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Super Nintendo Entertainment System

[REDACTED] [REDACTED]
Manufacturer	Nintendo
Type	Video game console
Generation	Fourth generation (16-bit era)
Lifespan	November 21, 1990 August 13, 1991 April 11, 1992 July 3, 1992
Units sold	49 million
Media	Game Pak
CPU	16-bit 65c816 Ricoh 5A22 3.58 MHz
Online services	Satellaview (Japan Only), XBAND
Best-selling game	Super Mario World
Predecessor	Nintendo Entertainment System
Successor	Nintendo 64

The Super Nintendo Entertainment System or Super NES (also called SNESTemplate:Hcref and Super Nintendo) is a 16-bit video game console released by Nintendo in North America, Europe, and Australia between 1990 and 1992. In Japan and Southeast Asia, the system is called the Super Family Computer, Super Famicom (スーパーファミコン, Sūpā Famikon), or SFC for short. In South Korea, it is known as the Super Comboy and was distributed by Hyundai Electronics. Although each version is essentially the same, several forms of regional lockout prevent direct compatibility.

The Super Nintendo Entertainment System is Nintendo's second home console, following the Nintendo Entertainment System (NES). The console introduced advanced graphics and sound capabilities that compensated for its relatively slow CPU, compared with other consoles at the time. Additionally, the system's support for numerous enhancement chips (which shipped as part of certain game cartridges) helped to keep it competitive in the marketplace.

The SNES was a global success, becoming the best-selling console of the 16-bit era despite its relatively late start and the fierce competition it faced in North America from Sega's Genesis console. The SNES remained popular well into the 32-bit era, and although Nintendo has dropped all support for the console, it continues to be popular among fans, collectors, and emulation enthusiasts, many of whom are still making "homebrew" ROM images.

Technical specifications

The design of the Super NES incorporates a relatively low-performance CPU (half the speed of the Mega Drive), but the powerful graphics and sound co-processors allowed impressive tiling and Mode 7 effects, many times more colors, and audio quality that represented a massive leap over the competition. Individual game cartridges can easily supply further custom chips as needed.

Central processing unit

The CPU is a Nintendo-custom 5A22 processor, based around a 16-bit CMD/GTE 65c816 core. The CPU employs a variable bus speed depending on the memory region being accessed for each instruction cycle: the input clock is divided by 6, 8, or 12 to obtain the bus clock rate. Non-access cycles, most register accesses, and some general accesses use the divisor of 6. WRAM accesses and other general accesses use the divisor of 8. Only the controller port serial-access registers use the divisor of 12.

The chip has an 8-bit data bus, controlled by two address buses. The 24-bit "Bus A" is used for general accesses, while the 8-bit "Bus B" is used for support chip registers (mainly the video and audio processors). Normally only one bus is used at a time, however the built in direct memory access (DMA) unit places a read signal on one bus and a write signal on the other to achieve block transfer speeds of up to 2.68 MB/s (MiB/s).

The DMA unit has 8 independent channels, each of which can be used in two modes. General DMA transfers up to 64 KB in one shot, while H-blank DMA (HDMA) transfers 1–4 bytes at the end of each video scanline. HDMA is typically used to change video parameters to achieve effects such as perspective, split-screen, and non-rectangular windowing without tying up the main CPU.

The 5A22 also contains an 8-bit parallel I/O port (which was mostly unused in the SNES); controller port interface circuits, including both serial and parallel access to controller data; a 16-bit multiplication and division unit; and circuitry for generating NMI interrupts on V-blank and IRQ interrupts on calculated screen positions.

Video

The picture processing unit (PPU) consists of two separate but closely tied IC packages, which may be considered as a single entity. It also contains 64 KB (KiB) of SRAM for storing video data (VRAM), 544 bytes of object attribute memory (OAM) for storing sprite data, and 512 bytes of color generator RAM (CGRAM) for storing palette data. The PPU is clocked by the same signal as the CPU, and generates a pixel every two or four cycles. Both NTSC and PAL systems use the same PPU chips, with one pin per chip selecting NTSC or PAL operation.

