Difference between revisions of "Nintendo Entertainment System emulators"
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The Nintendo Entertainment System (NES) is an 8-bit, third-generation console released on July 15, 1983 in Japan, where it was known as the Family Computer or Famicom, and on October 18, 1985, it released in the US. It retailed for $179.99. It had a Ricoh 2A03 CPU at 1.79 MHz with 2KB of RAM.
The earliest games released on the Famicom suffered from significant hardware constraints due to the way the Famicom was designed: limited memory addressing (which meant games had a low maximum ROM size), how the graphics are loaded onscreen, just the native sound processing is available, no saving... To solve this problem, Nintendo came up with two solutions:
- The Family Computer Disk System (FDS), a Japan-only add-on which played games from a semi-custom variant of Mitsumi's Quick Disk format. It offered slightly higher data storage and slightly enhanced sound processing. It also had a microphone never found anywhere else. There were plans to release it in the US, however since the NES itself had its launch delayed to late 1985, and the mapper solution obsoleted it, the add-on was never exported and some of its exclusives were ported as regular cartridge releases.
- Memory Management Controllers (MMC), also known colloquially as mappers. They solved every single problem above with bank switching for much more data, onboard FM audio chips, and much more. Most games released after 1986 that really pushed the system to its limits used mappers. A similar solution was used for the Game Boy.
Emulation for the NES is robust, with many high-quality emulators for various systems.
|PC / x86|
|Nintendulator||0.985 Beta git||✗||✗||Cycle||✓||✓||✗|
|FinalBurn Neo||WIP builds||✓||✓||High||✗||✓||✗|
|Mobile / ARM|
(based on fceux 2020.05.03 git)
0.4 r313 (GP2X)
|nesemu||0.2.3 Beta Preview
|FCE Ultra GX||3.5.2||✓||✗||Mid||✓||✓||✓|
|NesterJ[N 3]||1.13 beta 2
|FCEUltra for PS2||0.9.3
|VirtuaNES for 3DS||git||✓||✗||Mid||✓||✗||✗|
- The CPU is instruction-cycle accurate, but not sub-instruction cycle accurate (TODO ). While this inaccuracy doesn’t affect most games, there are some that that rely on sub-instruction level timings.
- Only available as a libretro core (e.g. RetroArch).
- AoEX is based on NesterJ 1.12 Plus 0.61 RM, so it includes features like rewind, cheat code support, rotated/mirrored screen, sepia palette, support for rare mappers (the pirate bootleg FF7 works on it), etc. Its compatibility is inferior to 1.13 beta 2.
- Mesen is the most accurate NES emulator according to currently established NES test ROM suites. It should be the emulator of choice for those who desire the utmost accuracy. Mesen is also very user-friendly and supports a lot of features that other emulators are missing such as; HD packs, netplay, auto-updating, good built-in filters, both .zip and goodmerged file loading, etc. The standalone emulator has ceased development for unknown reasons, but the libretro fork and NovaSquirrel's fork is still active.
- puNES is the second most accurate NES/FDS emulator according to a separate test battery run by the TASVideos community.
- Nestopia also has a high ranking in those same tests. Even so, Nestopia has issues with The Young Indiana Jones Chronicles and doesn't display the status bar in Mickey's Safari in Letterland correctly (among other problems). Nestopia Undead Edition is a fork of Nestopia meant to keep it alive and fix the aforementioned bugs. This version is generally recommended over vanilla. Even the libretro core for Nestopia is in the Undead Edition.
- Nintendulator and My Nes also have a fairly high ranking in those tests.. NintendulatorNRS is a fork of Nintendulator which has support for the Famicom Disk System, rare mappers, and many unlicensed and bootleg carts and systems.
- FCEUX scores rather low in these tests, despite being a recommended emulator on TAS Videos. The New PPU is more accurate than the Old PPU, thankfully. The emulator is still useful, though, thanks to its robust Lua scripting and incorporating FCEUmm into its feature set.
