Super Nintendo Entertainment System

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Super Nintendo Entertainment System
Super Nintendo Entertainment System logo.svg
Nintendo Super Famicom logo.svg
The North American SNES (circa 1991)
A Japanese Super Famicom
Top: North American SNES (circa 1991)
Bottom: Japanese Super Famicom, which has the same casing later used in European and Australian consoles.
Other variations are pictured under Casing below
Also known as SNES
Super NES

JP: Super Famicom
KOR: Super Comboy
Super Nintendo
Manufacturer Nintendo
Type Home video game console
Generation Fourth generation
Release date JP: November 21, 1990
NA: August 23, 1991
UK: April 11, 1992
IRL: April 11, 1992
EU: June 1992
AUS: July 3, 1992
BR: August 30, 1993
Retail availability 1990–2003
Introductory price JP¥25,000
US$199
Discontinued JP: September 25, 2003
NA: 1999
EU: 1998
BR: 2003
KOR: April 1, 2003
Units sold Worldwide: 49.10 million
North America: 23.35 million
Japan: 17.17 million
Other: 8.58 million
Media ROM cartridge
CPU WDC 65C816 @ 3.58 MHz
Sound Nintendo S-SMP
Online services Satellaview (Japan only)
XBAND
Nintendo Power (Japan only)
Best-selling game
Predecessor Nintendo Entertainment System
Successor Nintendo 64

Introduction[edit]

The Super Nintendo Entertainment System (SNES), is a 16-bit home video game console developed by Nintendo that was released in 1990 in Japan and South Korea, 1991 in North America, 1992 in Europe and Australasia (Oceania), and 1993 in South America. In Japan, the system is called the Super Famicom (SFC). In South Korea, it is known as the Super Comboy and was distributed by Hyundai Electronics. The system was released in Brazil on August 30, 1993, by Playtronic. Although each version is essentially the same, several forms of regional lockout prevent the different versions from being compatible with one another.

The SNES is Nintendo's second programmable home console, following the Nintendo Entertainment System (NES). The console introduced advanced graphics and sound capabilities compared with other systems at the time. The development of a variety of enhancement chips integrated in 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 intense competition it faced in North America and Europe from Sega's Genesis console. The SNES remained popular well into the 32-bit era having sold 49.1 million worldwide (Comparative to the NES's 61.9 million). It continues to be popular among collectors and retro gamers, some of whom still make homebrew ROM images, in addition to its popularity in Nintendo's emulated rereleases, such as in Virtual Console environment.

Specifications[edit]

Technical specifications[edit]

The 16-bit design of the SNES incorporates graphics and sound co-processors that perform tiling and simulated 3D effects, a palette of 32,768 colors, and 8-channel ADPCM audio. These base platform features, plus the ability to dramatically extend them all through substantial chip upgrades inside of each cartridge, represent a leap over the 8-bit NES generation and some supposed significant advantages over 16-bit competitors such as the Genesis.

Central processing unit and RAM[edit]

CPU reference
Processor 16-bit Custom WDC 65C816 core
Clock rates (NTSC) Input: 21.47727 MHz
Bus: 3.58 MHz, 2.68 MHz, or 1.79 MHz
Clock rates (PAL) Input: 21.28137 MHz
Bus: 3.55 MHz, 2.66 MHz, or 1.77 MHz
Buses 24-bit and 8-bit address buses, 8-bit data bus
Additional features
  • DMA and HDMA
  • Timed IRQ
  • Parallel I/O processing
  • Hardware multiplication and division

The CPU is a WDC 65C816. It is a derivative of the 16-bit 65C816. In NTSC regions, its nominal clock speed is 3.58 MHz but the CPU will slow down to either 2.68 MHz or 1.79 MHz when accessing some slower peripherals.

This CPU has an 8-bit data bus and two address buses. The 24-bit "Bus A" is used for general accesses, while the 8-bit "Bus B" is used to access support chip registers such as the video and audio co-processors.

The WDC 65C816 also supports an 8-channel DMA unit; an 8-bit parallel I/O port a controller port interface circuits allowing serial and parallel access to controller data; a 16-bit multiplication and division unit; and circuitry for generating non-maskable interrupts on V-blank and IRQ interrupts on calculated screen positions.

The console contains 128 KB of general-purpose RAM, which is separate from the RAM dedicated to the video and audio subsystems.