Images may be output at 256 or 512 pixels horizontal resolution and 224, 239, 448, or 478 pixels vertically. Vertical resolutions of 224 or 239 are usually output in progressive scan, while 448 and 478 resolutions are interlaced. Colors are chosen from the 15-bit RGB color space, for a total of 32,768 possible colors. Graphics consist of up to 128 sprites and up to 4 background layers, all made up of combinations of 8x8 pixel tiles. Most graphics use palettes stored in CGRAM, with color 0 of any palette representing transparency.

Sprites can be 8x8, 16x16, 32x32, or 64x64 pixels, each using one of eight 16-color palettes and tiles from one of two blocks of 256 in VRAM. Sprites may be flipped horizontally and vertically as a whole. Up to 32 sprites and 34 8x8 sprite tiles may appear on any one line; exceeding these limits causes excess sprites or tiles to be dropped. Each sprite lies on one of 4 planes, however a lower-numbered sprite will always cover a higher-numbered sprite even if the latter is on a higher priority plane. This quirk is often used for complex clipping effects.

Background layers in most modes range from 32x32 to 128x128 tiles, with each tile on one of two planes ("foreground" and "background") and using one of 8 palettes. Tiles are taken from a per-layer set of up to 1024 (as VRAM permits) and can be flipped horizontally and vertically. Each layer may be scrolled both horizontally and vertically. The number of background layers and the size of the palettes depends on the mode:

• Mode 0: 4 layers, all using 4-color palettes.
• Mode 1: 3 layers, two using 16-color palettes and one using 4-color palettes.
• Mode 2: 2 layers, both using 16-color palettes. Each tile can be individually scrolled.
• Mode 3: 2 layers, one using the full 256-color palette and one using 16-color palettes. The 256-color layer can also directly specify colors from an 11-bit (RGB443) colorspace.
• Mode 4: 2 layers, one using the full 256-color palette and one using 4-color palettes. The 256-color layer can directly specify colors, and each tile can be individually scrolled.
• Mode 5: 2 layers, one using 16-color palettes and one using 4-color palettes. Tile decoding is altered to facilitate use of the 512-width and interlaced resolutions.
• Mode 6: 1 layer, using 16-color palettes. Tile decoding is as in Mode 5, and each tile can be individually scrolled.

• Mode 7: 1 layer of 128x128 tiles from a set of 256, which may be interpreted as a 256-color one-plane layer or a 128-color two-plane layer. The layer may be rotated and scaled using matrix transformations. HDMA is often used to change the matrix parameters for each scanline to generate perspective effects.

Background layers may be individually pixelized, and layers and sprites can be individually clipped and combined by color addition or subtraction to generate more complex effects and greater color depths than can be specified directly.

The PPU may be instructed to latch the current pixel position at any time during image output, both by game software and by the device attached to controller port 2. The game software may then read back this latched position. The PPU may also be used for fast 16-bit by 8-bit signed multiplication.

Audio

The audio subsystem consists of an 8-bit Sony SPC700, a 16-bit DSP, 64 KB (KiB) of SRAM shared by the two chips, and a 64 byte boot ROM. The audio subsystem is almost completely independent from the rest of the system: it is clocked at a nominal 24.576 MHz in both NTSC and PAL systems, and can only communicate with the CPU via 4 registers on Bus B.

RAM is accessed at 3.072 MHz, with accesses multiplexed between the SPC700 (1⁄3) and the DSP (2⁄3). This RAM is used to store the SPC700 program and stack, the audio sample data and pointer table, and the DSP's echo buffer.

The SPC700 runs programs (uploaded using the boot ROM program) to accept instructions and data from the CPU and to manipulate the DSP registers to generate the appropriate music and sound effects. The DSP generates a 16-bit waveform at 32 kHz by mixing input from 8 independent voices and an 8-tap FIR filter typically used for reverberation. Each voice can play its PCM sample at a variable rate, with Gaussian interpolation, stereo panning, and ADSR, linear, non-linear, or direct volume envelope adjustment. The voice and FIR filter outputs are mixed both for direct output and for future input into the FIR filter. All audio samples are ADPCM compressed using Bit Rate Reduction.