- VirtuaNES also scores quite low in the tests, but in turn supports several obscure peripherals that are not available on other emulators.
- For official emulation, there is Nintendo's own Virtual Console or Nintendo Switch Online. The Wii has a significantly larger library of NES games to choose from than the 3DS or Wii U, especially from third-party publishers.
There are many other NES emulators not listed here, as the NES has more emulators than any other system (new ones are started all the time). Only those that are well known or stand out in some way are covered here.
A key difference between many emulators nowadays is how many mappers they support.
- No mapper: Supported on every emulator even official Nintendo emulators.
- Official mappers (UNROM, AOROM, MMC1-6): Most emulators, as well as Nintendo's Virtual Console (but not their GBA emulators), will cover these.
- Third party mappers (Various: e.g. Konami's VRC6/VRC7) While officially licensed by Nintendo, they were not allowed outside Japan. As a result, for their Western releases, many games that took advantage of their features (advanced ROM mapping, extra sound channels) were reprogrammed significantly and shipped on the official mappers, often with simplified soundtracks. A lot of fan emulators worth their salt will cover these. With those, you cover the entire officially licensed library.
- Unlicensed mappers: Mostly used by pirate cartridges, often long past the console's official commercial lifespan. Only the more accurate emulators (Mesen-X, puNES, NintendulatorNRS, Nestopia UE) will even bother covering them in a whack-a-mole quest for every new one discovered to this very day. If you're not interested in unlicensed Chinese or Russian bootlegs or newer unofficial NES demakes, it isn't a problem.
The NES ROM information isn't sufficient to describe the cartridge and emulate it, so emulators have to include the layout and behavior of these mappers in their code, while the ROM header tells the emulator which mapper to choose. So unlike with other consoles, no matter how accurate a given NES emulator will get, it will still never be able to run newly discovered ROM dumps from cartridges that used a so-far unknown mapper. Thus, Unlicensed NES support will be inevitably incomplete and a constant work-in-progress, hence claims some emulators are "inaccurate".
Related to this issue: This is why most emulators won't run unheadered NES ROMs. Newer versions of Nestopia can open those, but they're handled in a slightly different way: the information that would have been included in the iNES header is instead provided in emulator configuration files that get summoned as long as the ROM's hash matches exactly the No-Intro dump of that given game (which is inconvenient for romhacks).
QD FDS support
Games dumped off the Famicom Disc System come into two major types:
- .fds format: Most common format. Ubiquitous in ROM sets (GoodSets, No-Intro). Omits some checksum data.
- .qd format (stands for QuickDisk): Only ever used in official Nintendo re-releases. Almost identical to fds, but a full dump with checksum data. May omit padding.
The checksum data in question would be checked at BIOS startup to verify the integrity of the image and whether it was tampered with, in which case it will throw an anti-piracy error. As of now, no NES emulators support the alternate more complete dumps, as well as fudging that check's result to always return a negative. To emulate a .qd image, stripping the checksum data with a custom script is needed.
- Main article: Overscan
Several NES games need their overscan to be cropped to look proper. Unfortunately, there is no standard level of overcropping. Many games require different levels for best results. For example, Super Mario Bros. 3 requires quite a bit of cropping, however, the same level of cropping will obscure the letters of the status bar in Castlevania games.
- Main article: Famicom color palette
Unlike consoles such as the SNES, which natively generate their image in pure RGB, the Famicom normally generates and outputs an encoded NTSC video signal. This must then be decoded by the TV's built-in NTSC decoder, which means the resulting color palette often varies depending on the display's decoder. For this reason, NES games will appear to have different colors on different TV sets. To properly emulate this part of the NES experience, many Famicom emulators have a variety of different palettes to choose from.
The 3DS and Wii U versions of Virtual Console use extremely dark color palettes. This is apparently not an accuracy issue, but rather an anti-epilepsy measure. For the Nintendo Switch Online service, the games were directly edited to remove seizure-inducing patterns, allowing it to use a normal palette.
