyX commandline arguments; these now work as expected.
Fixed bug in TIA collision handling; it is now disabled in VBlank.
Improve TIA PF collision handling during hblank; this fixes a bug in Thrust ROM.
Fixed wrong display of HM values in debugger after 'HMCLR' has been executed.
Fixed bug with the debugger 'savedis' command in Windows; it wasn't actually saving the files at all. This has never been reported before, so I guess it shows how many people use that functionality.
The debugger 'savedis', 'saverom' and 'saveses' now save files in a default, user-visible directory (see the documentation for more information). In the case of 'saveses', the filename is now named based on the date and time of when the command was entered.
Fixed bug with saving snapshots in 1x mode; there was graphical corruption in some cases. Such snapshots also now include any TV effects / phosphor blending currently in use.
Fixed regular-sized snapshots when phosphor effect was enabled; sometimes the image was 'double-blended', resulting in a snapshot that was too dark.
Fixed crash when selecting 'CompuMate' as a controller type for a non- CompuMate ROM; this controller type can no longer be manually selected, and will be used automatically used for CompuMate ROMs.
Fixed cheat codes, so 7 digits codes are now accepted as described in the doc.
Fixed swapped ports being displayed wrong in System Logs and debugger.
Added options to erase the AtariVox/Savekey flash memory, either for all ROMs or only the current one. Also added a message (configurable) when the flash memory is accessed.
Access to the AtariVox/SaveKey can be signaled with a message.
Added new interface palette 'Light'.
Frame stats display made transparent. Also it now displays the real frame rate and if the developer settings group is enabled.
Improved tab auto-complete in debugger.
Added conditional traps and savestate creation to debugger.
Added 'Options...' button to debugger which gives access to the options menu during debugging.
Added debugger pseudo-register '_cyclesLo' and '_cyclesHi', which give the number of CPU cycles that have occurred since emulation started.
Added debugger pseudo-register '_fcycles', which gives the number of CPU cycles that have occurred since the frame started.
Added debugger pseudo-register '_icycles', which gives the number of CPU cycles of the last instruction.
Extended debugger 'dump' command to take a second argument, indicating the end of the range to dump data.
Improved change tracking; more values are tracked and change tracking now works in case of a break too.
Added widgets for trackball and SaveKey/AtariVox controllers.
Improved emulation of 'FE' bankswitch scheme (no user-visible changes, but internally the emulation is much more accurate compared to the real thing). Related to this, improved the debugger support for this scheme (you can now switch banks in the debugger view).
Added emulation of 7800 initial RAM values and Pause key.
Added ROM properties for 'Scramble' ROMs, and updated info for all "Champ Games" ROMs.
Added ROM properties for 'Zippy the Porcupine' ROMs, and updated info for all "Chris Spry (Sprybug)" ROMs.
Support UNIX style builds (configure / make) on OSX with both XCode / clang and g++.
Fixed error when building with uClibc-ng for ARM (thanks to Sergio Prado).
Updated included PNG library to latest stable version.
August 20, 2017 - release 5.0.2
Improved emulation of Trakball controller, eliminating bias in left/ right directions. Thanks to Thomas Jentzsch for the idea and code. Related to this, added 'tsense' commandline argument and associated UI item, to allow changing sensitivity of mouse trackball emulation.
Added preliminary support for multi-threading in the Blargg TV effects code. This is still a WIP; more improvements are coming. Related to this, further optimized the TIA rendering code. Also added 'threads' commandline argument and associated UI item to enable/disable multi-threading. Thanks to Thomas Jentzsch for the bulk of the work in this area.
Blargg TV effects now no longer cut off the right side of the image (by several pixels) in certain cases.
Updated CDF scheme to latest version from Spiceware. In addition, this scheme now supports versioning, so older and newer ROMs will continue to work.
Fixed an annoying bug in Linux, where Alt-Tab'ing out of a window and then back again would pass a 'Tab' key event to the app, which in most cases would navigate to the next UI element.
Fixed potential issue with state file saving and the debugger; under certain circumstances a rewind would give a different state than before (note that the state file format has changed because of this).
Fixed lockups when entering the debugger under certain circumstances.
The debugger 'listtraps' command now shows all traps set, not just the first one(s).
Reverted joystick changes for Decathlon ROMs from last release, as it was added by mistake.
August 1, 2017
The documentation for building Stella from source under Windows has changed.
July 23, 2017 - release 5.0.1
Fixed issues in keypad, Genesis and various other controllers that use INPTx registers; the emulation is now much more accurate in this area.
Various 'Bumper Bash' and 'Decathlon' ROMs are marked as always having all 4 directions on a joystick enabled, since they can't be played properly otherwise.
Added 'Hunchy II' from Chris Walton (cd-w) to ROM properties database.
Codebase now uses C++14 features.
July 16, 2017 - release 5.0
Note: because of major TIA/6502/RIOT changes, the state file format has changed, and old state files will not work with this release.
Stella has moved from Sourceforge to Github.
Completely new TIA core is now available, ported from 6502ts by Christian Speckner (DirtyHairy). This new core is extremely accurate, and matches real hardware in almost every test we've performed. New features include:Meltdown emulates correct
The lap number in Pole Positions displays correctly
Artifacts in the mountains on Snoopy and the Red baron are gone
Line artifacts in Title Match Pro Wrestling and Realsports Boxing are fixed
The spurious line at the left border of Video Chess now displays correctly
All 32 char text demos from AtariAge now work perfectly (Stella 4 shows artifacts on several of these)
Stella is now the only emulator to display the "Mega Bitmap Demo" (atext.bin) from AtariAge correctly
Improved starfield effect for missiles (still TODO for ball and players)
RSYNC emulation has improved, all testcases now match real hardware
Several other ROMs that have never worked in any emulator are now emulated correctly
RDY behavior with respect to write cycles is accurate
Optional YStart autodetect and more robust frame handling
NUSIZ during player draw matches hardware
RESMx during missile draw matches hardware
Paddle emulation is slightly more accurate. As a consequence, the "paddle feel" may be slightly different from Stella 4
Fixed debug colors can now be set for each graphical object, from a choice of 'red', 'orange', 'yellow', 'green', 'blue' and 'purple'. This is accessible through the new 'tia.dbgcolors' commandline argument and within the UI.
Implemented new phosphor emulation mode, which is much closer to real TV output. Related to this, added ability to change the default phosphor blend level in the UI and through the new 'tv.phosblend' commandline argument. Special thanks to Thomas Jentzsch for the idea and implementation.
TV phosphor effect can now be force-enabled for all ROMs, instead of manually setting ROM properties for each ROM. This is accessible in the UI and through the 'tv.phosphor' commandline argument, and defaults to being off (or enabled per-ROM).
PAL color-loss and Blargg TV effects can now be enabled at the same time. Previously, when Blargg effects were enabled, PAL color-loss couldn't be shown. Related to this, the Blargg effects now use much less memory and in some cases run faster than before.
Much improved RIOT timer emulation never before seen in any emulator. Special thanks to Christian Speckner (DirtyHairy) for the implementation, and alex_79 for finding documentation that finally describes in more detail how the M6532 chip actually works.
Added BUS (experimental) and CDF bankswitching schemes, and also ARM Timer 1 support; special thanks to SpiceWare for the code.
Fixed bug with SaveKey and AtariVox not properly closing their memory files before starting another instance of the same ROM, when the ROM was opened in the ROM launcher.
Various improvements to the debugger and command prompt:The 'cls' command now only clears the screen, not the history
The 'help' command now accepts other commands, and gives extra information about the command (ie, 'help breakif' prints extended information about the breakif command)
Added 'palette' command, which shows a color swatch of the currently active TIA palette
Added 'debugcolors' command, which shows a legend for 'fixed debug colors' mode
The previous trap'm' commands now work when setting TIA read addresses; previously they only worked for write addresses
The previous trap'm' commands are now renamed 'trap', 'trapread' and 'trapwrite'
The TIA tab now shows 'old' contents of player and ball registers
Various UI items are crossed out when disabled, to more clearly indicate their current state
Various UI items that previously required a double-click to toggle (pixel and bit widgets) now require only a single-click.
Command completion now works with internal functions and pseudo-ops (basically, anything starting with the '_' character)
System labels (aka, register names, etc) can now be typed in lower- case. Previously, these labels always had to be uppercase.
In general, input error checking is much more strictly enforced
Read-only UI items now have a different background color, to clearly indicate if an item can be modified.
Debugger '.lst' and '.sym' files are now searched based on the name of the ROM file, and not on the internal properties name.
Snapshots can now be saved by pressing the F12 key (the various other ways to save snapshots still exist).
Mouse grabbing is now enabled in windowed mode only when the ROM is using a virtual analog controller (paddles, trakball, etc).
Renamed various trakball-like controllers more accurately: AmigaMouse, AtariMouse (previously CX80) and Trakball (previously CX22). Related to this, reduced the resolution of the Trakball by half, to properly match real hardware.
The stack pointer (SP) is now initialized to $FD instead of $FF, to match research done in other 6502 projects.
Fixed bug in debugger tracing and displaying the partial TIA image; the first time entering the debugger and starting to trace, the image was blanked out (black) instead of being drawn in greyscale. Also, the image is now synchronized, instead of being two frames behind.
Fixed crash with zipped ROMs that are less than 4K in size; so far this bug has only ever occurred in Windows XP, but it's been there since Stella 4.1.
Fixed bug in 'Rom Audit' functionality; sometimes ROMs without a valid properties entry were being renamed as "Untitled.bin".
For the entire UI, removed colons and generally made the UI items easier to read.
When in 'ROM launcher mode', Stella now uses slightly less CPU time. More work is required in this area, though.
Added ROM properties for D.K. VCS homebrew ROM, thanks to Andreas Dietrich.
Added slight improvement for auto-detecting Superchip bankswitching; the new implementation now works for the NTSC 'Dig Dug' ROM. Special thanks for SpiceWare for the idea and modified implementation.
Fixed long-standing bug in 3-voice music in DPC+ bankswitching scheme; the music now sounds much more like the real thing.
For the Linux/UNIX port:The settings directory now uses the XDG Base Directory Specification. In most cases, this means that your files will now be stored in '~/.config/stella' instead of '~/.stella'. To keep your old settings, run the following commands from the terminal:
mv .stella .config/stella
You will probably need to edit '~/.config/stella/stellarc' and change some paths accordingly.
For the OSX port:Always use the built-in png and zlib libraries instead of the system versions.
The preferences file has changed from 'net.sourceforge.Stella.plist' to 'Stella-emu.plist'. To keep your old settings, run the following commands from the terminal:
mv net.sourceforge.Stella.plist Stella-emu.plist
Updated internal ROM properties database to ROM-Hunter version 13 (thanks go to RomHunter for his tireless research in this area). Related to this, updated the snapshot collection.
Updated included PNG and ZLIB libraries to latest stable version. Also, both libraries are now compiled into the app whenever one is selected. This fixes issues with a newer ZLIB not working with an older PNG, etc.
Updated build scripts for Visual Studio 2017 (Windows) and MacOS Sierra (latest version of Xcode), and make these the minimum supported versions for building Stella.
Updated UNIX configure script to work with the clang 5+ and gcc 7+ compiler versions, and fixed compile issues on AArch64 and ppc64le architectures.
November 21, 2016 - release 4.7.3
Added preliminary support for the 3E+ bankswitching scheme, developed by Thomas Jentzsch.
Fixed HMOVE positioning bug that occurred under certain circumstances. Thanks to Omegamatrix of AtariAge for the bug report and patch to fix the issue.
Added 'trapm', 'trapreadm', 'trapwritem' commands to debugger prompt. These are similar to the non-'m' versions, except that they also trap on all mirrors of the given address.
Fixed bug in debugger 'reset' command; it wasn't resetting the bankswitching, so after a reset the banks were in an undefined state.
Updated UNIX configure script to fix a bug where it fails in cross-compilation under certain circumstances. Thanks to Vlad Zakharov for providing a patch to fix this issue.
March 25, 2016 - release 4.7.2
Fixed bug when entering and exiting the debugger; sometimes the character corresponding to the '`' key would be output in the prompt area.
Updated DPC+ Thumb ARM emulation code to latest from David Welch. In particular, this fixes incorrect handling of the V flag when adding and subtracting, but also fixes compile-time warnings that I couldn't get rid of before.
Updated UNIX configure script to work with GCC 6.x compilers, and to remove references to obsolete compiler versions that can no longer be used to compile Stella.
February 13, 2016 - release 4.7.1
Improved TV 'jitter' emulation; the recovery time can now be spread over multiple frame, to simulate a real TV taking multiple frames to recover. Related to this, added new commandline argument 'tv.jitter_recovery' to set the recovery time. Finally, enabling the jitter effect and the recovery time are now accessible through the UI. Special thanks to SpiceWare of AtariAge for the initial idea and implementation.
Fixed bug with 'Medieval Mayhem' ROMs; the paddle range was set too low, and as a result the number of players couldn't be selected.
Fixed bug when using more than two input controllers with the same name; each controller after the second one was named the same as the second one. This caused the joystick mappings to be lost, since there was only information about two controllers being saved.
Indirectly fixed issues with Stelladaptor/2600-daptor devices and paddles having too large of a deadzone in Linux. Currently, this involves running an external application to set the deadzone, since SDL2 does not yet expose this information. The program is called 'evdev-joystick', and will be released separately from Stella.
Updated internal ROM properties database to ROM-Hunter version 11 (thanks go to RomHunter for his tireless research in this area). Related to this, updated the snapshot collection.
January 25, 2016 - release 4.7
Improved paddle emulation in several ways:Added ability to specify the maximum range of movement for paddles when using a mouse or digital device to emulate the paddle. This is useful since on a real console most paddle games use very little of the paddle range, and could result in moving the mouse onscreen with nothing appearing to happen (when in effect it was as if you turned a real paddle all the way to the end of the range). This eliminates issues in (for example) Kaboom, where there was a huge 'deadzone' when moving to the left. All applicable ROMS in the internal database have been updated.
The range for paddle emulation now takes an integer from 1 - 20, indicating how much to scale movement (ie, how fast the onscreen paddle will move when you move the mouse). The movement itself is now also smoother than before.
Fixed bug in 'Score mode' in TIA emulation; the TIA object colours were correct, but the associated priority was sometimes incorrect.
Fixed bug in ROM launcher; selecting 'Options -> Game Properties' after loading a ROM would always point to the last opened ROM, not to the one currently selected.
Fixed bug in storing ROM properties; in some cases, a copy of the ROM properties was being stored in the external file when it was exactly the same as the internal entry.
Added 'CV+' bankswitching scheme, developed by myself and LS_Dracon (of AtariAge). This scheme contains RAM like the CV scheme, and also switchable 2K ROM segments by writing to $3D.
Added more C++11 updates all over the codebase, and ran Stella through Coverity for the first time. I'm proud to say that Stella now has a 0.00 defect rate!
October 28, 2015
Stella release 4.6.7 for Linux, MacOS X and Windows is now available.
Fixed bug when using real paddles plugged into a Stelladaptor 2600-daptor device; the movement was very erratic.
Fixed small logic error in 'MDM' bankswitching scheme.
October 11, 2015
Stella release 4.6.6 for Linux, MacOS X and Windows is now available.
Added 'Alt/Cmd + j' shortcut key and 'tv.jitter' commandline argument to toggle the TV scanline jittering emulation added in the last release. Also, this jittering now defaults to off.
Fixed bug in 'MDM' bankswitch scheme; bankswitching wasn't being done under certain circumstances.
September 26, 2015
Stella release 4.6.5 for Linux, MacOS X and Windows is now available.