Hardware on the cartridge, expansion port, or both can provide stereo audio data for mixing into the DSP's analog audio output before it leaves the console.

Since the audio subsystem is mostly self-contained, the state of the audio subsystem can be saved as an .SPC file, and the subsystem can be emulated in a stand-alone manner to play back game music.

Onboard RAM

The console contains 128 KB (KiB) of DRAM. This is mapped to various segments of Bus A, and can also be accessed in a serial fashion via registers on Bus B. The video and audio subsystems contain additional RAM reserved for use by those processors.

Regional lockout

Nintendo employed several types of regional lockout, including both physical and hardware incompatibilities.

On a physical level, the game paks are shaped differently for different regions. North American cartridges have a rectangular bottom with inset grooves matching protruding tabs in the console, while other regions' cartridges are narrower with a smooth curve on the front and no grooves. The physical incompatibility can be overcome with use of various adapters, or through modification of the console.

Internally, a regional lockout chip (CIC) within the console and in each cartridge prevents PAL region games from being played on Japanese or North American consoles and vice versa. The Japanese and North American machines have the same region chip. The console CIC releases the reset signal to the rest of the system only after completing a handshake with the chip in the cartridge. This can be overcome through the use of adapters, typically by inserting the imported cartridge in one slot and a cartridge with the correct region chip in a second slot. Alternatively, disconnecting one pin of the console's lockout chip will prevent it from locking the console; hardware in later games can detect this situation, so it later became common to install a switch to reconnect the lockout chip as needed.

PAL consoles face another incompatibility when playing out-of-region cartridges: the NTSC video standard specifies video at 60 Hz while PAL operates at 50 Hz, resulting in approximately 16.7% slower gameplay. Additionally, PAL's higher resolution results in letterboxing of the output image. Some commercial PAL region releases exhibit this same problem and therefore can be played in NTSC systems without issue, while others will face a 20% speedup if played in an NTSC console. To mostly correct this issue, a switch can be added to place the SNES PPU into a 60 Hz mode supported by most PAL televisions. Later games will detect this setting and refuse to run, requiring the switch to be thrown only after the check completes.

Casing

Original U.S. version	Original PAL version	Super Famicom Jr.

All versions of the SNES are predominantly gray, although the exact shade may differ. The original North American version has a boxy design with purple sliding switches and a dark gray eject lever. The Japanese and European versions are more rounded, with darker gray accents and buttons. The North American SNES 2 and the Japanese Super Famicom Jr. are both smaller with a rounded contour, however the SNES 2 buttons are purple where the Super Famicom Jr. buttons are gray.

All versions incorporate a top-loading slot for game cartridges, although the shape of the slot differs between regions to match the different shapes of the cartridges. The card-edge connector has 62 pads, however many cartridges only connect to the middle 46. All versions also incorporate two 7-pin controller ports on the front of the unit, and a plug for a power supply and a Nintendo-proprietary "multi-out" A/V connector on the back. The multi-out connector, later used on the Nintendo 64 and GameCube, can output RF, RGB, S-Video, and composite video signals. Original versions additionally include a 28-pin expansion port under a small cover on the bottom of the unit and a standard RF output with channel selection switch on the back; newer versions use the RF capability of the multi-out connector.

Game cartridge

While the SNES can address 128 Mb (Mib), only 117.75 Mb are actually available for cartridge use. A fairly normal mapping could easily address up to 95 Mb of ROM data (48 Mb at FastROM speed) with 8 Mb of battery-backed RAM. However, most available memory access controllers only support mappings of up to 32 Mb. The largest games released (Star Ocean and Tales of Phantasia) contain 48 Mb of ROM data, while smallest games contain only 2 Mb.