Video[edit]

Video reference
Resolutions Progressive: 256×224, 512×224, 256×239, 512×239
Interlaced: 512×448, 512×478
Pixel depth 2, 4, 7, or 8 bpp indexed; 8 or 11 bpp direct
Total colors 32768 (15-bit)
Sprites 128, 32 max per line; up to 64 × 64 pixels
Backgrounds Up to 4 planes; each up to 1024 × 1024 pixels
Effects
  • Pixelization (mosaic) per background
  • Color addition and subtraction
  • Clipping windows (per background, affecting color, math, or both)
  • Scrolling per 8 × 8 tile
  • Mode 7 matrix operations

The Picture Processing Unit (PPU) consists of two separate but closely tied IC packages. It contains 64 KB of SRAM for storing video data, 544 bytes of object attribute memory (OAM) for storing sprite data, and 256 × 15 bits of color generator RAM (CGRAM) for storing palette data. This CGRAM allows the console to display up to 256 colors, chosen from the 15-bit RGB color space, for a total of 32,768 possible colors. The PPU is clocked by the same signal as the CPU, and generates a pixel every two or four cycles. Seven video modes are available to the programmer:

  • Mode 0: 4 layers, all using 4-color palettes. Each BG uses its own section of the SNES palette. Up to 96 colors can be displayed on the backgrounds, 24 colors per layer.
  • Mode 1: 3 layers, two using 16-color palettes and one using 4-color palettes. Up to 120 colors can be displayed by first two layers and 24 colors by third layer.
  • Mode 2: 2 layers, both using 16-color palettes. Each tile can be individually scrolled. Up to 120 colors can be displayed on screen.
  • 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. Up to 256 colors displayed by first layer and 120 colors by second layer.
  • 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. Up to 256 colors displayed by first layer and 24 colors by second layer.
  • 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. Up to 120 colors displayed by first layer and 24 colors by second layer.
  • Mode 6: 1 layer, using 16-color palettes. Tile decoding is as in Mode 5, and each tile can be individually scrolled. Up to 120 colors can be displayed on screen.
  • Mode 7: 1 layer of 128×128 tiles of size 8×8 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. A programming technique called HDMA can be used to change the matrix parameters for each scanline in order to generate perspective effects.

Audio[edit]

Audio reference
Processors Nintendo S-SMP
Clock rates Input: 24.576 MHz
SPC700: 1.024 MHz
Output 8 channels, stereo
Effects
  • ADSR envelope control
  • Frequency scaling and modulation using Gaussian interpolation
  • Echo: 8-tap FIR filter, with up to .24s delay
  • Noise generation

The audio subsystem, the S-SMP, is a dedicated single chip consisting of an 8-bit CPU, along with a 16-bit DSP, and 64 KB of SRAM. It is designed and produced by Sony and is completely independent from the rest of the system. It is clocked at a nominal 24.576 MHz in both NTSC and PAL systems. It is capable of producing stereo sound, composed from 8 voices generated using 16 bit audio samples and various effects such as reverberation.

Regional lockout[edit]

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

A cartridge shape comparison
Top: North American design
Bottom: Japanese and PAL region design.
The bottom cartridge also illustrates the optional pins used by enhancement chips such as the Super FX 3D chip.

On a physical level, the cartridges 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. 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 framerate. 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 other games 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 newer PAL televisions. Later games will detect this setting and refuse to run, requiring the switch to be thrown only after the check completes.

Casing[edit]

Original Japanese SFC
Original U.S. SNES
Original PAL SNES
New-Style Super NES
Super Famicom Jr.
Super Comboy
Japanese SHVC-001 model
(1990–1998)
American SNS-001 model
(1991–1997)
PAL-region SNSP-001A model
(1992–1998)
New-Style Super NES SNS-101
(1997–1999)
Japanese SHVC-101 model
(1998–2003)
South Korean SNSN-001 model

All versions of the Super NES are predominantly gray, of slightly different shades. The original North American version, designed by Nintendo of America industrial designer Lance Barr (who previously redesigned the Famicom to become the NES), has a boxy design with purple sliding switches and a dark gray eject lever. The loading bay surface is curved, both to invite interaction and to prevent food or drinks from being placed on the console and spilling as had happened with the flat surfaced NES. The Japanese and European versions are more rounded, with darker gray accents and buttons. The North American New-style Super NES (model SNS-101) and the Japanese Super Famicom Jr. (model SHVC-101), all designed by Barr, are both smaller with a rounded contour; however, the SNS-101 buttons are purple where the Super Famicom Jr. buttons are gray. The European and American versions of the SNES controllers have much longer cables compared to the Japanese Super Famicom controllers.

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 MULTI OUT connector (later used on the Nintendo 64 and GameCube) can output composite video, S-Video and RGB signals, as well as RF with an external RF modulator. 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; the redesigned models output composite video only, requiring an external modulator for RF.

Yellowing of console plastic

The ABS plastic used in the casing of some older SNES and Super Famicom consoles is particularly susceptible to oxidization with exposure to air, likely due to an incorrect mixture of the stabilizing or flame retarding additives. This, along with the particularly light color of the original plastic, causes affected consoles to quickly become yellow; if the sections of the casing came from different batches of plastic, a "two-tone" effect results.