Added mappable events for toggling TV color/BW, left difficulty A/B and right difficulty A/B. This means that one key, joystick button, etc. can be used to toggle each event. Thanks to Buzbard of AtariAge for the suggestion.
Added ability to edit values in more widgets in the debugger. For now, this applies mainly to the various decimal and binary fields. More widgets will be made editable in future releases.
The TIA now emulates the jitter that occurs when scanline counts are not consistent frame-over-frame. Also, the DPC+ scheme now emulates jitter that can occur when using its Fractional Datafetchers if the DFxFRACINC registers are not re-initialized every frame. Special thanks to SpiceWare for this implementation.
Tweaked 'MDM' scheme autodetection to detect that the identification string can be in either bank 0 or bank 1.
Changed 'hidecursor' commandline argument (and associated UI item) to 'cursor'. The new argument allows to set mouse cursor visibility separately for both UI and emulation modes.
Fixed snapshot bug most noticeable in MacOSX, where taking a snapshot of a TIA image sometimes left parts of the UI onscreen (and in the resulting picture).
Fixed memory leak; the game console wasn't being closed after exiting a ROM.
For the Windows port: added an application icon for Stella in the Control Panel "Add/Remove Programs" list.
For the OSX port: Updated build scripts to be compatible with Xcode 7.
Updated included PNG library to latest stable version.
April 22, 2015
Stella release 4.6.1 for Linux, MacOS X and Windows is now available.
Fixed bug whereby text input could not be entered in certain widgets in the debugger.
Updated UNIX configure script to work with GCC 5.x compilers.
March 21, 2015
Stella release 4.6 for Linux, MacOS X and Windows is now available.
Finally fixed fullscreen rendering issues on some OpenGL implementations in Linux (mostly Intel-specific). Basically, the concept of 'dirty updates' has been removed; the window is now updated continuously. This may also fix issues some people were having with triple-buffering in Windows Direct3D, etc.
Fixed sound corruption that happened when running a ROM for the first time. This was most obvious under OSX, but occasionally happened on other systems too.
Reverted some minor C++11 features (std::regex and cbegin/cend iterators) in a few places, since otherwise GCC 4.9 is required to compile Stella, and it isn't available on many systems yet. These changes allow Stella to be built with GCC 4.8, which is present in the latest 'long term release' of Ubuntu.
Fixed error messages on state loading; sometimes multiple messages were being added together and displayed.
Fixed bug when running ROMs using AtariVox controllers; the app would crash upon exiting the ROM.
Snapshot functionality now works while the emulation is paused.
Certain textfields in the UI now have filtering enabled, preventing insertion of illegal characters. This will be extended throughout the code in future releases.
DataGridWidgets in the debugger now respond to keypad '+' and '-'.
Updated included PNG library to latest stable version.
January 1, 2015
Stella release 4.5 for Linux, MacOS X and Windows is now available.
The conversion to C++11 has begun :) From this point on, to build Stella you will need a C++11 compatible compiler (Visual Studio 2013, Clang 3.3, gcc 4.9, Xcode 6, etc). Eventually, this will bring more bug-free and (hopefully) faster code.
Fixed major bug with joysticks, where mapping was being lost on reset, the app would crash when plugging/unplugging certain sticks, etc.
Fixed major (but rare) crash that could occur when state files were zero'ed or corrupted.
Added dialog which shows the internal joystick database (all the joysticks that Stella knows about) and the ability to remove (currently unplugged) joysticks from this database.
Added preliminary support for 'WD' (Wickstead Design) bankswitching scheme, used for a previously unreleased prototype ROM.
Improved ZIP file handling, so that it now works as a normal filesystem does (it properly shows nested files and directories).
The debugger 'reset' command now does a complete system reset, instead of simply setting the PC to the reset vector address.
The 'listdelay' command now accepts a value of zero, indicating that list-skipping (jumping to a line in a list by keypress) is disabled.
The 'ctrlcombo' command now has a GUI item, allowing it to be changed from within the application.
Added 'Shift-Alt/Shift-Cmd s' keyboard shortcut, to enable continuous snapshot mode for each frame. This is really only useful if you save snapshots in 1x mode; using it in high-resolution mode is not recommended. Special thanks to SvOlli for the idea and code.
The minimum supported version for the OSX port is now OSX 10.7. Because of this, the 32-bit version is also discontinued, as 10.7 supports 64-bit Intel only apps.
Updated internal ROM properties database to ROM-Hunter version 10 (thanks go to RomHunter for his tireless research in this area). Related to this, updated the snapshot collection.
Updated included PNG library to latest stable version.
October 28, 2014
Stella release 4.2 for Linux, MacOS X and Windows is now available.
Text input from non-US keyboard layouts is now supported. Note that all text in Stella is still ASCII-only, but at least it can now be entered using a native layout.
Related to the text input changes, the debugger Alt-combo shortcuts have been changed; they now use the same key but with Control instead of Alt (Control-F for frame advance, etc).
Controllers are now detected dynamically by Stella. This means that you can plug/unplug joysticks/paddles/etc while Stella is running, and they will be added and removed automatically. Also fixed is a bug whereby sometimes custom joystick mappings weren't being saved.
The 'cpurandom' option is now broken down by register type, so you can selectively enable/disable randomization for each one. The default is to disable randomization for all registers.
Fixed 'MDM' scheme to trigger bankswitching on writes to hotspots (previously it only triggered on reads). Also, the scheme has been modified as originally designed by E. Blink; hotspots are now in the range $800-$BFF instead of $800-$FFF.
The OSX app-icon now includes 32x32 and 16x16 versions, so 'small' icons will be viewable in 'Finder', 'Get Info', etc.
The Linux port now uses an app-icon; this seems to be needed for some window managers.
September 14, 2014
Stella release 4.1.1 for Linux, MacOS X and Windows is now available.
Re-added 'uipalette' option due to popular demand (of at least one person :)).
Fixed bug in Windows port where pressing 'Alt' key combos resulted in an annoying system beep. Currently this is fixed by patching the SDL2 library and including a modified version with Stella.
September 1, 2014
Stella release 4.1 for Linux, MacOS X and Windows is now available.
Improved 'DASH' bankswitching scheme support; there is now a debugger tab for changing banks and viewing internal cart RAM, and autodetection is now implemented.
Added 'MDM' (Menu Driven Megacart) bankswitch scheme as described on AtariAge and originally developed by Edwin Blink.
Improved snapshot viewing in the ROM launcher; snapshots are now scaled to the available space, and can better accommodate sizes other than those generated by Stella itself.
Improved support on multi-monitor systems. Stella will now use the same monitor for fullscreen-windowed mode switches. Special thanks to Magnus Lind for patches that added this functionality.
Removed the 'bank' command from the debugger prompt, as it only worked (inconsistently) with certain bankswitch types. The bankswitch UI should now be used to query/set bank state.
Fixed bug in disassembly output; instructions at $F000 were never being highlighted during execution.
The UNIX configure script now supports newer versions of Hurd. Special thanks to Stephen Kitt for the patch.
July 1, 2014
Stella release 4.0 for Linux, MacOS X and Windows is now available.
Ported Stella to SDL2, which brings many new features. Among the largest improvements is native hardware acceleration support for Windows (Direct3D) and Linux/OSX (OpenGL). It is also now possible to port Stella to iOS and Android devices using OpenGLES. Hardware acceleration is now required, which means up-to-date drivers are needed. Software rendering is still present, but is somewhat unoptimized and unsupported going forward.
Fullscreen video modes now use the desktop resolution. Switching to fullscreen and back to windowed mode no longer rearranges icons on your desktop.
TIA TV effects are now available in all video modes, since hardware acceleration is a requirement.
Added a much more detailed view of cart extended RAM to a new debugger tab. Special thanks to SpiceWare for this implementation.
Added preliminary support for 'DASH' bankswitching scheme by A. Davie.
The AtariVox and SaveKey controllers now have the ability in the debugger to completely erase the virtual EEPROM data.
Added 'savesnap' debugger prompt command, and also associated context menu item to the debugger TIA output area. This saves the current TIA image to a PNG file.
Added 'hidecursor' commandline option, which allows to completely disable showing the mouse cursor (useful on systems that don't have a mouse).
Removed 'uipalette' option, as the original palette is no longer supported.
Updated included PNG library to latest stable version.
January 20, 2014
Stella release 3.9.3 for Linux, MacOS X and Windows is now available.
Added bankswitch schemes BF, BFSC, DF, DFSC and 4KSC, thanks to RevEng and CPUWIZ of AtariAge.
Updated ROM properties for several ROMs, thanks to Omegamatrix of AtariAge.
Fixed program crash when specifying a bankswitch type that Stella didn't recognize; an error message is now displayed.
August 31, 2013
Stella release 3.9.2 for Linux, MacOS X and Windows is now available.
Improved parsing of the DASM lst file for the debugger disassembly; it sometimes missed constant declarations.
Changed 'usemouse' argument from a true/false option to accept 'always', 'analog' and 'never'. This allows to use the mouse as a controller under more specific circumstances. The default is 'analog', which means the mouse is only used to emulate analog-like devices (paddles, trackball, etc).
Added ability to use bold fonts within the debugger window, which can be set with the 'dbg.fontstyle' commandline argument as well as in the debugger UI Settings dialog. This is useful for those that find the current font too narrow.
Renamed 'debuggerres' argument to 'dbg.res'. All future debugger- specific options will start with 'dbg.'.
The TIA 'zoom' area in the debugger now supports scrolling the mouse wheel (currently up/down only, as I don't have a sideways scrolling mouse to test with).
August 21, 2013
Stella release 3.9.1 for Linux, MacOS X and Windows is now available.
Note: because of TIA/6502 changes, the state file format has changed again, and old state files will not work with this release.
Several bugfixes and improvements to the debugger:Improved display of debugger when using larger video modes. There are now three font sizes, which are automatically selected when the debugger is sized accordingly. When using larger fonts, the extra space is now used more efficiently.
Fixed bug in disassembly when the mirror used for the current PC didn't match the mirror for the current bank. In this case, the disassembler became confused and didn't properly track the PC address.
Fixed bug in display of current TIA frame number in the UI; depending on how breakpoints were set, it was sometimes off by one.
Fixed RAM widget Search/Compare textboxes; entering any data and then pressing 'Enter' / clicking 'OK' locked the UI until exiting and re-entering the debugger.
Changed display for various TIA position counters to decimal (from hex) in the TIA tab. Related to this, all data input widgets in the UI now have the ability to enter binary, decimal or hex values by using the proper leading character (\, #, $, respectively).
Added 'INTIM Clks' to the 'I/O' tab. which shows the number of clocks between each 'step' of the INTIM timer.
Added ability to modify 'tiadriven' commandline argument to the 'TIA' tab, and 'ramrandom' to the 'I/O' tab. These options were available for quite some time, but they weren't exposed in the UI.
Added 'cpurandom' commandline argument, and associated UI item to the 'I/O' tab. This works similar to 'ramrandom', and randomizes the contents of the CPU registers on ROM startup.
Added 'uhex' debugger prompt command, which toggles all hexadecimal display between upper/lower case. This setting is also saved in the settings file as argument 'dbg.uhex'.
Removed 'loadsym' command from the debugger prompt, since the DASM symbol file is always loaded anyway, making the command redundant. Related to this, fixed loading symbols with ###.name convention; the leading number is now stripped.
Added support for DASM lst files (created with the -l option). For now, the contents are only partially used, to detect constants vs. symbolic addresses in the symbol file. Eventually, further information from the lst file may be used.
The GRPx and PFx registers in the TIA output now show inactive background pixels as either blanked or with the underlying object colour, instead of always being black. This gives a more accurate representation of how the registers are actually drawn onscreen. Thanks to Tjoppen of AtariAge for this idea and sample code.
The 'Source Address' locations for the CPU registers now show labels where appropriate.
Renamed 'Override properties' dialog (accessible from the ROM launcher by a right-mouse-button click) to 'Power-on options', with the following new options:Set start-up state for both joysticks as well as console select/ reset buttons. Related to this, added 'holdjoy01' and 'holdjoy1' commandline arguments, and removed 'holdbutton0' argument.
The ability to load the ROM directly from this dialog, after changing any settings, and also to start in the debugger.
Added more detailed information as to how to use this functionality to the UI.
Buttons held down are reset approx. 0.5 seconds after starting the ROM, to simulate pressing and releasing the buttons on a real console.
Fixed bug when using event remapping; changes were being saved only when launching a ROM from the launcher, not in standalone mode.
Improved bankswitch autodetection for newer EF and EFSC ROMs generated by batari Basic, thanks to RevEng of AtariAge.
Added properties database info for "Princess Rescue" ROM.
For the Linux/UNIX port:Fixed bug whereby a maximize button was always present in the window title bar. Stella could not be expanded in this way, so the button was removed.
Added Startup notification protocol patch to the .desktop file from Dan Fandrich.
Updated included PNG library to latest stable version.
June 27, 2013
Stella release 3.9 for Linux, MacOS X and Windows is now available.
Greatly extended functionality of the debugger disassembly:There is now a new tab which lists information specific to the cartridge bankswitching scheme in use. This includes the ability to modify internal state even for esoteric ROMs which don't follow the standard layout of 4K per bank.
The debugger now generates DASM-compatible disassembled code, which can be saved to an external file. This disassembly is based on both a static and runtime analysis, and is extremely accurate. It also automatically differentiates between CODE/PGFX/GFX/DATA/ROW areas, whereas normal Distella only differentiates between CODE/GFX/ROW. For now, only single-bank (4K and smaller) ROMs are supported; support for multi-bank ROMs will come in a future release.
The disassembly now recognizes various TIA/RIOT read/write mirrors, and marks them as such (for example, INPT4|$30 instead of INPT4 for address $3C). Special thanks to Omegamatrix for sample code and idea for this feature.
ROMS less than 2K in size (so called 'Sub2K' ROMs) now show only the actual data in the binary. This means, for example, that a 256 byte ROM will show only 256 bytes in the disassembly, instead of padding duplicated data to 2K boundary.
Fixed bug when entering patched bytes; the current number base wasn't being used.
Fixed labelling in ROW directives; it wasn't accurately setting a label in the case where it occurred in the middle of the data.
Added a new dialog for changing Distella settings, located by right-clicking the disassembly code.
The commandline option 'dis.resolvedata' has been renamed to 'dis.resolve', with new usage (see manual for further details).
Fixed regression in handling ZIP files (as compared to version 3.7.5) created with newer versions of the ZIP program. Related to this, added better error messages for invalid/missing/unreadable ROM files.
Added 'snapname' commandline argument and associated UI item, for specifying whether snapshots should be saved using either the internal ROM database name or the actual ROM filename. This feature was present in older releases of Stella, and due to popular demand it's now back again. Related to this, added a new dialog specifically for the numerous snapshot-related items.
Fixed bug in Linux/OSX versions when starting Stella for the first time; it was previously creating mislabeled directories to store settings, snapshots, etc.
Fixed redundant "New console created" message when entering the same ROM multiple times from the ROM launcher.
Updated profile database for "BasketBall" ROMs; the joysticks are now swapped by default, which allows one and two-player games to work correctly.
SuperCharger/AR ROMs now ignore the 'ramrandom' setting, and start with RAM containing all zeroes. This seems to fix issues with Dragonstomper always starting in exactly the same state.
Fixed issue when debugging CompuMate ROMs; keystrokes entered while debugging would be interpreted as typing on the CompuMate keyboard.
Changed colour of the 'current PC indicator' in the debugger to match the one used for line selection. This makes it easier to see for those with problems seeing lighter colours.
Improved functionality of the various pop-up dialogs and context menus in the UI; they can now be navigated more fully by the keyboard and mouse.