Cartridges may also contain battery-backed SRAM to save the game state, extra working RAM, custom coprocessors, or any other hardware that will not exceed the maximum current rating of the console.

Peripherals

The SNES standard controller adds two additional buttons to the standard NES design, arranging the four in a diamond shape, and two shoulder buttons. It also features an ergonomic design later used for the NES 2. The Japanese and PAL region versions incorporate the system's logo in the colors of the four action buttons, while the North American version colors them lavender and purple to match the redesigned console. Many believe that several later consoles derive their controller design from the SNES, including the PlayStation, PS2, PS3, Dreamcast, Xbox, Xbox 360, and Wii (Classic Controller).

Throughout the course of its life, a number of peripherals were released which added to the functionality of the SNES. Many of these devices were modeled after earlier add-ons for the NES: the Super Scope is a light gun similar to the NES Zapper (though the Super Scope features wireless capabilities) and the Super Advantage is an arcade-style joystick with adjustable turbo settings akin to the NES Advantage. Nintendo also released the SNES Mouse in conjunction with its Mario Paint title. Hudson Soft, under license from Nintendo, released the Super Multitap, a multiplayer adapter for use with its popular series of Bomberman games. Some of the more unusual controllers include the BatterUP baseball bat and TeeV Golf golf club.

While Nintendo never released an adapter for playing NES games on the SNES, the Super Game Boy adapter cartridge allows games designed for Nintendo's portable Game Boy system to be played on the SNES. The Super Game Boy touted several feature enhancements over the Game Boy, including palette substitution, custom screen borders, and (for specially enhanced games) access to the SNES console.

Like the NES before it, the SNES saw its fair share of unlicensed third-party peripherals, including a new version of the Game Genie cheat cartridge designed for use with SNES games and a variety of game copier devices. In general, Nintendo proved to be somewhat more tolerant of unlicensed SNES peripherals than they had been with NES peripherals.

Soon after the release of the SNES, companies began marketing backup devices such as the Super Wildcard, Super Pro Fighter Q, and Game Doctor. These devices were sold to create a backup of a cartridge, in the event that it would break. However, they could also be used to play copied ROM images that could be downloaded from BBSes and the Internet, or to create copies of rented video games, often violating copyright laws in many jurisdictions.

Japan saw the release of the Satellaview, a modem which attached to the Super Famicom's expansion port and connected to the St. GIGA satellite radio station. Users of the Satellaview could download gaming news and specially designed games, which were frequently either remakes of or sequels to older Famicom titles, released in installments. Satellaview signals were broadcast from April 23, 1995 through June 30, 2000. In the United States, the similar but relatively short-lived XBAND allowed users to connect to a network via a dial-up modem to compete against other players around the country.

During the SNES's life, Nintendo contracted with two different companies to develop a CD-ROM-based peripheral for the console to compete with Sega's CD-ROM based addon, Sega CD. Ultimately, negotiations with both Sony and Philips fell through, and the two companies went on to develop their own consoles based on their initial dealings with Nintendo (the PlayStation and the CD-i respectively), Philips also gaining the right to release a series of CD-i titles based on Nintendo franchises.

Enhancement chips

As part of the overall plan for the SNES, rather than include an expensive CPU that would still become obsolete in a few years, the hardware designers made it easy to interface special coprocessor chips to the console. This is most often characterized by 16 additional pins on the cartridge card edge.

The Super FX is a RISC CPU designed to perform functions that the main CPU could not feasibly do. The chip was primarily used to create 3D game worlds made with polygons, texture mapping and light source shading. The chip could also be used to enhance 2D games.

The Nintendo fixed-point digital signal processor (DSP) chip allowed for fast vector-based calculations, bitmap conversions, both 2D and 3D coordinate transformations, and other functions. Four revisions of the chip exist, each physically identical but with different microcode. The DSP-1 version, including the later 1A and 1B bug fix revisions, was most often used; the DSP-2, DSP-3, and DSP-4 were used in only one title each.