Game cartridge[edit]

The cartridge media of the console is officially referred to as Game Pak in most Western regions, and as Cassette in Japan and parts of Latin America. While the SNES can address 128 Mbit, only 117.75 Mbit are actually available for cartridge use. A fairly normal mapping could easily address up to 95 Mbit of ROM data (48 Mbit at FastROM speed) with 8 Mbit of battery-backed RAM. However, most available memory access controllers only support mappings of up to 32 Mbit. The largest games released (Tales of Phantasia and Star Ocean) contain 48 Mbit of ROM data, while the smallest games contain only 2 Mbit.

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[edit]

The North American SNES controller

The standard SNES controller adds X and Y face buttons to the design of the NES iteration, arranging the four in a diamond shape, and adds two shoulder buttons. It features an ergonomic design by Lance Barr, later used for the NES-102 model controllers, also designed by Barr. The Japanese and PAL region versions incorporate the colors of the four action buttons into the system's logo. The North American version's buttons are colored to match the redesigned console; the X and Y buttons are lavender with concave faces, and the A and B buttons are purple with convex faces. Several later consoles derive elements of their controller design from the SNES, including the PlayStation, Dreamcast, Xbox, 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 functionally 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 Mario Paint. 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, the Life Fitness Entertainment System (an exercise bike controller with built-in monitoring software), and the TeeV Golf golf club.

The Super Game Boy allows Game Boy games to be played on the SNES.

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 touts several feature enhancements over the Game Boy, including palette substitution, custom screen borders, and access to the SNES console's features by specially enhanced Game Boy games. Japan also saw the release of the Super Game Boy 2, which adds a communication port to enable a second Game Boy to connect for multiplayer games.

Like the NES before it, the SNES has unlicensed third-party peripherals, including a new version of the Game Genie cheat cartridge designed for use with SNES games.

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 create a backup of a cartridge. They can also be used to play illicit ROM images or to create copies of rented video games, violating copyright laws in many jurisdictions.

Satellaview with Super Famicom

Japan saw the release of the Satellaview, a modem which attaches to the Super Famicom's expansion port and connected to the St.GIGA satellite radio station from April 23, 1995 to June 30, 2000. Satellaview users could download gaming news and specially designed games, which were frequently either remakes of or sequels to older Famicom games, and released in installments. In the United States, the 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 add-on, Sega CD. Although a SNES-CD prototype console was produced by Sony, Nintendo's deals with both Sony and Philips were canceled, with Philips gaining the right to release a series of games based on Nintendo franchises for its CD-i multimedia console and Sony going on to develop its own PlayStation console based on its initial dealings with Nintendo.

Enhancement chips[edit]

Star Fox, the first game to utilize the Super FX chip, as shown with the polygonal models that compose a large portion of the game's graphics

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, just like the MMC chips used for most NES games. 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 can not feasibly do. The chip is primarily used to create 3D game worlds made with polygons, texture mapping and light source shading. The chip can 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, is used most often; the DSP-2, DSP-3, and DSP-4 are used in only one game 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 cheaper than standard cartridges, 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 were available both in cartridge and download form, while others were download only. The service 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 games; the only limitations are the speed of the SNES itself to transfer data from the chip and the current limit of the console.

Emulation[edit]

Like the NES before it, the SNES has retained a long-lived fan base. It has continued to thrive on the second-hand market, emulators, and remakes. The SNES has taken the same revival path as the NES.

Emulation projects began with the initial release of VSMC in 1994, and Super Pasofami became the first working SNES emulator in 1996. During that time, two competing emulation projects—Snes96 and Snes97—merged to form Snes9x. In 1997, SNES enthusiasts began programming an emulator named ZSNES. In 2004, higan began development as bsnes, in an effort to emulate the system as closely as possible.

Nintendo of America took the same stance against the distribution of SNES ROM image files and the use of emulators as it did with the NES, insisting that they represented flagrant software piracy. Proponents of SNES emulation cite discontinued production of the SNES constituting abandonware status, the right of the owner of the respective game to make a personal backup via devices such as the Retrode, space shifting for private use, the desire to develop homebrew games for the system (Nintendo designed a hobbyist development system for the Super NES, but never released it), the frailty of SNES ROM cartridges and consoles, and the lack of certain foreign imports.

Emulation of the Super NES is also available on platforms such as Android, and iOS, the Nintendo DS line, the Gizmondo, the Dingoo and the GP2X by GamePark Holdings, as well as PDAs. While individual games have been included with emulators on some GameCube discs, Nintendo's Virtual Console service for the Wii marks the introduction of officially sanctioned general SNES emulation.

A dedicated mini-console, the Super NES Classic Edition, was released in September 2017 after the NES Classic Edition. The emulation-based system, which is physically modeled after the North American and European versions of the SNES in their respective regions, is bundled with two SNES-style controllers and comes preloaded with 21 games, including the previously unreleased Star Fox 2.