Updated internal ROM properties database to ROM-Hunter version 9 (thanks go to RomHunter for his tireless research in this area). Related to this, updated the snapshot collection.
Updated included PNG and ZLIB libraries to latest stable version.
March 13, 2013
The Subversion repository used by Stella has been changed. All developers will need to checkout again from trunk, or relocate their current directory to the new system.
March 3, 2013
Stella release 3.8.1 for Linux, MacOS X and Windows is now available.
Added support for TIA RSYNC writes, thanks to Omegamatrix of AtariAge. This allows the recently released "Extra Terrestrials" ROM to run, as well as improving emulation of "Fatal Run" and several other test ROMs.
Fixed typo in TIA HMOVE writes, thanks to Thomas Jentzsch. This fixes the constant collision issues in "Kool-Aid Man", and several other homebrew ROMs.
Fixed sound issues on OSX PPC machines (all sound was in little-endian format, but PPC is big-endian).
The OSX DMG archive now contains proper modification dates.
February 23, 2013
Added an expanded explanation for first-time developers to the Development section of the Stella webpage.
February 21, 2013
Stella release 3.8 for Linux, MacOS X and Windows is now available.
Huge changes to the sound system:The sound code now uses 16-bit signed samples instead of 8-bit unsigned samples, making it more compatible with a wider variety of systems.
Improved sound output for several ROMs, including "Space Rocks" (the 'heartbeat' sound can now be clearly heard).
The 'volume clipping' option has been removed, since in 16-bit mode it's no longer needed.
The 'Tia freq' option has been removed.
Selecting more common sample rates (other than 31400) now works much better, but there are still a few ROMS (like Quadrun) where 31400Hz still works best.
Many changes to handling ZIP archives:Files in multiple levels are now recognized. This fixes issues in Windows where such files couldn't be loaded at all, and in all systems where ROMs with the same name (but in different directories) weren't being recognized.
ZIP contents are now handled more intelligently. Archives containing only one ROM are automatically loaded, whereas those with multiple files are treated as directories.
Opening an archive from the commandline now works as in the UI, where opening a multi-ROM archive will pop up the UI and show the archive contents (as a directory).
The ZIP code behind the scenes is now much faster by making use of caching (the old code was actually from 1998!).
This new 'archive' infrastructure may eventually lead to 7-Zip support, as well as 'virtual' formats (such as showing the list of files for 2in1/4in1/8in1/etc within the UI).
Improved bankswitch autodetection for FA2 ROMs; 29K and 32K versions (meant for Harmony cart) are now recognized.
Improved bankswitch autodetection for X07 ROMs (although there's only two known ROMs in existence, so the detection probably isn't robust).
Tweaked bankswitch autodetection for the 0840, F8 and FE schemes; several homebrews that didn't run before now work correctly.
Fixed regression in RIOT INTIM reads; at least one known ROM (Mr. Roboto Berzerk hack) wasn't working properly.
Fixed bug in the debugger with RIOT INTIM/TIMINT display; reads were being done multiple times, changing the state of the registers and resulting in incorrect emulation.
Worked around bug in debugger disassembly of zero-page RAM; for now, the resolving of address vs. data sections is turned off in such a case. This fixes lockups in 'Meltdown' ROM.
Added support for different directories for saving/loading PNG files. These are set with the 'snapsavedir' and 'snaploaddir' commandline arguments (which replace the old 'snapdir'), and are also available within the UI.
Changed 'eepromdir' commandline argument to 'nvramdir', and changed the default location to BASEDIR/nvram (where BASEDIR depends on your OS). This means all your EEPROM and Flash files will have to be manually moved to this new directory. This affects developers, and those people playing ROMs with AtariVox/SaveKey support as well as the newer 'Star Castle' FA2 ROMs.
Updated included PNG and ZLIB libraries to latest stable version.
December 22, 2012
Stella release 3.7.5 for Linux, MacOS X and Windows is now available.
Improved regressions in PAL format autodetection, introduced in the past several releases.
Fixed crash when loading invalid PNG files in ROM browser.
Snapshots generated by Stella now include more informative info, such as the build number, platform architecture, TV effects in use, etc.
October 31, 2012
Stella release 3.7.4 for Linux, MacOS X and Windows is now available.
Fixed screen blanking regression in 'Video Chess', and improved behaviour of ROMs that don't use VSYNC.
October 26, 2012
Stella release 3.7.3 for Linux, MacOS X and Windows is now available.
Note: because of TIA/RIOT changes, the state file format has changed again, and old state files will not work with this release.
Improved handling of 'illegal' VSYNC signals, which sometimes created 'short' frames that caused massive flickering. Also improved related behaviour when VSYNC isn't used at all.
Improved sound generation with ROMs that have irregular scanline counts. This fixes many demo ROMs as well as Quadrun, where previously there would be 'gaps' in the sound output.
Improved emulation of RIOT chip, in particular the behaviour of reading from TIMINT. Also, D6 of the Interrupt Flag register is now properly set on active transition of the PA7 pin.
Fixed bug in DPC+ bankswitch scheme; the music in several ROMS wasn't playing correctly.
The ROM properties database now uses 'Auto' instead of 'Auto-select' everywhere. This makes for less typing when running from the commandline.
Updated included PNG library to latest stable version.
June 10, 2012
Stella release 3.7.2 for Linux, MacOS X and Windows is now available.
Fixed bug in handling filenames with the '~' character, as is used extensively by RomHunter rom-sets.
June 8, 2012
Stella release 3.7.1 for Linux, MacOS X and Windows is now available.
Note: because of TIA changes, the state file format has changed again, and old state files will not work with this release.
Improved TIA emulation with ROMs that have too few or too many scanlines; the output is now more accurate compared to a real TV. Special thanks to Omegamatrix of AtariAge for test ROMs in this area.
Modified hotkey for "Change console palette" (Control-f) to also change the display properties of the TIA. This allows you to switch between NTSC/PAL/SECAM (and variant) modes dynamically. Related to this, added Shift-Control-f key to step backwards through the available modes.
Added '64in1' and '128in1' multicart bankswitching schemes, which work the same as the 2in1/4in1/etc ones (Control-r switches to each consecutive game in the ROM).
Fixed several bugs in DPC+ bankswitching scheme, including ability to load and save state files. As well, ROMs now work correctly after console format autodetection.
Fixed bugs in handling relative filenames on the commandline, introduced in the last release. The new functionality should be much more robust.
June 1, 2012
Stella release 3.7 for Linux, MacOS X and Windows is now available.
Added Blargg TV effects, with presets for Composite, S-video, RGB, and badly adjusted TV, and well as a custom mode with full configurability of contrast, brightness, gamma, etc. Many keyboard shortcuts and commandline arguments were added to support this; see the documentation for a detailed explanation. These effects are OpenGL-only. Special thanks to Ian Bogost and the Georgia Tech Atari Team for the preliminary implementation.
Updated the CompuMate keyboard handler to recognize more keys on an actual keyboard, instead of having to remember the weird combinations used on the original CompuMate keyboard (although those original keys will continue to work). Related to this, fixed bug whereby 'ghost keys' would be detected by the CompuMate, particularly after pressing 'Enter' to start a game from the ROM launcher.
Added emulation for MindLink controller using the mouse; the 'Bionic Breakthrough' and 'Telepathy' ROMs now work.
Updated FA2 bankswitch scheme (Star Castle) to emulate load/save high score functionality to the Harmony cart flash RAM.
Added ability for ROM launcher to 'descend' into ZIP files when it contains more than one ROM file. This means you no longer have to unzip a multi-file archive before using each ROM. Thanks go to Roland Schabenberger (webOS maintainer) for this idea and sample code.
Several improvements to the debugger/disassembler:The 'resolvedata', 'showaddr' and 'gfxformat' commandline arguments are renamed to start with 'dis', indicating that they're used with the built-in disassembler.
Zero-page code addresses no longer have their high-byte truncated, and system equates (TIA and I/O registers) are now properly marked as such.
The Distella '-r' option (Relocate calls out of address range) is no longer the default, resulting in output more consistent with normal usage of Distella. Related to this, added the '-dis.relocate' commandline argument (and associated UI item) to toggle this dynamically.
Fixed bug in EFSC bankswitch scheme state saving; the Superchip RAM wasn't actually being loaded and saved to state files.
Improved speed of loading and saving state files, as well as slightly reducing their size. Because of this, old state files will not work with this release.
Replaced commandline argument 'uselauncher' with 'exitlauncher'. The new option specifies the behaviour of the ROM launcher when exiting a ROM (always exit to launcher, or only when the launcher was actually used). This setting can now be changed in the GUI.
Several updates to the internal properties database:'Juno First' ROMs now use an AtariVox/SaveKey when possible
'Astroblast' ROMs now use the paddles by default
'Star Castle 2600' ROMs added
Changed key-combo for enabling TIA objects and collisions to be toggled on and off with the Alt-period and Shift-Alt-period respectively (instead of having two separate keys to turn them on and off).
When working on the commandline, relative filenames are now correctly handled (current working directory is used).
The Windows 98/ME/2000 builds have been discontinued, due to code and features that are only available on Windows XP/SP3 and later.
Updated included PNG library to latest stable version.
March 30, 2012
Stella release 3.6.1 for Linux, MacOS X and Windows is now available.
Extended FA2 bankswitch scheme to handle 28K ROMs (in addition to the previously supported 24K ROMs).
March 16, 2012
Stella release 3.6 for Linux, MacOS X and Windows is now available.
Added support for 2600-daptor II device, including native support for 7800 controllers, BoosterGrip and Keypad controllers. Special thanks go to Tom Hafner for a complimentary test sample of this device, and also for donating a BoosterGrip controller.
Added ability to dynamically swap the port order of Stelladaptor/ 2600-daptor devices with the 'Control-1' key combo (useful if you have only one 2600-daptor and want to use it as a left port normally, but as a right port for Star Raiders, etc).
Added CompuMate bankswitching/controller support to the emulation core; the Spectravideo CompuMate ROMs (NTSC and PAL) now work. Frequently used keys on the CompuMate are directly mapped to your keyboard (ie, Func-Space for backspace is mapped to Backspace, etc). Loading/saving from the cassette player is not yet supported, and will come in a future release.
Fixed bug in BoosterGrip controller emulation; the functionality of the booster and trigger buttons was reversed. Related to this, renamed these actions in the Event Mapping dialog to be more clear.
Reverted to SDL 1.2.14 for the Windows 98/2k release, since SDL 1.2.15 isn't supported in that environment.
Updated included PNG library to latest stable version.
February 21, 2012
Stella release 3.5.5 for Linux, MacOS X and Windows is now available.
Due to changes in the debugger, old state files will not work with this release.
Fixed bug in sound restructuring introduced in the last release; in some cases, there could be some sound 'crackling' when starting a ROM after at least one ROM had already been loaded.
Several significant improvements to the debugger I/O tab:added controller input widgets for many of the built-in controllers, allowing to control joysticks, paddles, etc from within the debugger.
added ability to modify the SWCHB/SWBCNT port B registers.
added ability to view TIA INPTx and VBLANK latch/dump bits.
Reworked 'mcontrol' argument, and added ability to map the mouse axes separately for paddles 0-3 or driving controllers 0-1. In such modes, the left mouse button is tied to the x-axis, and the right button is tied to the y-axis.
Mouse 'specific-axis' mode is now saved per-ROM, meaning that each ROM can have separate settings. For example, this allows one ROM to use paddles 0 and 1, while another can use paddles 0 and 2, etc.
The key-combo for switching the mouse between controller modes is now 'Control-0' (Control-1,2,3 have been removed). This switches between all possible modes for the current virtual controllers.
Fixed bug in 'Fixed Debug Colors' mode; under certain circumstances, playfield graphics could be coloured as being player graphics.
Fixed bug in PAL color-loss setting in Video Settings; changing the settings wouldn't take effect until the ROM was reloaded.
Fixed bugs with cheatcode handling; loading a ROM with a cheat disabled would sometimes trash the emulation. More work is required in this area, including the ability to create more advanced types of cheats.
Updated ROM properties database for all Sega Genesis controller compatible ROMs. Also, the mouse can now emulate a Genesis controller, with the left/right buttons mapped to buttons B and C, respectively.
Added 'FA2' bankswitch scheme, thanks to code from Chris D. Walton. This scheme will be used in an upcoming 'Star Castle' ROM.
Updated internal ROM properties database to ROM-Hunter version 7 (thanks go to RomHunter for his tireless research in this area).
Added several PERL tools to help in automation of analyzing RomHunter ROM set releases.
Fixed compile issues in Irix when using the default compiler instead of gcc. Thanks go to Rainer M. Canavan for this code.
Updated included PNG library to latest stable version.
December 29, 2011
Stella release 3.5 for Linux, MacOS X and Windows is now available.
Stella is now DonationWare! Please see the DonationWare link on the main webpage for more information.
Added several improvements to the joystick management code. Joystick event mapping is now saved per device, meaning that if you map events to a certain joystick device, remove the device and then later insert it again, Stella will remember the original mapping.
The total number of joysticks present and their associated properties (number of axes, buttons and hats) is now dynamic. That is, there's no longer a hard-coded limit on the number of joysticks that Stella can use, or the number of buttons, etc that it contains. This fixes a serious bug with PS3 controllers with 27 buttons, whereby adding a mapping for joystick 0 would inadvertantly change settings for joystick 1, and could potentially lead to a program crash.
Added 'mcontrol' commandline argument, which can specify to use each mouse axis as a separate paddle. The old (and default) behaviour can be activated by setting this argument to 'auto'. Related to this, removed redundant 'usemouse' argument.
Huge restructuring of the OpenGL code, making it compatible with OpenGL 2.x+ features (such as vertex buffer objects), while at the same time keeping compatibility with OpenGL 1.5 / OpenGL ES. Because of the required changes, TV effects were removed (they will be added again for the next release).
Improvements to audio handling, particularly for certain cases of Windows, ATI video cards, and OpenGL mode. The sound device is now opened only once when Stella starts, and is paused between loading different ROMs. This fixes a problem whereby sound could possibly not be functional after loading the first ROM. Related to this, removed the 'audiofirst' commandline argument as it's now redundant.
Fixed bug with displaying the ROM launcher in Windows XP; the initial load was sometimes taking up to 30 seconds to complete.
Added logging facility, whereby the output of the application is available within Stella itself. This can still be printed to the console, or also saved to a file. Add the 'loglevel' and 'logtoconsole' commandline arguments which control these settings, and removed the 'showinfo' argument as it's now redundant.
Updated DPC+ bankswitching scheme to latest code provided by SpiceWare.
Added MAMCR handling to the Thumb ARM emulation code. Note that MAMCR isn't actually emulated, it is just ignored for now. This fixes a bug whereby accessing MAMCR would crash the ARM emulation.
Added 'thumb.trapfatal' commandline argument, which causes the Thumb ARM emulation to either trap on a fatal error (throw an exception to the debugger and exit emulation) or simply log the error and continue. This should normally always be enabled, but can be disabled by developers for testing reasons.
Updated default snapshot directory to be much saner and easier to find. For most systems, it now defaults to the users 'Desktop'. Note that the commandline argument has changed to 'snapdir'.
The debugger 'print' command now indicates "special" addresses if they are read-only (R), write-only (W) or read-write (R/W).
Fixed a bug where scrolling the mouse-wheel in certain debugger UI items would cause the program to crash; scrolling now works as expected.
Fixed minor display issue in the debugger RAM area; some addresses were being displayed as '...'.