There were many accessories released for the NES but Emulation General only covers accessories that are truly differentiated data streams from the basic controller. For example, the Power Glove is in actuality just a really complicated NES controller, designed to convert motion into D-PAD, SELECT, START, A, and B button commands. The same goes for R.O.B. and his Stack-up and Gyromite games because he was really just the second player. Strangely, the Famicom has a lot more peripheral hardware to emulate than the NES.
|Zapper||An electronic light gun accessory that allowing players to aim at the display and shoot various objects that appear on the screen.||Duck Hunt
|Various||Emulated in the form of a mouse click (PC), tap (for mobile), remote (Wii ports of NES emulators), or faked pointers using a controller.|
|Arkanoid/Vaus Controller||A specific game controller with one button to "fire" and a dial to control back and forth movement.||Arkanoid
Arkanoid: Revenge of Doh
Family Fun Fitness
|A game controller that allows players stepping on a gray floor mat with 12 pressure-sensors embedded between flexible plastic to control gameplay.||Stadium Events
|NES Four Score
|A multitap accessory that allows players to enable up to 4-player gameplay using infrared wireless communication.||R.C. Pro-Am II
Bomberman II[N 1]
Nintendo World Cup
A Nightmare on Elm Street
|Various||Emulated by having an option to switch between 2-player and 4-player mode or just enabling/disabling Player 3 and Player 4's controller.|
|Family Computer Disk System||See above||Legend of Zelda: The Hyrule Fantasy
Zelda II: The Adventure of Link
Light Mythology: Palutena's Mirror
|Various||BIOS file (which can be found here) is required for FDS emulation. Note that there's two versions of the BIOS: the one that comes with FDS and another one that comes with Sharp's Twin Famicom. They function identically despite showing different intro during first boot.|
|Microphone||A Japan-exclusive built-in feature in the original Player 2 Famicom controller that allows players to use external sound source (e.g. player's voice) as input.||Legend of Zelda: The Hyrule Fantasy
Light Mythology: Palutena's Mirror
Virtual Console[N 3]
|Family BASIC||A Japan-exclusive peripheral that includes a enchanced dialect of BASIC programming language that allow users to create programs in Famicom. It comes with a special designed cartridge, keyboard, and the Data Recorder.||Family BASIC||Mesen
|Famicom Data Recorder||A Japan-exclusive compact cassette tape data interface as an addition to the Family BASIC to save data from BASIC programs created by users.||Family BASIC||Mesen
|Famicom 3D System||A Japan-exclusive active shutter glasses headset which allowed compatible games to display a stereoscopic image for 3D experience.||Famicom Grand Prix II: 3D Hot Rally
|RetroArch||GLSL shaders is needed for RetroArch to simulate the 3D experience with VR headset, 3D TV, 3D projector or Android phone with cardboard.|
|Miracle Piano Teaching System||An accessory that used an electronic MIDI keyboard as input.||Miracle Piano Teaching System||MAME
ASCII TurboFile II
|A Japan-exclusive external storage devices for saving game positions on Famicom.||Wizardry: Proving Grounds of the Mad Overlord
Wizardry II: The Knight of Diamonds
Downtown Nekketsu Monogatari
Haja no Fūin
|Oeka Kids Tablet||A Japan-exclusive drawing tablet for the Famicom Oeka Kids series.||Oeka Kids: Anpanman no Hiragana Daisuki
Oeka Kids: Anpanman to Oekaki Shiyou!!
|RacerMate CompuTrainer Pro||A rare series of peripherals for the game RacerMate Challenge II. It comes with a interface box, a bike trainer as well as a handlebar display.||RacerMate Challenge II||N/A||N/A|
|Game Genie||A pass-through devices that attached between a cartridge and the console, allowing the player to manipulate various aspects of games and access unused assets and functions by temporarily modify game data.||Various||FCEUX[N 4]
|Most emulators have a GUI to manage cheats and don't rely on real hardware cheating devices.|
|Family Computer Network System
|A Japan-exclusive network peripheral that allowed users to connect to a Nintendo server which provided extra content such as jokes, news, game tips, weather forecasts, horse betting and downloadable content via dial-up modem.||N/A||N/A||N/A|
- Up to three players only.