Similar to the 5A22 CPU in the console, the SA-1 chip contains a 65c816 processor core clocked at 10 MHz, a memory mapper, DMA, decompression and bitplane conversion circuitry, several programmable timers, and CIC region lockout functionality.

In Japan, games could be downloaded for a fee from Nintendo Power kiosks onto special cartridges containing flash memory and a MegaChips MX15001TFC chip. The chip managed communication with the kiosks to download ROM images, and provided an initial menu to select which of the downloaded games would be played. Some titles were available both in cartridge and download form, while others were download only. The service was closed on February 8, 2007.

Many cartridges contain other enhancement chips, most of which were created for use by a single company in a few titles; the only limitations are the speed of the Super NES itself to transfer data from the chip and the current rating of the console.

Market share

49 million Super NES units were sold worldwide, 20 million of which were sold in the U.S. Although it could not repeat the success of the NES, which sold over 60 million units worldwide, the Super NES was the best-selling console of its era. The Mega Drive came in second with 29 million sold worldwide, and the TurboGrafx-16 was third with 10 million sold worldwide.

See also

v t e Dedicated consoles
Home	Original APF TV Fun series Coleco Telstar series Arcade Marksman Color TV-Game Plug It In & Play TV Games Stunt Cycle Video Pinball Retro Atari Flashback series C64 Direct-to-TV NES Classic Edition PlayStation Classic Sega Genesis Mini Super NES Classic Edition TurboGrafx-16 Mini
Handheld	Bemani Pocket Coleco Sonic Game & Watch VG Pocket Max Pokémon Pikachu Tomytronic 3D
List

• List of SNES games
• List of Super Famicom games
• List of SNES emulators
• List of Player's Choice games

Content notes

 a: The acronym SNES can be pronounced by English speakers as a single word (compare "NATO") in different ways, an initialism (compare "IBM"), or as a hybrid (compare "JPEG"); some even claim SNES should be pronounced "Super Nintendo" or "Super NES". In written English, the choice of indefinite article can be problematic due to these differences in pronunciation.
 b: Various sources report dates from August 13 to September 9, with some citing supply issues and others claiming various retailers began selling the system before the official release date.
 c: While some contend that Nintendo orchestrated the Congressional hearings of 1993, Senator Lieberman and NOA's Senior Vice President (later Chairman) Howard Lincoln both refute these allegations.
 d: As opposed to emulation "good enough" for most purposes, exact emulation facilitates the use of the emulator for homebrew game development and documents the operation of the hardware against such time as all existing consoles cease functioning.