Fixed compile issues in the latest versions of Ubuntu and Debian, and fixed UNIX desktop file so that Stella will launch with a ROM when selected from its icon. Thanks go to Stephen Kitt for this code.
Updated included PNG library to latest stable version.
Updated the credits list in the documentation, listing people that have donated hardware to the Stella team.
June 11, 2011
Stella release 3.4.1 for Linux, MacOS X and Windows is now available.
Re-enabled 'grabmouse' commandline argument and associated functionality with the following changes:it is changed in the "Input Settings' UI, not in 'Video Settings'
it only has meaning while in emulation mode
it is enabled by default
Fixed bug with emulation of paddles using the mouse most evident in Warlords; movement was being filtered out if the mouse was moved too fast. There's still more work required in this area, however.
Fixed bug with analog axes on gamepad devices, whereby jittering in these axes would override input from digital axis, hat or keyboard input.
Fixed bug when switching to the debugger and back again would sometimes cause an extra mouse motion event (which would cause the emulation to think the mouse was moved and move the player accordingly).
Tweaked bankswitch autodetection code for 4A50 bankswitching; several more test ROMs are automatically detected.
The 'saverom' debugger command now saves ROMs in your home directory by default if you don't specify a valid path. This fixes a bug whereby ROMs were saved in strange locations and couldn't later be found.
Fixed bug in automatically executing the debugger 'autoexec.stella' file; any commands it contained weren't actually being executed.
Zero-byte ROMs are no longer loaded and mis-detected as Supercharger images.
May 29, 2011
Stella release 3.4 for Linux, MacOS X and Windows is now available.
Many improvements to input handling, particularly with the mouse and paddles:The mouse can now be used to emulate a joystick, booster-grip or driving controller.
The mouse now controls only one device at a time (1 of 4 paddles, 1 of 2 joysticks, etc), instead of devices from both virtual ports.
The sensitivity for digital and mouse input (for paddles) can now be set separately with the 'dsense' and 'msense' commandline arguments, and from within the Input Settings UI.
Added new controller types 'Paddles_IAxis', 'Paddles_IDir', and 'Paddles_IAxDr', which invert the paddle axis, direction, and axis+direction, respectively. These are used for certain ROMs that have the axis or direction inverted from normal (for example, using the paddles causes on onscreen object to move up and down vs. left and right). All applicable ROMs in the internal database have been updated.
Added preliminary support for emulating ARM code to the DPC+ bankswitching scheme (thanks to Batari). Related to this, fatal errors in the DPC+ ARM code are now caught and shown in the debugger.
Updated internal ROM properties database to ROM-Hunter version 6 (thanks go to RomHunter for his tireless research in this area).
The ROM audit dialog now automatically selects the current directory in the ROM launcher, and reloads the directory after the audit is complete.
Removed the 'grabmouse' functionality; the mouse is now always grabbed while playing a game, and released otherwise.
Updated built-in version of the PNG library to the latest version.
November 12, 2010
Stella release 3.3 for Linux, MacOS X and Windows is now available.
Added the following Distella 'directives', which are used to override and specifically tell the debugger how to treat address space (CODE, GFX, PGFX, DATA, ROW). See the debugger documentation for more information.
Disassembly from the debugger is now tracked by the emulation core, and accented by the built-in Distella code. Basically, the emulation core knows when an address is referenced as code, making for very accurate disassembled output. Related to this, the emulation core now tracks accesses to GRPx and PFx registers, automatically marking the addresses as GFX or PGFX sections. This will be improved in future releases, as there are many ways to store data in the graphics registers.
Improved output of graphics output in the disassembler, by marking such addresses with a bitmap of the data they represent. This allows player graphics (GFX directive) and playfield graphics (PGFX directive) to really stand out in the disassembly. Related to this, added ability to edit such graphics in either binary or hexidecimal.
Added preliminary support for Distella configuration files. Much more work is required in this area, since Stella now contains directives that don't yet exist in the standalone Distella program. Configuration files are automatically loaded, and debugger commands now exist to load and save configuration directives directly from the debugger.
type (gives detailed info for disassembly type of an address)Added the following commands to the debugger prompt:clearconfig, listconfig, loadconfig, saveconfig
(used for Distella configuration files)
code, data, gfx, pgfx, row
(directives used to override automatic disassembly types)
jump (jumps to a specific address in the disassembly)
The debugger prompt commands 'trap', 'trapread' and 'trapwrite' now accept a range of addresses as well as a single address.
Added 'data source' address output for the CPU SP/A/X/Y registers. This is useful for quickly seeing what an operand address resolves into with various load commands.
Many commands in the debugger prompt are now case-insensitive; further improvements will be made in future releases.
Many improvements to the built-in Distella disassembler. When passing a relative branch or jump, data is now disassembled as code only if the emulation core hasn't detected it as data. Such 'preliminary' code is marked with a '*' in the disassembler, indicating that it is tentative code, and hasn't actually been executed yet. This allows to quickly see possible code paths, and at the same time eliminate disassembly of addresses that are never used as code sections.
Program counter/instruction addresses can now be toggled in the disassembly.
Disassembled instructions involving relative branches now show only one byte for the operand, not two bytes.
Fixed bug in several text input fields, whereby binary data couldn't be input (a '\' was required, but the character was blocked).
Fixed issues with PAL ROMs on screenmodes smaller than a PAL ROM would require. In this case, the image is centered and clipped to the screen resolution. This prevents the message "PAL ROM not supported" from appearing.
Fixed bug in fullscreen OpenGL mode when using ATI video cards; the desktop background was 'bleeding through', resulting in a very annoying flickering.
Fixed crashes when opening windows larger than the desktop resolution in fullscreen mode; this is now allowed only in windowed mode.
Application window centering now also works when switching between video modes, not just when starting the application.
Added support for building a Windows version compatible with Windows 98 and 2000 (compiled with Visual Studio 2005). Testing is very limited, since I no longer have access to these systems.
Fixed build issues for Innosetup in Windows XP.
Fixed bug in OSX version where the name of the application wasn't being shown in Activity Monitor.
State files from older versions will no longer work in this release, because of the extensive changes to the debugger and disassembler.
September 17, 2010
Stella release 3.2.2 for Linux, MacOS X and Windows is now available.
Fixed bug with window centering; if enabled and the the window was larger than the desktop, the window would be moved offscreen.
August 25, 2010
Stella release 3.2.1 for Linux, MacOS X and Windows is now available.
Improved behaviour of joystick 'hat' movement. This should fix bugs most visible in Yars' Revenge.
Fixed bug in debugger rewind states; bankswitching wasn't being performed during the rewind. Related to this, fixed a similar issue with the debugger 'loadstate' and 'savestate' commands.
Added game properties info for the newly released 'Halo 2600' ROM.
August 20, 2010
Added an FAQ (frequently asked questions) section to the Stella webpage.
August 20, 2010
Stella release 3.2 for Linux, MacOS X and Windows is now available.
NOTE: because of the many event-related changes in this release, all event mapping should be reset to defaults after starting Stella for the first time. As well, because of other internal changes, older save-state files are no longer valid.
Many improvements to joystick handling code, particularly for analog axes. Navigating the UI should be much smoother now, and remapping events to analog axes should be less 'twitchy'.
Added ability to assign and remap 'combo' events in emulation mode. Combo events are basically a sequence of normal events (up to 8) that are generated from a single event (ie, one button on a joystick could generate up to 8 events). Updated Input Settings UI to access and modify these events.
Default mappings are now available in UI and emulation mode for the first 'hat' detected on a joystick/gamepad. Related to this, a hat now works exactly like an axis in UI mode (holding down a direction continues that direction until the hat is released/centered).
Several major improvements to the debugger:the disassembler can now process multiple entry points, and caches entry points as they're encountered (ie, the disassembly isn't 'reset' each time a bank change occurs or you exit and re-enter the debugger)
preliminary support for disassembling from zero-page RAM
re-added ability to change banks with the 'bank' debugger prompt command and within the ROM disassembly UI
user labels in disassembly are now supported again
'runto' command is now case-insensitive, and shows a progressbar while searching through the disassembly
the debugger window can be resized between ROM loads (previously, the app had to be restarted)
fixed bug in Distella disassembler output, where it sometimes generated addresses above $FFFF
a vertical line separates the disassembly from the raw bytes
Fixed behaviour of SWCHB and SWBCNT; pins set to output now remember the values previously written. Some ROMs use this functionality for extra storage. Special thanks to Omegamatrix of AtariAge for advice and test ROMs in this area.
Fixed bug when reading from illegal TIA addresses; a Space Invaders hack was showing pink enemies instead of white ones. Again, special thanks to to Omegamatrix of AtariAge for advice and test ROMs in this area.
Fixed bug in handling INPT4/INPT5 latches from VBLANK; a least one ROM was working in Stella when it didn't on real hardware.
Added 'ramrandom' commandline argument, which is used to randomize all RAM in the system; otherwise, the RAM is zeroed.
Added 'finishing touches' to some of the UI descriptions, giving a better explanation of the functions. Related to this, certain options now show a message box explaining the option in further detail (particularly the ROM Audit mode). As well, when starting Stella for the first time, a prompt appears to select a ROM directory.
Fixed bugs in the ROM launcher when viewing certain PNG images not created by Stella. Related to this, the official PNG library is now included in the Stella codebase (version 1.4.3). Also added composite snapshots for those ROMs which consist of several games. Thanks go to Buzbard of AtariAge for these images.
Added several fixes for crashes on 'small' systems (those systems where the maximum resolution is less than 640x480).
Tweaked bankswitch autodetection for 0840, DPC+, E7 and UA schemes.
Improved F8 bankswitch autodetection for Yars Revenge in 8in1 ROM.
Updated DPC+ bankswitch scheme to latest specifications.
Snapshots taken in continuous snapshot mode are now timestamped, so older files are never overwritten.
Fixed a TIA segfault that could occur with certain ROMs.
The 'center' application window functionality can now be changed without having to restart the application. Related to this, mouse positioning bugs when using the Linux version in OpenGL mode with SDL 1.2.14 have been fixed.
Reworked the manual, dividing it into 'Getting Started' and 'Advanced Configuration' sections. It still contains the same info as before, but hopefully in a better organized way.
Updated Help dialog; it was showing incorrect info for some OSX shortcuts.
Updated OSX build script to not crash when a previous build is detected, and to properly handle filenames with spaces.
Updated included ZLib to latest release version (1.2.5).
May 3, 2010
Stella release 3.1.2 for Linux, MacOS X and Windows is now available.
Modified 'showinfo' command to accept levels of output, where increasingly larger numbers provide more debug output. Related to this, added UI item to modify 'showinfo'.
Updated DPC+ bankswitch scheme to latest specifications, including support for 32K ROMs with ARM code (the ARM code is ignored for now).
Fixed bug in saving patched ROMs using DPC and DPC+ bankswitch schemes; the saved image didn't actually include any changes made by the user.
Removed 'uselauncher' from the UI, since disabling it will remove the ROM launcher on all future runs, and not allow one to enable it again. It's still available from the commandline, for those that have a need for it.
April 26, 2010
Stella release 3.1.1 for Linux, MacOS X and Windows is now available.
Fixed program crash when using RIOT addresses and labels in the debugger console prompt.
Updated DPC+ bankswitch scheme to latest specifications.
April 22, 2010
Stella release 3.1 for Linux, MacOS X and Windows is now available.
Fixed a major bug with text drawing in software rendering mode. Switching between windowed and fullscreen mode while text was being shown could result in garbled text or even a program crash.
Fixed issues when using 'sleep' timing, whereby a lockup could occur when changing video modes, and/or Stella would consume more CPU time than was necessary.
Integrated Distella disassembler, completely replacing the previous disassembler. The entire infrastructure has not been completely ported yet. As a result, labels defined by the user or from a DASM symbol file aren't actually used in the disassembly, and almost all distella config options are disabled. These will be addressed in a future release.
Completely reworked the debugger cartridge interface, so that the disassembly is dynamic (ie, the debugger tracks when cart address space has changed, and automatically performs a re-disassembly).
All carts with extended RAM that differentiate between read and write ports now behave correctly when a read from the write port occurs.
Added more complete support for the more esoteric bankswitch schemes in the debugger. These schemes now support accurate disassembly and ROM patch functionality. Related to this, fixed a bug in disassembler view when a failure to patch a ROM still showed the (incorrect) patched results.
Added ability to disable TIA object collisions, independent of enabling/disabling the objects. Previously, one had to completely disable an object to avoid collisions, but now an object can be enabled (and seen) but still have its collisions disabled. These actions are tied to the same keys as the enable ones, except the 'Shift' key is also used.
Added preliminary support for 'DPC+' bankswitching scheme, thanks to Darrell Spice Jr and Fred Quimby.
Added '16in1' bankswitching scheme, which works with various ROMs labeled '128-in-1 ...' (the database has been updated for these). Related to this, switching between multicart ROMs for 2in1, 4in1, 8in1, 16in1 and 32in1 now shows a UI message indicating which ROM is active.
Reverted some of the TIA improvements with respect to 'starfield effect' as seen in "Cosmic Ark" and "Stay Frosty". The emulation is now more accurate as compared to the majority of consoles in use.
Added debugger pseudo-register '_rwport', which traps on a read from the write port. This differentiates from reads that are normally part of a write cycle (ie, it traps only on inadvertent reads).
Added 'resolvedata' commandline argument and associated UI item, used to set the "resolve data sections" config option in Distella (vs. treating all address space as code).
Added 'runtopc' debugger command, used to step until encountering the given program counter. This is also available in the ROM disassembly UI from the right-click context menu.
Added 'listfunctions' and 'delfunction' debugger commands to access/remove user-defined functions. Related to this, fixed a bug in 'function' command that could cause a program crash.
Added 'cls' debugger command, used to erase the text and history from the debugger prompt.
Removed the 'listwatches' and 'poke' debugger commands, as they were redundant.
Removed the 'loadlst' debugger command and the ability to use a DASM .lst file. This code was incomplete, and no longer fits with the recent disassembler improvements. Support for this may return in a future release.
Modified 'disasm' debugger command to accept a second argument indicating the number of lines to disassemble.
Improved tab-completion in the debugger prompt; it now completes on functions and pseudo-registers.
Added emulation of the "Sega Genesis" controller, with two buttons that are directly supported on a real system.
The ZLib library is now included in the core code, so Windows developers no longer have to track down the ZLIBWAPI archive.
Many changes to the MacOS X port, bringing it more in line with other systems:The application is now known as 'Stella' (instead of StellaOSX).
Two versions are available: the first is a 32-bit Universal Binary for OSX 10.4 - 10.6, and the second is 32/64-bit Intel-only for OSX 10.6 (aka Snow Leopard). The Intel version is compiled with the very latest compiler (LLVM/Clang), resulting in better performance.
The keyboard handling is changed to match other systems in terms of where the keys actually are on the keyboard (ie, the OSX Command key corresponds to Alt, and the OSX Control key corresponds to Control).
The application menu has been cleaned up and simplified, and it now shows the correct shortcuts for menu items.
The settings file is now (according to Apple standards) '~/Library/Preferences/Stella-emu.plist'.
The base directory (where all other Stella stuff is located) is now '~/Library/Application Support/Stella'.
Because of these changes, all your settings will have to be entered again.
Added 'ctrlcombo' commandline argument, which toggles the use of the control key as a modifier key. This is useful if you want to press 'Control' and 'R' in a two player game, and not have the combination treated as 'Control-R' (which will issue a ROM reload).
Added 'usemouse' commandline argument and associated UI item. This toggles the use of the mouse as a controller of any type.
Added 'uimessages' commandline argument and associated UI item. This toggles showing of UI messages overlaid on the screen. Critical messages are still shown, though.