- Cheated by pressing any specific key ("M" by default).
- Through an actual microphone.
- Cheat authentically by using a Game Genie ROM.
An arcade system based on the NES released for the US. It was released in two different cabinet variations: Vs. UniSystem and Vs. DualSystem, which the later have double chipsets on the PCB and is capable of handling two different programs or simply two separate copies of a single program simultaneously.
Most emulators support games in Vs. UniSystem cabinet by setting up different DIP switches. But for games in Vs. DualSystem cabinet, MAME is the only choice.
Since most VS. System games have palettes that differ from the standard RGB NES palette, roms made with VS. System which are accidentally played in the emulator's NES mode (or vice-versa) will cause the colors to be totally garbled. This can occur when there is an issue with the emulator's configuration or the ROM's iNES header.
Also re-released later as Sharp's FamicomStation. The hybrid NES/Famicom arcade box Nintendo Famicom Box is a bulky metal cube, with a slot to insert money and secured with tons of locks. The hotel would set the amount of time you could play on one token, and choose the games available. You can see it in action in season 18 of Game Center CX. It was distributed in select hotels and stores and can hold up to 15 select Famicom releases at once, and had many more hardware lockout chips and pins with different behavior than usual (it also only supported cartridges using memory mapper 0). Sports a unique boot screen for both models released.
Neither the cartridges nor the BIOS has been dumped or tested with an emulator, unlike the Super Famicom Box (which has had both its BIOS' and most of its ROMs dumped).
A pirate NES Famicom clone which was sold in Russia and Eastern Europe, with the blueprint later reused for other Famiclones. Here's a link to a CC-subtitled Kinaman video for more details. It's a very quirky NTSC NES optimized for 50Hz, with many other changes from the official PAL NES as well- through these differences often break the compatibility of Dendy-specific releases on most emulators.
MESS supports this console, and some other emulators (such as Mesen, puNES, and FCEUX) have introduced support for it, as well as support for iNES 2.0 ROM headers (including the option to mark a ROM region as PAL Dendy). The cartridges themselves can still be played as long as the emulator supports broken carts.
VTxx is a series of NOAC (Nintendo-On-A-Chip, a kind of chip that contains all the components of a Famicom/NES) chips that implemented multiple changes and enhancements compared to regular NES, manufactured by V.R Technology.
Differences between VTxx series chips and regular NES could be checked on NesDev Wiki.
VTxx is often being used in those low-quality plug & play consoles, or keyboard-shaped so-called educational computers.
V.R technology provides an emulator called EmuVT as official development & debugging tool, which supports the emulation of multiple kinds of VTxx series chips, and seems to be modded out of an old emulator called NNNesterJ.
NES Classic Edition
- Main article: wikipedia:NES Classic Edition
The NES Classic Edition is a mini console that emulates the experience of the Nintendo Entertainment System. It includes 30 classic NES games and is compatible with the Wii Classic Controller and NES Classic Edition controller. Nintendo produced and sold about 2.3 million NES Classic Editions from November 2016 through April 2017, with shipments selling out nearly immediately. In April 2017, Nintendo announced they were discontinuing the product, leading to consumer confusion, and incidents of greatly increased pricing among private sellers. Due to the demand of the NES Classic, and the success of the Super NES Classic Edition console, Nintendo re-introduced the NES Classic on June 29, 2018. Production was discontinued again in December 2018.
- Nesdev Wiki - A place for all your NES programming/NES emulator programming needs.
- Nesdev Forum - Discussion of NES Wii Virtual Console accuracy.