References

1. ^ "Super Nintendo Entertainment System". Classic Systems. Nintendo of America. Retrieved 2007-05-10.
2. Jeremy Parish (2005-09-06). "PS1 10th Anniversary retrospective". 1UP.com. Retrieved 2007-05-27. {{cite web}}: Check date values in: |date= (help)
3. ^ anomie. "Anomie's SNES Memory Mapping Doc" (text). Romhacking.net. Retrieved 2007-04-21. {{cite web}}: External link in |publisher= (help)
4. ^ anomie. "Anomie's Register Doc" (text). Romhacking.net. Retrieved 2007-04-21. {{cite web}}: External link in |publisher= (help)
5. ^ anomie. "Anomie's S-DSP Doc" (text). Romhacking.net. Retrieved 2007-04-21. {{cite web}}: External link in |publisher= (help)
6. anomie. "Anomie's SPC700 Doc" (text). Romhacking.net. Retrieved 2007-04-21. {{cite web}}: External link in |publisher= (help)
7. ^ anomie. "Anomie's SNES Port Doc" (text). Romhacking.net. Retrieved 2007-07-13. {{cite web}}: External link in |publisher= (help)
8. ^ Lou Cassaniti (1999-03-03). "Super Nintendo/Famicom F.A.Q." (text). Gamers Graveyard. Retrieved 2007-04-14. {{cite web}}: Check date values in: |date= (help); External link in |publisher= (help)
9. Mark Knibbs (1997-12-27). "Disabling the Super NES/Super Famicom "Lockout Chip"" (text). Retrieved 2007-04-14. {{cite web}}: Check date values in: |date= (help)
10. Mark Knibbs (1998-01-25). "Super NES/Super Famicom 50/60Hz Switch Modification" (text). Retrieved 2007-04-14. {{cite web}}: Check date values in: |date= (help)
11. Sud Koushik (2006-01-30). "Evolution of Controllers". Advanced Media Network. Retrieved 2007-05-25. {{cite web}}: Check date values in: |date= (help)
12. Chris Bateman (2006-05-11). "Sony's Copycat Policy". Only a Game. Retrieved 2007-05-25. {{cite web}}: Check date values in: |date= (help)
13. Chris Kohler (2005-09-13). "Controller's History Dynamite". 1UP.com. p. 4. Retrieved 2007-05-25. {{cite web}}: Check date values in: |date= (help)
14. John Honniball. "Evolution of the Game Pad". Retrieved 2007-05-19.
15. Phil (2007-04-27). "SNES Controller: The Most Influential Game Pad Ever?". Shamoozal Nerdlog. Retrieved 2007-05-25. {{cite web}}: Check date values in: |date= (help)
16. Alex Ricciardi, Sam Speer. "SYSTEMS - SNES". NGEB. Retrieved 2007-05-20.
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18. "Super GameBoy". Gamers Graveyard. Retrieved 2007-07-02. {{cite web}}: External link in |publisher= (help)
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20. Glen Bayer. "NintendOnline". N-Sider.com. Retrieved 2007-05-30.
21. Glen Bayer. "SNES-CD Profile". N-Sider.com. Retrieved 2007-04-14.
22. ^ (2007-05-01) Snes9x readme.txt v1.51. snes9x.com. Retrieved on 2007-07-03.
23. Overload (2006-05-29). "Digital Signal Processing". Overload's Puzzle Sheet. Retrieved 2007-05-09. {{cite web}}: Check date values in: |date= (help) Refer to the command summaries for all four DSP versions.
24. ^ Nach. "SNES Add-on Chip information". Retrieved 2007-05-09. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
25. "Nintendo Power". N-Sider.com. Retrieved 2007-07-03.
26. "Nintendo Entertainment System". Classic Systems. Nintendo of America. Retrieved 2007-07-23.
27. Ken Polsson. "Chronology of Sega Video Games". Retrieved 2007-05-10.
28. Blake Snow (2007-05-04). "The 10 Worst-Selling Consoles of All Time". GamePro.com. Retrieved 2007-05-28. {{cite web}}: Check date values in: |date= (help)
29. "Do you say NES or N-E-S?". Nintendo NSider Forums. Retrieved 2007-05-16.
30. "Pronouncing NES & SNES". Gamespot forums. Retrieved 2007-05-16.
31. Ray Barnholt (2006-08-04). "Purple Reign: 15 Years of the Super NES". 1UP.com. pp. p. 2. Retrieved 2007-06-14. {{cite web}}: |pages= has extra text (help); Check date values in: |date= (help) States August 13.
32. "Super Nintendo Entertainment System". N-Sider.com. Retrieved 2007-06-14. States August 13.
33. Glen Bayer. "SNES-CD Profile". N-Sider.com. Retrieved 2007-06-14. States September 9.
34. Kent, Steven L. The Ultimate History of Video Games: The Story Behind the Craze that Touched our Lives and Changed the World. Roseville, California: Prima Publishing. pp. p. 434. ISBN 0-7615-3643-4. {{cite book}}: |pages= has extra text (help) States September 1 was planned but later rescheduled to September 9.
35. Cite error: The named reference Kent_MK was invoked but never defined (see the help page).

External links

• The official Nintendo Corp. homepage
• Nintendo of America's "Classic System" page on the SNES
• SNES infomation at Nintendo UK & Ireland

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• Super NES
• Video game console remakes (article section)
• Fourth-generation video game consoles
• 1990 introductions
• 1991 introductions
• 1992 introductions