Added ability to take multiple snapshots in a given interval every x seconds. This is currently tied to the 'Alt-s' key and is not remappable (for now). The interval can be set with the 'ssinterval' commandline argument and within the UI, and defaults to 2.
Many changes to the FrameBuffer and UI code for 'smaller' systems. Stella will now scale correctly to small screens, down to 320x240 (which is the absolute lower limit supported). Related to this, added 'maxres' commandline argument, which is useful for developers testing on such systems.
The About dialog now shows the version of SDL in use, and the type of CPU the application is running on (i386, x86_64, etc).
Improved 'listrominfo' commandline argument to list all information from Stella's internal ROM database, including a heading. This output can be imported into a spreadsheet or database program.
Renamed 'tiafloat' commandline argument to 'tiadriven'. The emulation of the behaviour of floating TIA pins is also much more accurate.
Reworked state files so that they're associated with the cartridge type used, not the MD5sum of the ROM. This is useful for developers, since the same state file can now be loaded from different ROMs, as long as the cart type stays the same. This also fixes a bug where loading from a non-existent state file could cause Stella to crash. Because of these changes, old state files will no longer work.
Fixed bug in certain editable text fields, where pressing Return/Enter would disable any further input.
September 11, 2009
Stella release 3.0 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available. Note that starting with this release, the oldest supported version of Windows is Windows 2000; support has been discontinued for Windows 95/98/ME. It's been at least 10 years guys, it's time to move on.
Huge updates to the TIA emulation system. Illegal HMOVEs are now handled correctly, resulting in improvements to many ROMs (thanks to Wilbert Pol for many ideas and code for these improvements). All HMOVE emulation 'cheats' were removed; the emulation is now cycle-exact in this area.
Improved emulation of the Cosmic Ark 'starfield effect', also used in Stay Frosty; the emulation now looks very accurate.
Many improvements to the normal TIA rendering code, fixing problems when disabling certain graphical objects (certain objects were being misdrawn when others were enabled/disabled).
Improved TIA collision handling in the non-displayable area of the screen; this fixes problems in RAMRacer ROM.
Improved TIA redraw problems/graphical garbage when ROMs generate many more scanlines than a real TV would allow; this fixes problems in Q-Bert and the recent Playaround demo.
Added 'Fixed Debug Colors' option similar to the no$26k emulator. This allows each graphical object to be drawn in a fixed color, more clearly showing how the objects interact. HMOVE blanks are also shown in a different color. The TIA now emulates a 7-color register model, allowing even shared objects to show different colors. This is toggled with the 'Alt Comma' key.
Related to 'Fixed Debug Colors', HMOVE blanks can now toggled during TIA display with the 'Alt-m' key.
Added rewind functionality to the debugger, where states are saved after each step/trace/scanline/frame advance. Pressing 'Alt-r' or clicking the new rewind button will undo up to 100 previous operations.
Added 'electron beam indicator' to the debugger TIA output. Basically, this is a visual pointer indicating the position of the electron gun when scanning the display.
Added ability to completely disable fullscreen mode, which fixes problems for some people where fullscreen mode was being entered even if it wasn't enabled.
Added '-joyallow4' commandline argument and associated UI item to allow all 4 directions to be pressed simultaneously on a joystick.
Improvements made to the ROM launcher: the backspace key now goes to the parent directory (this key can be remapped), and previously selected directories are now automatically selected.
Added support for 2IN1 bankswitching scheme, where two ROMs are present in one binary. Currently supported are 2, 4, 8, and 16K ROMs.
Added bankswitch support for the 6K version of Starpath/Supercharger ROMS. This allows the 6K version of Cubis to run.
Updated bankswitching schemes FASC and MB; they are now known as FA and F0, respectively. This naming brings Stella in line with other emulators and programming utilities.
Fixed editing of cheats in the Cheat Dialog; the old cheat wasn't being removed.
July 13, 2009
Due to somewhat popular demand (and the fact that I finally got Mandriva 2009 working in VirtualBox), the Mandriva RPMs are available again. Hopefully I can keep the VM working for future releases, but if anyone is interested in maintaining RPM builds for Mandriva, Fedora, etc, I'd really like to hear from you.
July 4, 2009
Stella release 2.8.4 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Fixed bug where Stella could lock up after running for ~71 minutes. Special thanks to Robert Tuccitto for bugtesting and feedback on this issue.
Updated UA bankswitch autodetection for Gingerbread Man ROM.
Updated 0840 bankswitch autodetection for Toyshop Trouble ROM.
The smallest ROM that Stella can support is 64 bytes; this lower limit is now tested when loading Sub2K ROMs.
Starting from this release onward, I will be providing Linux binaries for the latest version of Ubuntu only (currently, 32/64-bit Jaunty). The Mandriva RPMs are discontinued, but will probably be still available from the PLF repository. Sorry for any inconvenience this may cause, but I can no longer build, maintain or support packages for systems that I don't personally use.
June 25, 2009
Stella release 2.8.3 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Fixed OpenGL bug which caused an immediate program crash if the available OpenGL version was less than 2.0.
June 23, 2009
Stella release 2.8.2 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Fixed OpenGL detection bug which could disable OpenGL support entirely if TV effects are not available (version < 2.0), when in fact only the effects should have been disabled.
The '\' character can now be entered in UI text fields again. Related to this, strings containing '\' are now properly loaded and saved to various config files.
June 19, 2009
Stella release 2.8.1 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
NOTE: Windows users will have to reset their options or manually move their config folder in this release, since the location of the config files has changed.
Fixed OpenGL issue for some Windows users whereby the OpenGL TV effects weren't available, even if the available version of OpenGL was sufficient. Related to this, the OpenGL version found by Stella is now reported in the TV effects dialog.
Added fallback to software rendering when OpenGL rendering has been requested, but for whatever reason fails to initialize.
Added native support for 4in1, 8in1 and 32in1 multicart bankswitching schemes. When using these schemes, the 'Reload ROM' action (by default, Control-r) will switch between each game in the ROM.
Added bankswitch support for ROMs smaller than 2K in size. These will be treated as 2K ROMs natively, without having to manually 'pad' them to 2048 bytes.
Added preliminary suppport for autodetection of X07 bankswitching.
Tweaked PAL autodetection; it was marking some PAL ROMs as NTSC.
Changed default location for Stella config files in Windows to the users' APPDATA folder (for XP and Vista, this is '~/Application Data/Stella'). The '~' symbol now represents the users PROFILE/home directory, matching its usage in Linux and OSX. The ability to override this with 'basedir.txt' is still available, but not advised.
Changed '-exitlauncher' commandline argument to '-uselauncher'. This works as before except the launcher is never used at all if the option is set to false.
Fixed crash when launching Stella from the commandline and giving a directory name instead of a rom filename.
June 9, 2009
Stella release 2.8 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Added CRT simulation effects as described in the AtariAge posting CRT emulation for Stella. For now, this requires OpenGL 2.0 or greater with support for GLSL (GL Shading Language). This code will be expanded on and optimized in future releases.
Adding editing of extended RAM in the debugger RAM UI. The RAM 'spreadsheet' now shows the entire address space of RAM in the system, in 128 byte increments. The first bank shown is zero-page, with the others following in consecutive order. The UI takes care of read vs. write port differences, so you don't have to worry about the offsets. For now, all SuperChip based ROMs (EFSC, F4SC, F6SC, F8SC) as well as 3E, CV, E7 and FASC are supported.
All ROMs which include SC extended RAM will now have memory erased if you attempt to read from the write port. Related to this, entering/exiting the debugger will no longer erase the extended RAM.
Patching of ROM for bankswitch types 0840, SB, UA and X07 is now implemented, but hasn't been extensively tested.
Visual improvements to the CPU register UI in the debugger; the SP/A/X/Y registers now have separate decimal and binary views.
Tweaked paddle control so that all positions are reachable in game 4 of Activision Casino in both NTSC and PAL versions.
SuperCharger/AR ROMs now start with a random value in the CPU accumulator. This should fix issues with Dragonstomper always starting in exactly the same state.
Auto-detection for '3F' bankswitching improved; several ROMs previously detected as 'F8' now work correctly.
Updated internal ROM properties database to ROM-Hunter version 5 (thanks go to RomHunter for his tireless research in this area).
Added '-exitlauncher' commandline argument and associated UI item, to specify what happens when you exit a ROM. Normally, exiting a ROM brings up the ROM launcher, but this can be disabled for those using an external frontend (in which case exiting a ROM also exits from Stella).
Re-added '-fastscbios' commandline argument, and added an associated UI item. When enabled, the SuperCharger load bars are now completely removed (and not just sped up as in previous releases).
The '-listrominfo' commandline argument now shows all ROM information built in to the internal database, taking into account any information in 'personal' stella.pro files.
May 16, 2009
Major website update using newer technologies (PHP and CSS). Updated many dead links, and added a new 'Homebrew Developers' section. Special thanks go to Andrew Kator () for providing the PHP/CSS code.
May 12, 2009
The Stella repository has now been fully converted to Subversion. All developers currently using CVS should switch over to SVN immediately.
May 1, 2009
Stella release 2.7.7 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Corrected emulation of CPU opcodes involving 'decimal' mode (ADC/RRA and SBC/ISB). Special thanks to SeaGtGruff and others on the Stella mailing list for in-depth discussion and creation of test ROMs.
Fixed bug in F4SC bankswitching mode; writes to bankswitch addresses weren't triggering a bank switch.
Changed internal sound frequency of Pitfall 2 from 15.75KHz to 20KHz, as this sounds much more authentic when compared to a real cartridge.
April 14, 2009
Stella release 2.7.6 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Added support for 'EF' bankswitching (Paul Slocum Homestar Runner), as well as auto-detection of this format.
Added support for 'EFSC' bankswitching, as well as auto-detection of this format. This is similar to the 'EF' scheme, but also includes 128 bytes SuperChip RAM.
Added autodetection for '0840' and 'SB' bankswitching formats.
Improved autodetection for 'UA' bankswitching format.
Fixed bug in selecting video modes larger than the current screen; the resulting video mode will now be the largest one available (previously it selected the smallest one available).
The currently selected CPU register now displays its value in decimal and binary (in addition to hex) in the debugger.
March 27, 2009
Stella release 2.7.5 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
After about 2 years, finally fixed the infamous 'red screen' issue when using ATI video cards in OpenGL mode in Windows. In the end, it was determined to be a bug in the ATI drivers. Special thanks go to Ant () for bugtesting and constant feedback wrt this bug.
Fixed bug in TIA SCORE mode emulation when the Priority bit is also set. This fixes a very noticable graphical glitch in 'Swordquest Waterworld', as well as minor glitches in several other ROMs such as 'Space Shuttle'.
Treat spaces as normal characters in the ROM launcher. This means that ROMs with spaces can be located with quick selection (ie, typing characters will automatically jump to a ROM with that name, and typing 'space' won't cause the launcher to jump back to the top of the list).
The debugger window can now have a minimum height of 620 lines (previously the minimum was 690), but you lose access to the TIA 'RAM' bytes when using this resolution. This should allow it to work better on devices with small displays.
February 9, 2009
Stella release 2.7.3a for Windows is now available.
Fixed minor issue in 2.7.3 with basedir.txt functionality; the pathnames can now contain spaces.
February 9, 2009
Stella release 2.7.3 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Fixed rendering issues in software mode when using 24-bit colour depth. This isn't as fast as 16 or 32-bit modes, so you're recommended to use one of those whenever possible.
For the Win32 port: re-added ability to change the default location for storing Stella config files. To use this, simply create a file named 'basedir.txt' in the application directory containing the full path where all Stella-related items should be stored.
Tweaked the TIA info statistics overlay to be smaller while still including all relevant information.
January 27, 2009
Stella release 2.7.2 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Fixed major bug in ROM Audit functionality; renaming ROMs would create files without an extension.
January 26, 2009
Stella release 2.7.1 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Partial workaround for sound not working in OpenGL video mode in Windows with ATI video hardware. Sound will now work for the first ROM selected, but not for subsequent ones (you will have to quit and restart Stella for sound to work again). Related to this, added '-audiofirst' commandline argument, which initializes audio before video when emulating a ROM. Further work is required to completely fix this bug.
Fixed bug where volume wasn't being saved in 'Audio Settings' when started from the ROM launcher.
Fixed crash which sometimes occurred when viewing snapshots in the ROM Info viewer.
Allow setting window sizes for the ROM launcher and debugger to be larger than your desktop resolution. Be careful with this feature, as switching to fullscreen mode may cause problems in such cases.
Made the ROM launcher filename filtering be case-insensitive. This fixes a bug whereby ROMs with uppercase extensions were marked as invalid.
Added a pattern matching textbox to the ROM launcher, used to further filter the files shown in the listing. For now, this filters files only (directories are not filtered, and are always shown).
The location of EEPROM files used for AtariVox/Savekey emulation can now be changed with the '-eepromdir' commandline argument as well as in the UI.
Added '-gl_aspectn' and '-gl_aspectp' commandline arguments (and associated UI items), which replace the previous '-gl_aspect' setting. The aspect modes can now be set separately for NTSC and PAL mode. Related to this, the range of values is now 80 - 120.
Fixed bug with hold-select/reset/button0 when overriding ROM properties; the checkboxes in the UI weren't actually doing anything.
The 'grabmouse' option is now configurable from the UI; previously it was only accessible from the commandline or its shortcut key.
Removed 'Emulation_HmoveBlanks' ROM property and associated UI item. You can no longer optionally turn off HMOVE blanking; it is always enabled when necessary.
January 19, 2009
Stella release 2.7 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Totally reworked the built-in UI to be font-sensitive and use higher-resolution fonts. Stella now requires a minimum screen size of 640x480. If used in a resolution smaller than that, the fonts will be reduced accordingly. Related to this, switching between software and OpenGL rendering now requires an application restart.
Added three different sized fonts (small, medium, large) which can be used in the ROM launcher.
Added ability to temporarily override ROM properties from the UI. This is tied to a right mouse button context menu in the ROM launcher, and is very useful when you want to use a set of properties for all subsequent ROMs without having to manually change each one.
Added ability to filter the files shown in the ROM launcher. Currently, the choices are 'all files', 'all roms', or 'roms ending with a certain extension'. This functionality is tied to a right mouse button context menu in the ROM launcher. Extensions can also be set with the '-launcherexts' commandline argument.
Added ability to reload the listing in the ROM launcher, either from a right mouse button context menu or pressing the Control/Cmd-R key.
Made the ROM info viewer in the ROM launcher configurable to show snapshots in 1x or 2x mode.
Made the delay between consecutive keys being recognized as one word configurable in the ROM launcher. This is useful if you find that you have to press keys too quickly to jump to a specific ROM. This can be set in the UI or using the '-listdelay' commandline argument.
Updated internal ROM properties database to ROM-Hunter version 4 (thanks go to RomHunter for his tireless research in this area).
Expanded the statistics overlay for the TIA image to also show Display Format and Bankswitch type information.
Added '-ss1x' commandline argument and associated UI item, used to generate snapshots in 1x mode, independent of the filtering/scaling currently in use.
Various path textboxes in the UI now recognize './' (or '.\') to mean the current directory and '~/' (or '~\') to mean your home directory (for Windows, home directory will be your 'My Documents' folder).
Large speedup in loading directories with many files in the ROM launcher.
Fixed reset issue in 3E, 4A50, AR, CV, E7, F4SC, F6SC, F8SC, FASC and MC ROMs; the internal RAM wasn't being randomized after the initial reset.
M6532/RIOT RAM is now randomized at every reset, not just when the emulation starts.
Fixed bug in _diff pseudo-registers in the debugger; they were actually defined backwards.
Added fix for 'Challenge/Surfers Delight' ROM; the startup bank was incorrect. Combined with the new 'Override Properties' functionality, you can now play both games directly from the UI (no need to use the commandline).
Fixed paddle issue with Activision Casino ROM; the last card in game 4 can now be reached.
Added new pseudo-registers to the debugger, useful for conditional breakpoints (_fcount, _cclocks, _vsync, _vblank).
Added 'timing' commandline argument functionality to the UI, so you no longer need to use the commandline to set it.
Size restrictions on the TIA image are now strictly enforced. The maximum height of a 1x TIA image is now 256 lines.
Added a new setting to the 'fullres' option named 'auto'. Using 'auto' will let Stella decide the best videomode to use in fullscreen.
Changed 'gl_fsmax' option to mean 'scale TIA image in fullscreen'. It will have no effect on UI modes.
Changed 'gl_aspect' option to range 80-100 (previously, it was 50-100).
Removed 'ui_zoom' and 'tia_zoom' options, replacing them with 'tia_filter' (which can be zoom1x, zoom2x, etc). There is no equivalent for ui_zoom, since the UI can no longer be scaled.
Added experimental 64-bit version for Vista64 (may also work on WinXP64). This hasn't been extensively tested, and is probably quite a bit slower than the 32-bit version.
OSX port now requires at least 10.3 and XCode 3.0 to compile. Sorry, but I no longer have access to older systems to compile for 10.2.
Huge updates to the documentation, particularly concerning the debugger. Many features that have been in Stella for a while are now documented for the first time.
May 23, 2008
Stella release 2.6.1 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Introduced more accurate timing for NTSC vs. PAL modes, where the framerate is based on the number of scanlines per frame. This should eliminate 'clicking' sounds when emulating ROMs that don't follow the exact NTSC or PAL scanline specs.
Added ability to see the current number of scanlines and corresponding framerate to the TIA emulation. This can be set with the '-stats' commandline argument, or dynamically turned on and off with the 'Alt-l' key combo.
Modified '-framerate' commandline argument, where a non-zero value overrides the automatic framerate calculation (based on number of scanlines). Setting 'framerate' to zero re-enables auto-frame calculation. Also, re-enabled changing the framerate from within the UI.
Added '-timing' commandline argument, which sets the type of waiting between processing frames. Setting it to 'sleep' emulates the previous behaviour in Stella; setting it to 'busy' emulates z26, and can in some cases eliminate screen tearing (at the expense of using all available CPU time).
Fixed issue with debugger disassembly and mirrored $40 TIA write addresses. They were actually defined at $30, and generating incorrect labels.
Fixed issue in AtariVox and SaveKey controllers where accessing the EEPROM sometimes failed after the first write.
Changed AtariVox and SaveKey EEPROM emulation to default to $FF for a blank EEPROM.
Fixed regression in cart auto-detection logic; some F6 ROMs were being misdetected as E7.
Fixed issue with M6532/RIOT timer initialization; it was causing some ROMs to hang (most notably Summer Games). Related to this, reworked the built-in random number generator to generate 'more random' numbers.
Fixed bug in CommandMenu where console buttons (Select, Reset, etc) weren't doing anything.
May 16, 2008
Stella release 2.6 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Added AtariVox support using a real AtariVox device, where Stella sends data directly to the AtariVox. For now, this is supported in Linux/UNIX, OSX, and Win32 only. You'll obviously need a real AtariVox, and a serial<->USB adaptor to connect it to your system. Added '-avoxport' commandline argument used to set the serial port to which the AtariVox is connected. Special thanks to Al Yarusso and Richard H. for providing sample hardware.
Added AtariVox and SaveKey EEPROM emulation. This reads/writes data to a 32KB file, not to the actual hardware. Very useful for testing EEPROM support without actually wearing out the real device. Special thanks to J. Payson for providing the EEPROM emulation code, and A. Herbert for answering many driver-related questions.
Added support for CX-22, CX-80, and AmigaMouse trackball controllers.
Improved debugger symfile handling so that addresses accessed as read-only won't use write-only labels (and vice-versa). More work is still needed in this area.
Added M6532/RIOT tab to the debugger. This will be expanded on in a future release.
Added TIA emulation fixes for graphical glitches in Escape from the Mindmaster, Mission Survive, Solaris, and SWOOPS!
Fixed bug where fullscreen OpenGL scaling wasn't working on 4:3 monitors.
Further improvements to the M6532/RIOT emulation, which unfortunately have broken old state files (again).
Added deadzone setting, for adjusting the deadzone amount for analog joysticks. This can be set using the commandline argument '-joydeadzone' or dynamically within the UI.
Make ROM disassembly in debugger take advantage of a wide window.
Fixed bug in 6507 BCD handling introduced in the last release.
For the Win32 port; Win9x should be fully supported again.
April 9, 2008
Stella release 2.5.1 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Fixed M6532 RIOT timer emulation. More testing is needed, but the changes so far have fixed several ROMs that didn't work before.
Fixed issue with weird characters in the debugger disassembly when loading .lst files.
Fixed bug where entering the debugger for 4A50 and E0 carts caused the ROM to be frozen afterwords.
Removed logic whereby starting a ROM from something other than the built-in launcher wouldn't allow the user to go back to the ROM launcher.
Fixed bug (hopefully) with the app icon not showing on the Stella window. Further testing is needed, since I can't duplicate the error myself.
Fixed default snapshot folder issues; the folder will now be automatically created in the same place as state folders, ini files, etc (whereever that may be for your platform).
Re-added 'lastrom' functionality, where Stella will remember and auto-select the last ROM that was successfully launched in the ROM launcher.
For Stella developers, fixed SpeakJet emulation so it compiles again. No improvements have been made to the emulation itself, though.
March 28, 2008
Stella release 2.5 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Added RomInfo widget to the ROM launcher, which shows properties information and a snapshot of the currently selected ROM. Updated the UI and added '-romviewer' commandline argument to activate this setting. Note that the ROM launcher will have to be sized at least 640x480 for this to be used. Also note that the snapshots must be in 1x mode with a maximum size of 320x260. This will be expanded on in a future release.
Added ROM audit functionality, whereby ROMs can be physically renamed according to their properties' name.
Added bankswitching support for 0840, SB, X07 and 4A50. A special thanks to Eckhard Stolberg for much help in this area.
Removed "non-browse" functionality from the ROM launcher; it now always uses browse/filesystem mode. The previous 'pretty' names can now be seen by renaming all your ROMs with the new ROM audit feature.
Huge overhaul of controller handling and Stelladaptor support, making it much easier to add new controller types in a future release.
Fixed paddle issues in Night Driver; paddle emulation speed should be much better.
Fixed several 6507 emulation bugs related to BCD handling.
Updated ROM properties based on info from RomHunter.
ROM properties can now be edited from the ROM launcher; you no longer have to start a ROM to do so.
Added support for configurable font to ROM launcher (currently only 'small' and 'large'). Updated the UI and added -launcherfont' commandline argument to change this setting.
Added SECAM, NTSC50, PAL60 and SECAM60 to the list of formats that can be used. Also, switching between these modes with 'Ctrl-f' now switches the palette only; the number of scanlines won't change.
Fixed crash when switching between software and OpenGL mode with a Stelladaptor plugged in.
Added '-tiafloat' commandline argument, which determines whether or not the TIA pins are in a 'floating' state. This is useful for testing on certain CMOS EPROM chips where the unused TIA pins on a read are not floating but pulled high.
Fixed issue in debugger where once a .sym file was loaded, it was used in all ROMs loaded after that.
Fixed issue in debugger where equate names weren't showing up in the RAM and CPU widgets. Note that this still isn't perfect, and needs support from DASM for proper functionality.
Updated state file format, creating smaller files (and in preparation for state rewinding in a future release). Old state saves will no longer work.
Added '-bs' commandline argument, which is an alias for '-type' (which is still present).
Removed -pXspeed' commandline arguments, and replaced them with a single '-pspeed'.
Removed '-paddle' commandline argument. The paddle currently emulated by the mouse can still be changed with Ctrl-0..3 or within the UI, but the setting is no longer saved.
Reworked UI for specifying that the console ports have been swapped, hopefully making it easier to understand.
Added 'Ctrl-c' & 'Ctrl-v' to EditTextWidgets, allowing to copy and paste the text widget contents. More work in this area is coming in a future release.
Added 'Ctrl-leftarrow' and 'Ctrl-rightarrow' to EditTextWidgets, to move to the first character of previous and next words (respectively).
For the Win32 port: fixed OpenGL crashes in Vista. Graphical updates are still slower in Vista compared to XP, though.
For the Win32 port: default folder for Stella config files is now 'My Documents\Stella'; this can be disabled if necessary. This should fix issues with losing settings when launching Stella from an IDE, and the creation of stella.ini and 'state' directories in many different places.
For the Win32 port: several fixes to the Visual Studio project files, allowing building in debug or release mode, for both i386 and x86_64. The project files have been upgraded to Visual Studio 2008, and Stella can now be built and distributed without the VS runtime libraries.
Updated configure script for cross-compiling Win32 version in Linux.
September 18, 2007
Stella release 2.4.2 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available.
Made usage of 'GL_TEXTURE_RECTANGLE_ARB' extension configurable, and have it default to off. This should take care of the black/white screen many people were experiencing with ATI video hardware. This is accessible using the 'gl_texrect' commandline argument). Set it to 'true' or 'false' to enable/disable the extension.
August 27, 2007
Stella release 2.4.1 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Re-added OpenGL aspect ratio setting ('gl_aspect' commandline argument).
Re-added non-browser mode to the ROM launcher.
For the Linux/UNIX port; fixed OpenGL vsync issue with Nvidia video cards.
August 20, 2007
Stella release 2.4 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Added new video sub-system where fullscreen and windowed modes are treated differently. Windowed modes now use '-zoom_tia' and '-zoom_ui' arguments, while fullscreen modes can be specified by resolution using the new '-fullres' argument.
Widescreen video modes are now supported; Stella will simply center the image with surrounding black borders.
Many UI-related changes, including resizable ROM launcher and debugger windows, and a new UI palette (the previous 'classic' palette is still available). This is still a work in progress.
The locations of all major config files (statedir, palette file, cheat file, properties file, etc) are now configurable from the commandline and within the UI.
Updates to TIA palette support. Added SECAM support, and removed the built-in 'original' palette. Standard, z26, and user are still available.
Various bugfixes to some debugger commands. The 'run' command no longer causes a crash, and several others have better error-checking.
Added more complete cartridge auto-detection for Commavid (CV), 3E, 3F and Activision (FE) formats.
Removed XStart and Width ROM properties, since the forthcoming TIA rework won't be using them.
Reworked internal storage of ROM properties to be faster and take up less space.
Added several different ways of stretching the OpenGL image to the '-gl_fsmax' argument, for more flexibility.
Removed OpenGL aspect ratio setting favour of the previously mentioned video changes. We'll see how this goes.
Removed dirty-rect support from software rendering, since it was actually sub-optimal in Windows and OSX and defaulted to off in previous versions.
Added support for gzipped ROMs.
Re-added pause support.
Re-added support for Windows 98.
Removed support for 'STELLA_BASEDIR' environment variable, since each config file can be now configured separately.
Removed '-fastscbios' argument, since it must always be turned on.
Removed PSP support, since it hasn't been updated in over a year, and someone else is maintaining another port elsewhere.
For the Unix/Linux port; fixed 'make install' issues, and changed icon to PNG format.
January 17, 2007
Stella release 2.3.5 for Linux, Mac OSX, Windows and GP2X is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Greatly improved cartridge bankswitch type auto-detection. Stella can now (mostly) autodetect cartridge types 'E0', 'E7', '3E', '3F' and Superchip carts. Obviously, this autodetection is not infallible, but relies on patterns in the ROM data, and how it was compiled. Because of the auto-detection types already supported, almost all bankswitch info was removed from internal ROM properties. Set the ROM property "Cartridge.Type" to "Auto-detect" for this to take effect.
Added auto-detection of display type (NTSC or PAL). Currently, PAL60 ROMs will be detected as NTSC. This is almost 100% accurate, and fails in very few cases (for those that are mislabeled, the ROM properties can be set specifically). Set the ROM property "Display.Format" to "Auto-detect" for this to take effect.
Improved emulation timing when exiting one ROM and starting another. Previously, this could result in the second ROM having its sound start later than it should have.
Removed pause functionality from the core, since it's been superceded by the other event states. You can now enter one of the menus for a similar effect (options, command, debugger, etc).
Added toggle for PAL color-loss emulation, which defaults to off. Previous versions of Stella always used color-loss emulation. Related to this, added 'colorloss' commandline argument.
Added rudimentary support for configuring the UI palette ('uipalette' commandline argument) and ability to change the size of the launcher window ('launchersize' commandline argument). This will be expanded on in future releases.
Reworked options menu so it's now accessible from the ROM launcher as well as while playing a ROM.
Re-added ability to change the width and height of a Console. Related to this, changing XStart/YStart/Width/Height dynamically no longer resets the ROM.
Removed 'tiadefaults' commandline argument, since Stella will now default to using accurate positioning, and not use 'tweaks'.
Joystick code now allows all 4 directions; 'Bumper Bash' now works correctly.
Improved Keypad emulation; 'Alpha Beam with Ernie', 'Oscars Trash Race' and 'Magicard' now work correctly.
Reworked GUI code, so that all dialog boxes are automatically centered.
Added 'rominfo' commandline argument, which prints some detailed info for a ROM.
For the OSX port; fixed crashes in OpenGL mode.
For the GP2X port; some improvements to the sound code.
For the GP2X port; added vertical centering of the TIA image (when possible).
December 22, 2006
Stella release 2.3 for Linux, Mac OSX, Windows and GP2X is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Note: Because of the many changes in this release, all settings will be reset to defaults. If this doesn't happen for you, it will be necessary to manually delete your previous settings (see 'Settings' section of the manual for more information).
Potentially huge speedups in software rendering mode, both in emulation and UI modes. Deactivating 'dirty rects' uses these new modes, which can be 2-3 times faster for many configurations.
For UI navigation, changed from using 'joymouse' to the more familiar 'tabbing' functionality, where you move from object to object by use of some tab key. As a result, completely removed the 'joymouse' commandline argument and all associated functionality.
Added event remapping for UI events, separate from events while in emulation mode.
Added support for PAL60 ROMs, which use the PAL palette and resolution but run at NTSC timing (60Hz). Added ROM property for this, and updated the internal properties database for many PAL60 ROMs.
Added support for user-definable palettes. For now, only one extra palette is supported, but in the future we may have them specified per-ROM.
Fixed bug in PAL colour-loss emulation, which wasn't actually being done for the original Stella and z26 palettes.
Fixed several TIA-related emulation bugs as reported on AtariAge. More fixes will come with the TIA rewrite, due in the next release.
Added new scaler infrastructure, replacing the '-zoom' commandline argument with '-scale_ui' and '-scale_tia'. This means the UI and emulation can now be scaled independently.
Added '-gl_vsync' commandline argument and associated UI elements, which uses synchronization to vertical blank interrupt in OpenGL on supported systems. This eliminates tearing in OpenGL rendering.
Changed naming of snapshots and state files. These files are now named based on the names given in the properties database, and no longer use the 'md5sum' name. As a result, state files from previous versions will no longer work unless they're manually renamed. Related to this, removed the '-ssname' commandline argument.
Fixed bug where 'Snapshot saved' appeared when taking snapshots in succession.
Added a 'Previous directory' entry to the top of each listing while in ROM Browse mode, which is equivalent to the 'Go Up' button. This makes it easier to navigate the filesystem, since you never have to 'tab out' of the ROM listing.
Added all sound related commandline options to the UI, so you no longer have to use the commandline to set those options.
Added new property to ROM properties specifying whether to swap paddles plugged into a virtual port. This eliminates the need to manually set the paddle mode for those ROMs that don't use paddle zero by default.
Added a 'Defaults' button to the Game Properties dialog, which resets the ROM properties to the internal defaults, deleting that ROMs properties from the external properties file.
Fixed bug whereby modified ROM properties weren't being reloaded when restarting a ROM.
Made 'phosphor' and 'phosphor blend' a ROM property, meaning it can be set per-ROM.
Added support for relocating the base Stella directory, by setting the environment variable 'STELLA_BASEDIR'. This must be done each time before Stella starts.
Added '-fastscbios' commandline argument, which speeds up loading of vertical bars in Supercharger ROMs, and made it the default.
Added '-autoslot' commandline argument, which automatically switches to the next available slot after saving a state. This defaults to off, and must be set from the commandline.
Fixed bug in debugger command 'runto', which could enter an infinite loop under some conditions.
Updated configure/build toolchain so patching is no longer required for Debian packages.
Removed dependency on PNG library (PNG snapshots are still present, but the actual library is no longer required).
For the OSX port, improved OpenGL performance on Mac Mini using Intel GMA950 video hardware.
For the GP2X port, added support for PAL ROMs, and updated SDL to use hardware scaling.
April 7, 2006
Stella release 2.2 for Linux, Mac OSX, Windows, WinCE and GP2X is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Added new ROM browser option which works like a normal filesystem browser, allowing navigation throughout the filesystem. The old mode of browsing is still present, and can be toggled at runtime. Related to this, fixed bug whereby sorting in the ROM launcher sometimes didn't work.
Integrated stella.pro properties into the application, resulting in faster startup time. Now Stella can be redistributed as a single binary; no external files are needed, but they will still be used if present.
Reworked ROM properties files once again. The 'user.pro' file has been removed, and all user-defined properties are stored in 'stella.pro' instead. You should delete all properties files when upgrading to this version, to take advantage of the speed increases.
Reworked settings files once again. Removed all references to a global settings file. Each user now gets a user-specific settings file only. If that file doesn't exist, the built-in defaults are used.
Added 'conditional saving' of the cheatcode and settings files, so that these files are only written to disk when absolutely necessary. This doesn't really affect desktop systems, but is very useful for systems with flashram-based storage (GP2X, WinCE, etc).
Reworked Settings class, hopefully fixing a bug whereby settings weren't being saved in certain cases (most evident in the OSX port).
Added 'tiadefaults' commandline option, which can also be toggled from within the GUI. This option disables all TIA positioning 'tweaks' that typically make a game look better, and present the image exactly as it would appear on a real 2600.
Added jitter-detection code for the paddle emulation, which should eliminate an annoying 'jittering' effect when using paddles with a Stelladaptor.
Related to jitter-detection, added '-pthresh' commandline option and GUI entry, which sets a bound below which the emulation detects jitter.
Fixed crash when adding one-shot cheats.
Fixed bug in RAM comparitive searches in the debugger.
Fixed bug with setting snapshot naming type from the GUI (it was always being set to 'romname').
Re-added low compatibility CPU emulation mode, since it benefits some slower systems. This is activated with the commandline argument '-cpu low'.
For the OSX port, added Universal binary support.
For the OSX port, reworked the menu handling, so that certain menu options are only enabled when it makes sense to do so.
For the GP2X port, fixed joystick deadzone issues and scroll bug in ROM launcher.
For the GP2X port, fixed issue with PAL ROMs causing a crash because of screen size. A message is now shown indicating that PAL ROMs are not yet supported.
January 29, 2006
Stella release 2.1 for Linux, Mac OSX, Windows, WinCE and GP2X is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Added phosphor effect, similar to z26. Useful on ROMs which alternate sprites from one frame to another, resulting in an annoying flicker. When using phosphor mode, a pixels colour is mixed with its previous value, resulting in a blended image that doesn't flicker, emulating the phosphoresence effect on a real television.
Added 'pp' developer commandline argument to set the "Display.Phosphor" property, and 'ppblend' to set the amount to blend pixels in phosphor mode. Also added 'Alt p' key to enable/disable phosphor effect while ROM is emulated. By default, phosphor mode is only used when necessary, as specified in the stella.pro file.
Renamed 'cheetah' commandline argument to 'cheat'.
Added per-frame cheatcodes (4 characters long), which are evaluated each frame.
Added cheatcode GUI, where cheats can be named, edited, saved, etc.
Cheat codes are now saved to stella.cht file and are automatically reloaded when Stella starts.
Improved 'joymouse' functionality. While in GUI mode, any axis will simulate mouse movement, and any button will simulate a mouse click. So the GUI can be completely navigated without a mouse.
Improved CommandDialog and LauncherDialog wrt joymouse functionality. These dialogs are used more than any other on devices without a mouse, so joystick axis movement switches between GUI objects, rather than simulating the mouse. This leads to much faster selection of objects.
Added mapping of multiple SDL joystick axis to Event Mapping.
Added joystick hat support, and mapping of multiple hats to Event Mapping.
Added remapping of paddle emulation to the keyboard or joystick axis (the mouse is still used by default for paddles). Related to this, use more precise analog values when analog axis are mapped to analog-type events (such as paddles).
Treat joystick events as other types of controllers based on the virtual port entry in stella.pro. This means that mappings for a joystick will emulate other devices when necessary.
Added 'sp' developer commandline argument, which sets the "Console.SwapPorts" property and swaps the arrangement of the virtual ports. Useful for games like "Raiders of the Lost Ark", where the joysticks are normally swapped.
Added ability to set which Stelladaptor device emulates which virtual joystick port ('sa1' and 'sa2' commandline arguments, which accept 'left' or 'right').
Fixed issues with jittering joysticks/mice causing weird events when starting Stella.
Added 'freq', 'tiafreq' and 'clipvol' commandline arguments, which affect the sound subsystem (see manual for further info).
Made state files completely cross-platform, both in terms of endianness as well as CPU size (32 vs. 64 bit).
Fixed crash with using 'cheat' and 'break' from the commandline.
Implemented dynamic loading of OpenGL library.
October 25, 2005
Stella release 2.0.1 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Added 'dirtyrects' support, which speeds up rendering for some Windows users.
Fixed bug where taking snapshots would fail if the snapshot directory wasn't specified.
Made ROM launcher case-insensitive, so upper and lowercase names are now mixed in the correct order.
Fixed ZIP ROM support to search the archive for ROMs ending with either .bin or .a26 (case insensitive).
ROMs which don't have an associated properties entry are no longer named 'Untitled' in the Stella window or when taking snapshots. The actual ROM name is now used.
Changed minimum height of debugger to be 27 lines in the prompt, or approx. 700 pixels high. This should make using the debugger easier for users with lower resolution monitors. Related to this, the RomWidget now uses all possible vertical space when changing the debugger height.
Fixed bug related to upgrading Stella and event mappings being incorrect. Stella now detects this, and uses the default mappings. So upgrading to version 2.0.1 means your event mappings will be reset.
Fixed bug in loading debugger symbol files generated on different operating systems.
For the Windows port; added exe installer based on InnoSetup.
For the Windows port; compiled icon into Stella, so it now looks like a real Win32 application.
For the OSX port, reverted window resize key combos back to 'Cmd =' and 'Cmd -' to match the 1.4.2 release.
October 16, 2005
Stella release 2.0 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Added integrated GUI. Stella is now a fully graphical application, and all settings can be changed dynamically while the application is running. That means the commandline is no longer required (but support is still there for those who want to use it).
Added ROM launcher. You can now exit a game and start playing another one from directly within Stella (you no longer have to quit Stella and restart it).
Because of the integrated GUI and ROM launcher, StellaX and KStella (the Windows and Linux frontends) have been discontinued. The OSX port now uses the launcher as well.
Added an integrated debugger for game developers. This is currently the first version of a debugger in Stella, but it's already quite usable.
Added new sound subsystem, which is much faster and more accurate. Related to this, added stereo sound output (used by some homebrew games).
Added ZIP support. Stella can now open ROM's compressed in zip format.
Added cartridge 'frying', thanks to Fred "batari" Quimby. This emulates the action of turning the power button on and off on a real Atari, often resulting in some strange effects.
Added ability to edit current ROM properties from directly within Stella, which can then be saved directly into the 'user.pro' file. So creating a properties entry for a new ROM can be done without any external tools.
Added initial support for using Stella in an 'arcade-box' environment without a keyboard. This consists of an in-game menu for choosing common actions in Stella, as well as using the joystick navigate the mouse pointer.
Reworked properties system to use both a system-wide 'stella.pro' and a per-user 'user.pro' properties files. Changes made by the user and stored in 'user.pro' are no longer erased when upgrading Stella.
Added support for cartridges with 3E bankswitching format.
Added preliminary Cheat support.
Added Alt/Shift-Cmd z, x, c, v, b, n keys to enable/disable the P0, P1, M0, M1, BL, PL bits in the TIA, respectively.
Added Alt/Shift-Cmd . key to disable all bits in the TIA.
Added Alt/Shift-Cmd / key to enable all bits in the TIA.
Added Alt/Shift-Cmd g key to switch dynamically switch between software and OpenGL modes while Stella is running.
Added Ctrl/Cmd r key to reload the ROM currently being emulated.
Added Alt/Shift-Cmd s key to merge the current game properties into the properties file.
Added help commandline argument. Launching Stella from the commandline with no options now starts Stella in ROM launcher mode, instead of showing help (as in previous versions).
Added the following commandline arguments for developers: pro, type, ld, rd, tv, lc, rc, bc, format, xstart, ystart, width height, cpu, hmove. Developers can consult the manual for further details.
Removed mergeprops commandline argument, since there are now dedicated keys to either save or merge game properties.
Removed hidecursor commandline argument. Stella will now automatically decide when to use this setting.
Fixed framerate when switching between NTSC and PAL modes. Stella now uses the correct framerate based on the format of the ROM, in terms of both video and audio.
Added 'configure' support to the build process for both Linux and Win32 (using MinGW). Developers can now use the familiar 'configure; make; make install' commands to compile Stella.
Further consolidation and integration of SDL. This should lead to faster operation and a more consistent look for all ports.
Fixed some 64-bit issues. Stella now compiles and runs correctly on AMD64 and PPC64 Linux systems.
Updated the Stella manual with pictures of the new integrated GUI.
February 19, 2005
Stella release 1.4.2 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Updated the sound system. All popping and cracking sounds that previously occurred at program start/stop and when entering/exiting menu or pause mode have been eliminated.
Fixed the gl_fsmax argument to mean "switch to desktop resolution on fullscreen OpenGL", instead of to the maximum possible resolution (the two are not always the same).
Added Alt [ and Alt ] keys to dynamically adjust the sound volume during emulation.
Added Control 0, Control 1, Control 2, Control 3 keys to dynamically change which paddle the mouse should emulate.
Added video_driver argument. This accepts the different options that can be specified for SDL_VIDEODRIVER (see SDL homepage for more information). Basically, it eliminates the need to set the SDL_VIDEODRIVER environment variable.
Made sure screen is refreshed before taking a snapshot. This eliminates the problem with new snapshots containing the text "Snapshot saved".
For the Windows port; added windib and directx as options for 'video_driver' when using software rendering. The 'windib' option is now the default, and in many cases it's up to 10 times faster than using 'directx'.
For the OSX port; added 'Cmd-R' key to reload the currently loaded ROM.
August 15, 2004
Stella release 1.4.1 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Fixed PAL sound issues. PAL games now should sound correct (no distortion or missing sounds), but some games may still run too fast. This is still a work-in-progress, and will be fixed in Stella 1.5.
Cleaned up the SDL event gathering loop. This should hopefully fix the problems with "double-pumping events" reported by some Windows users. Event gathering and dispatching is now much faster as well.
Fixed a bug where the Control or Alt keys could be assigned to some event, but they could never be used. Control/Alt can now be used for any event.
Updated stella.pro file to work with the latest Good2600 ROMset release (Thanks go to Voch for helping to maintain the stella.pro file).
For the Windows port; removed requirement for ROM files to be named *.bin in the StellaX frontend. The ROM's can now have any name, but ZIP-files are not yet supported.
For the Windows port; fixed the problems with the included modified SDL library and Windows 98 users. Stella should now run in Windows 98.
For the OSX port; added preference to allow user to select the directory in which ROM images are stored. This sets the default directory to start the browsing for a ROM in, and doesn't preclude the user from selecting a file outside that directory.
For the OSX port; fixed preferences bug where Preferences changed before a game was opened were not being saved.
July 17, 2004
Stella release 1.4 for Linux, Mac OSX and Windows is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Codebase ported to SDL. The DOS and X11 ports have been discontinued.
Sound code ported to SDL. For the Linux versions, ALSA and OSS sound support has been discontinued.
The Linux, MacOSX and Windows ports are now based on the same codebase and are actively maintained. That means simultaneous (and hopefully more frequent) releases.
A new Windows port has been created, with the GUI based on StellaX. This is the first new release for Windows since Stella 1.2. (software mode is not yet optimized; OpenGL mode works much better)
A new Mac OSX port has been created by Mark Grebe. This is the first new release for Mac OSX since Stella 1.2.
Added OpenGL rendering support.
Added more refined in-game GUI.
Added event remapping. Emulation keys can now be remapped to the keyboard or up to 4 joysticks.
Added native Stelladaptor support. Joysticks, paddles, and driving controllers have been tested.
Digital sound support (used in games like Quadrun and Pitfall2) has been greatly improved. Sound generation is now more tightly synchronized with video updates.
Added support for switchable palettes. Currently you can switch between the current Stella palette, original Stella palette (pre-1.2 versions), and the z26 palette.
Added support for UA Limited style bankswitching (Funky Fish and Pleiades).
Switched to using high compatibility M6502 mode by default. This means old state saves from previous Stella versions will no longer work.
The meaning of the "-sound" command line option has been changed. This option now accepts either 'true' or 'false (1 or 0) to enable/disable sound.
Changed sound mixer functionality. The system volume/mixer settings will never be changed; volume changes in Stella will only affect the emulation itself.
Added "-video" command line option. This option accepts either 'soft' or 'gl', to use software/OpenGL rendering.
Added "-gl_filter" command line option. This option accepts either 'nearest' or 'linear', to use GL_NEAREST or GL_LINEAR filtering.
Added "-gl_aspect" command line option. This option accepts a decimal value specifying how much to scale the width of the emulation image (useful for giving an authentic 'square-looking' 4:3 mode).
Added "-gl_fsmax" command line option. This option accepts either 'true' or 'false, and specifies to use the maximum possible resolution when in fullscreen OpenGL mode (useful for Linux and for Windows on laptops).
Added "-fragsize" command line option. This option accepts the size to use for sound fragments. Linux/MacOSX works well with 512, Windows seems to need 2048. This value must be a power of two.
Modified "-volume" command line option. If you specify '-1', Stella will use the system volume.
Renamed the "-pro" command line option to "-altpro".
Renamed the "-fps" command line option to "-framerate".
Removed the "-center" command line option. Stella now automatically centers the window when possible.
Removed the "-paddle real" command line option, since it never really worked correctly (and Stelladaptor support adds that functionality anyway).
Removed all command line options relating to the X11 port (owncmap, display).
February 17, 2003
Stella release 1.3 for DOS, Linux, and Unix is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Improved TIA sound system so that games with digitized audio work
Added saving and loading of game state to the core; X11, SDL, and DOS versions current support saving and loading game state
Added support for F4 bankswitching method
Pitfall II DPC sound emulation completed
Fixed a bug which caused the difficulty switches to operate backwards
Changed DPC auto-detection to use file size so that Pitfall II mods work
Modified RIOT timer emulation so that startup values are random
Added 3F bankswitching auto-detection routine so that homebrews and demos work without a stella.pro entry
Updated the TIA message boxes so they look a little nicer
Latest stella.pro file included in distribution
Added some developer options to the core, and the ability to change game width, height, xstart, ystart, and others while the emulation is running. Added ability to switch between NTSC and PAL at runtime, and the ability to save the current properties to a file or to merge the changes into the stella.pro file; X11 and SDL versions supported for now (compile option)
External sound server for the X11 and SDL versions no longer required, as all sound code is now integrated into the core
Changed locations of the user's config files for the X11 and SDL versions; the user's stellarc file is now located in $HOME/.stella/stellarc, state files are located in $HOME/.stella/state/ and the stella.pro file is located in $HOME/.stella/stella.pro
Changed the way options are supplied on the commandline for the X11 and SDL versions. Now all commandline options take exactly the same arguments as in the INI file.
Added "-accurate" command line option to choose between accurate (CPU-intensive) timing or less accurate (CPU-friendly) timing to X11 and SDL versions. This is the final version of what was considered experimental timing code in Stella 1.2.
Added "-sound" command line option to choose which sound backend to use (alsa, oss, sdl) with the X11 and SDL versions.
Added the developer command line options to the X11 and SDL versions, which are only activated in developer builds: -Dformat, -Dwidth, -Dheight, -Dxstart, -Dystart, -Dmerge
Fixed window resize bug in the X11 port
Added "-nosound" command line option to the DOS port to disable audio
DOS port supports a "-vsync" option to synchronize emulation with the video blank of the video card
Changed VGA code in the DOS port to use a 60Hz 320x200 and a 60Hz 320x240 graphics mode
DOS port has been updated to run better under Windows NT, 2000, and XP. There are still issues with the sound, however, it is usable.
DOS port is using a new Sound Blaster driver created by Matt Conte which supports auto-detection of sound cards.
DOS port supports a STELLA_HOME environment variable that defines the location of config files.
In the DOS port the stella.pro file is searched for first in the current working director and then in the $STELLA_HOME directory
In the DOS port the ROM image is searched for first using the specified path, then in $STELLA_HOME/ROMS, and finally in $STELLA_HOME
April 28, 2002
Stella release 1.2.1 for DOS is now available for download. This release fixes the following:
The control keys are no longer confused for the pause key
Bug in the pause key feature which caused the emulator to lockup on some systems has been fixed
April 24, 2002
April 23, 2002
Stella release 1.2 for DOS, Linux, and Unix is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Improved illegal CPU instruction support. Thrust and Qb will now operate correctly.
Improved emulation of undefined TIA reads. The ball in Video Pinball finally bounces off of the paddles!
More accurate NTSC and PAL palettes. These palettes should be much more like the colors displayed on a real TV.
PAL color loss is now emulated. If a PAL game displays an odd number of scanlines then the next frame will be displayed in black & white.
TIA emulation improved to fix some problems with Pole Position, Fatal Run, Dolphin, Decathlon, Robot Tank, and Hole Hunter.
Support for Pitfall II has been added, however, the enhanced sound provided by the DPC chip found in the Pitfall II cartridge isn't currently emulated.
Support added for the Commavid (CV) bankswitching method.
Support added for the Megaboy cartridge.
Improved Supercharger emulation including a new BIOS that shows the vertical blue progress bars like the real thing.
Code for the emulation core has been updated to work with newer C++ compilers compliant with the C++ standard.
Basic message support added to the TIA emulation. This allows a short message to overlay the TIA frame. Currently, it's used when switching color modes and difficulty settings.
The internal data structure for the stella.pro file was changed from a resizable array to a binary search tree. This results in quicker startup times.
An SDL port of Stella is available (requires SDL 1.2.0 or greater)
Added option to not load in the whole stella.pro file when starting Stella. This option is enabled on the X11, SDL, and DOS versions. Win32 version is left alone since it's needed for loading multiple games from the UI. Saves on memory usage.
Added INI file option to the X11 and SDL versions. Options can be specified in this file instead of entering them on the commandline. Any options entered on the commandline override options in the INI file. File is called stellarc. For the X11 and SDL versions, it can be in either $HOME (as $HOME/.stellarc) or in /etc (as /etc/stellarc). The one in $HOME has higher priority than the one in /etc.
Added snapshot support to the X11 and SDL versions. Pressing F12 saves the current screen in PNG format. Requires PNG library.
Removed stella.pro file from the binary, resulting in large space savings. The stella.pro file is no longer optional. For the X11 and SDL versions, it can be in either $HOME (as $HOME/.stella.pro) or in /etc (as /etc/stella.pro). The one in $HOME has higher priority than the one in /etc. For DOS and Win32 versions, the stella.pro file must be in the same directory as the executable.
Added pause functionality to the core. Implemented in DOS, X11, and SDL versions for now.
August 26, 2001
June 10, 2001
John Stiles' port of Stella 1.1.2 to the PowerMac is now available online in the download section. The biggest change is native support for Mac OS X.
November 3, 2000
Darrell Spice Jr.'s port of Release 1.1 of Stella to OS/2 is available for downloading.
Improved throttle routines for faster systems
Added PAL color palette and frame rates
New game controller status (which controller needed for current cartridge)
Keyboard controls are now user definable
Keyboard controls have changed
And much more...
August 22, 2000
Erik "Voch" Kovach's latest stella.pro file is online in the download section.
May 8, 2000
Release 1.1.3a of StellaX for Windows is available for downloading:
Fixed joystick handling regression
Fixed repaint problem on doc page
Fixed problem where some machines would report path not found
Added force 640x480 video mode
Added browse button on config dialog
Improved video detection logic
Added DisableJoystick options to stella.ini file
Rewrote the sound driver code - no more scratchy sound!
Added multiple screen shot support - first writes to stella00.bmp then stella01.bmp, etc.
Added cool round buttons on main screen
Added configuration dialog
Major code cleanup and performance tuning
Internal ROM list should be complete - make sure your roms are in the ROMS directory and that each rom has the ".bin" extension
Run on Windows 95, Windows 98, Windows NT and Windows 2000
September 29, 1999
John Stiles' port of Stella 1.1 to the PowerMac is online in the download section.
July 20, 1999
Joe D'Andrea's port of Stella 1.1 to IRIX version 6.5 is online in the download section.
June 11, 1999
Release 1.1.2 of StellaX for Windows is available for downloading:
Run on Windows 95, Windows 98, Windows NT and Windows 2000
Does not take over the .bin extension
DirectSound works on all systems
Added DirectInput support for keyboard, mouse, and joystick (except on NT)
Fixed minimize button bug
Created virtual list view to speed load time
Add screen capture (F12 key) to save current screen to a bmp file
Stella icon properly shows on the task list
March 20, 1999
Release 1.1.1 of StellaX for Windows is available for downloading:
Video works on all systems: Windows 9x, Windows NT and Windows 2000
Runs on systems without sound cards
Fixed some GDI leaks which would eventually cause a reboot on Win9x machines
Made GUI come up faster after a game is finished playing
Right player ';' key wasn't working in 1.1
Undocumented command line option: -mute (mute all sound)
Undocumented command line option: -showfps (show FPS at end of game)
March 18, 1999
Jeff Miller's port of Stella release 1.1 to Windows (StellaX) is available for downloading.
February 27, 1999
Stella release 1.1 for DOS, Linux, and Unix is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
DOS and Linux versions support real Atari 2600 paddles using a special PC game port adaptor
Linux version uses the new 1.2.x Linux Joystick API
Unix versions support the "-display" command line option for specifying the display to use
Unix versions support the "-owncmap" command line option to install a private colormap
Greatly improved Supercharger single-load and multi-load game support
Improved TIA emulation to support the RESPx multi-sprite trick
February 27, 1999
After some careful consideration I've decided to move the Stella web site. The new home page for Stella can be found at . This URL will redirect you to the current location of the Stella web site which is my school account for now.
David McEwen's port of Stella 1.0 to the Acorn platform and Joe D'Andrea's port of Stella 1.0 for IRIX 6.2 and Solaris 2.5.1 are available for downloading.
David Asbell's port of Stella 0.7 to Java is available for downloading in the 0.7 download directory.
October 7, 1998
Stella release 1.0 for DOS, Linux, and Unix is now available. Ports to other operating systems will be released as they become available. A partial list of features is:
Supports Robot Tank and Decathlon
Supports Joystick, Keyboard, Booster Grip, and Indy 500 Driving controllers
DOS version supports 320x200 and 320x240 graphics modes
Preliminary support for Chris Wilkson's Megacart bank-switching scheme
Improved graphics emulation (TIA)
Improved timer emulation (6532 PIA)
Improved CPU emulation (6502)
Improved Supercharger support
Contains properties for over 540 ROMs
Will soon be ported to to pretty much every OS under the sun :-)
August 2, 1998
Stella 1.0 Beta 1 for DOS is available in the "Development versions" download area.
July 25, 1998
At long last, Stella 1.0 Beta 1 is now available for Linux and Unix. This is a stable beta release and assuming no major bugs are discovered a final 1.0 release will be made in a few weeks. The beta release can be found in the "Development versions" download area. Ports to other operating systems will be released as they become available. A partial list of features is:
Improved graphics emulation (TIA)
Improved timer emulation (6532 PIA)
Improved CPU emulation (6502)
Improved Supercharger support
Supports Robot Tank and Decathlon
Supports Joystick, Keyboard, Booster Grip, and Indy 500 Driving controllers
Contains properties for over 540 ROMs
Will soon be ported to to pretty much every OS under the sun :-)
May 3, 1998
As far as the status of the next release of Stella progress is being made, however, it'll probably be another month or so before a final release is made. I hope you can wait...
April 13, 1998
Joe D'Andrea's port of Stella to IRIX version 6.2 is online in the download section.
March 27, 1998
Erik "Voch" Kovach's latest stella.vcs file is online in the download section. This version contains a few new settings for Color Bar Generator, Advertisement Cartridge, Night Stalker, and Seesaw.
March 13, 1998
Erik "Voch" Kovach's latest stella.vcs file is online in the download section. This version contains a few new settings and has a few tweaks here and there.
February 11, 1998
A once a year International Atari Collector/User Show set for the Summer of 1998 at the Disneyland Hotel in Anaheim, California is being planned. For more information see the Atari World 98 home page.
February 6, 1998
Erik "Voch" Kovach's latest stella.vcs file is online in the download section. This version contains settings for some of the newer games and has a few settings tweaked here and there.
January 12, 1998
Another improved stella.vcs file by Erik "Voch" Kovach containing the names of 479 cartridges is available from the download section.
January 8, 1998
An improved stella.vcs file by Erik "Voch" Kovach is available from the download section.
January 6, 1998
"Game Menu" version 3.2 by Jim Pragit is available from the download section.
December 21, 1997
Development of version 0.8 of Stella is proceeding slower than expected. A release before Christmas will not be made. Actually, a 0.8 release of Stella may never be made, instead the plan is for 1.0 to be the next release. Hopefully, the wait will be well worth it.
Have a Merry Christmas!
December 6, 1997
Stella has won an Archaic Ruins Editor's Choice Award
November 29, 1997
"Game Menu" version 3.1 by Jim Pragit is available from the download section.
November 12, 1997
"Game Menu" version 3.0 by Jim Pragit is available from the download section.
October 1, 1997
Stella was featured in the article "Great Games Never Die..." on page 84 of the October issue of PC-Gamer.
September 6, 1997
"Game Menu" version 2.1 by Jim Pragit is available from the download section.
August 29, 1997
"Game Menu" version 2.0 by Jim Pragit is available from the download section.
August 20, 1997
The development team is working on version 0.8 of Stella. A partial list of features is:
Optimizations to improve speed
Improved TIA and PIA emulation
Improved Supercharger support
Support for other controllers (Keypad, etc.)
And much more...
There is no estimated-time-of-arrival, however, hopefully it'll be ready by Christmas.
July 29, 1997
Stella version 0.7 has been released for Windows 95 & NT.
June 28, 1997
"Game Menu" version 1.61 by Jim Pragit has been released. It's available from the download section.
June 13, 1997
Stella version 0.7 has been released for the Power Mac and OS/2.
June 7, 1997
Stella version 0.7 has been released for DOS, Linux and Unix/X. Ports to other systems will be released as they become available.
June 2, 1997
Keith Wilkins is no longer supporting the DOS port of Stella due to lack of free time and other responsibilities. Bradford Mott will be maintaining the DOS port of Stella.
May 23, 1997
Most of the "core" code modifications for version 0.7 have been completed. Porting to the various operating systems is underway. Hopefully, a release will be ready around the end of May or beginning of June.
May 9, 1997
"Game Menu" version 1.4 by Jim Pragit has been released. It's available from the download section.
March 25, 1997
Development of version 0.7 of Stella is proceeding slower than expected, however, the wait will be well worth it. A partial list of new features is:
Optimizations making this the fastest version ever!
VCS files combined into a single file
ROM image filename independence (name them whatever you like)
Improved TIA emulation (Warlords works...)
Starpath Supercharger support
And much more...
There is no firm estimated-time-of-arrival, however, hopefully it'll be ready by the end of May.
March 17, 1997
"Game Menu" version 1.3 by Jim Pragit has been released. It's available from the download section.
February 17, 1997
Stella version 0.61 for Windows 95 & NT has been released!
February 14, 1997
"Game Menu" version 1.2 by Jim Pragit has been released. It's available from the download section.
February 10, 1997
The development team is working on version 0.7 of Stella. A partial list of new features is:
Optimizations making this the fastest version of Stella ever!
VCS files combined into a single file
ROM image filename independence (name them whatever you like)
Improved TIA emulation
And much more....
There is no firm estimated-time-of-arrival but it'll probably be the first or second week of April 1997.
February 9, 1997
Luc Miron has released version 0.2 of his utility which allows you to store all your VCS file data in a single file. It's available from the download section.
February 5, 1997
Stella version 0.6 released!
January 31, 1997
Jim Pragit has released version 1.1 of his front end for MS-DOS called "Game Menu". It's available from the download section.
January 22, 1997
Jim Pragit has written an excellent front end for MS-DOS called "Game Menu". It's available from the download section.
January 17, 1997
The "core" code modifications for version 0.6 have been completed. Porting to the various operating systems is underway. A release will hopefully be ready within the next week.
December 16, 1996
The development team is working on Version 0.6 of Stella. A partial list of new features is:
Faster than Version 0.5 on most games
Improved 6532 (PIA) emulation to fix those screen jitters
Support for almost all bank-switching methods
Improved TIA emulation
Better sound support for MS-DOS systems
Much smaller executable size
And much more....
There is no firm estimated-time-of-arrival but it'll probably be the third or forth week of January 1997.
November 16, 1996
Stella version 0.5 released!
October 31, 1996
The "core" code modifications for version 0.5 have been completed. Porting to the various operating systems is underway. A release will hopefully be ready by the 2nd week of November.
September 24, 1996
The development team is currently working on Stella Version 0.5. This version will have the following features:
Faster than Version 0.4 on most games
Sound support (hopefully)
More bank switching methods supported
Improved 6532 (PIA) emulation to fix screen jitters (Frogger works)
Fixed TIA undefined read accesses (Haunted House works)
This is a partial list of features since Version 0.5 is still in development. There is no firm estimated-time-of-arrival but it'll probably be sometime near the end of October or beginning of November.
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