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==Description==
==Description==
[[Image:2600IntCartridgeChip07052004.jpg|thumb|right|2600 game cartridge innards: basically a [[printed circuit board|circuit board]] with a [[read-only memory|ROM]] chip (center) and dual-sided 24-pin [[edge connector]] (bottom).]]
[[Image:2600IntCartridgeChip07052004.jpg|thumb|right|2600 game cartridge innards: basically a [[printed circuit board|circuit board]] with a [[read-only memory|ROM]] chip (center) and dual-sided 24-pin [[edge connector]] (bottom).]]
The basic layout of the 2600 is fairly similar to most consoles and home computers of the era. The CPU was the [[MOS Technology 6507]], a cut-down version of the 6502, running at 1.19 [[megahertz|MHz]] in the 2600. The 6507 included fewer memory address pins &mdash; 13 instead of 16 &mdash; and no external interrupts to fit into a smaller 28-pin package. Smaller packaging was, and still is, an important factor in overall system cost, and since memory was very expensive at the time, the 6507's small 8&nbsp;[[KiB]] of maximum external memory space wasn't going to be used up anyway. In fact, memory was so expensive they couldn't imagine using up even 4K, and when they got a deal on 24-pin connectors for the cartridge socket, they were only too happy to thereby limit the games to 4K.<ref name="cartridge-socket">The cartridge connector's 24 pins were allocated to one supply voltage line, two ground lines, 8 data lines, and 13 address lines. However, the uppermost address line was used as a so-called [[chip select]] for the cartridge's ROM chip, leaving only 12 address lines for the chip's game program. Thus, without special "hardware tricks" built into the cartridge, an Atari 2600 game could occupy a maximum address space of 4K.</ref> Later games got around this limitation with [[bank switching]].
The basic layout of the 2600 is fairly similar to most consoles and home computers of the era. The CPU was the [[MOS Technology 6507]], a cut-down version of the 6502, running at 1.19 [[megahertz|MHz]] in the 2600. The 6507 included fewer memory address pins &mdash; 13 instead of 16 &mdash; and no external interrupts to fit into a smaller 28-pin package. Smaller packaging was, and still is, an important factor in overall system cost, and since memory was very expensive at the time, the 6507's small 8&nbsp;[[kilobyte|KB]] of maximum external memory space wasn't going to be used up anyway. In fact, memory was so expensive they couldn't imagine using up even 4K, and when they got a deal on 24-pin connectors for the cartridge socket, they were only too happy to thereby limit the games to 4K.<ref name="cartridge-socket">The cartridge connector's 24 pins were allocated to one supply voltage line, two ground lines, 8 data lines, and 13 address lines. However, the uppermost address line was used as a so-called [[chip select]] for the cartridge's ROM chip, leaving only 12 address lines for the chip's game program. Thus, without special "hardware tricks" built into the cartridge, an Atari 2600 game could occupy a maximum address space of 4K.</ref> Later games got around this limitation with [[bank switching]].


The console had only 128 [[byte]]s of [[random-access memory|RAM]] for [[runtime]] data that included the [[call stack]] and the state of the game world. There was no [[frame buffer]], as the necessary RAM would have been too expensive. Instead the video device had two [[bitmap]]ped [[sprite (graphics)|sprites]], two one-line "missile" sprites, a one-pixel "ball," and a "playfield" that was drawn by writing a bit pattern for each line into a register just before the television scanned that line. As each line was scanned, a game had to identify the non-sprite objects that overlapped the next line, assemble the appropriate bit patterns to draw for those objects, and write the pattern into the register. By default the right side of the screen was a duplicate of the left; to control it separately, the software had to modify the patterns as the scan line was drawn. After the controller scanned the last active line, a more leisurely [[vertical blanking interval]] began, during which the game could process input and update the positions and states of objects in the world. Any mistake in timing produced visual artifacts, a problem programmers called ''racing the beam''.
The console had only 128 [[byte]]s of [[random-access memory|RAM]] for [[runtime]] data that included the [[call stack]] and the state of the game world. There was no [[frame buffer]], as the necessary RAM would have been too expensive. Instead the video device had two [[bitmap]]ped [[sprite (graphics)|sprites]], two one-line "missile" sprites, a one-pixel "ball," and a "playfield" that was drawn by writing a bit pattern for each line into a register just before the television scanned that line. As each line was scanned, a game had to identify the non-sprite objects that overlapped the next line, assemble the appropriate bit patterns to draw for those objects, and write the pattern into the register. By default the right side of the screen was a duplicate of the left; to control it separately, the software had to modify the patterns as the scan line was drawn. After the controller scanned the last active line, a more leisurely [[vertical blanking interval]] began, during which the game could process input and update the positions and states of objects in the world. Any mistake in timing produced visual artifacts, a problem programmers called ''racing the beam''.
Line 115: Line 115:


===Third-party peripherals===
===Third-party peripherals===
* [[Starpath Supercharger]], a cartridge with a [[compact audio cassette|cassette]] player connector, giving 6 1/8 [[KiB]] RAM capacity
* [[Starpath Supercharger]], a cartridge with a [[compact audio cassette|cassette]] player connector, giving 6 1/8 [[kilobyte|KB]] RAM capacity


* [[Gameline]] Master Module, a modem allowing downloads of games from an extensive catalog which could be playable for a limited amount of time.
* [[Gameline]] Master Module, a modem allowing downloads of games from an extensive catalog which could be playable for a limited amount of time.

Revision as of 17:53, 23 February 2007

Atari 2600
Atari 2600 four-switch "wood veneer" version (the original 2600 had six switches).
ManufacturerAtari
TypeVideo game console
GenerationSecond generation
LifespanUnited States October, 1977
Japan 1983
European Union 1980
Units soldapprox 40 million
MediaCartridge
CPUMOS Technology 6507
Best-selling gamePac-Man
PredecessorAtari PONG
SuccessorAtari 5200

The Atari 2600, released in October 1977, was the first successful video game console to use plug-in cartridges instead of having one or more games built in.[1] Originally known as the Atari VCS—for Video Computer System—the machine's name was changed to "Atari 2600" (from the unit's Atari part number, CX2600) in 1982, after the release of the more advanced Atari 5200. It was wildly successful, and during the 1980s, "Atari" was a synonym for this model in mainstream media. The 2600 was typically bundled with two joystick controllers, a conjoined pair of paddle controllers, and a cartridge game.

History

Development and market considerations

Atari had purchased an engineering think-tank in 1975 called Cyan Engineering to research next-generation video game systems, and had been working on a prototype known as "Stella" (named after one of the engineers' bicycles) for some time. Unlike prior generations of machines which used custom logic to play a small number of games, Stella's core was a complete CPU, the famous MOS Technology 6502 in a cost-reduced version, known as the 6507. It was combined with a RAM-and-I/O chip, the MOS Technology 6532, and a display and sound chip of their own design known as the TIA, for Television Interface Adaptor. Beyond those three, the first two versions of the machine contain just one more chip, a standard CMOS logic buffer IC, bringing the total chip count to the very low and cost-effective number of four. Some later versions of the console eliminated the buffer chip. At first the design was not going to be cartridge-based, but after seeing a "fake" cartridge system on another machine, they realized they could place the games on cartridges essentially for the price of the connector and packaging.

In August 1976, Fairchild Semiconductor released their own CPU-based system, the Video Entertainment System. Stella was still not ready for production, but it was clear that it needed to be before there were a number of "me too" products filling up the market – which had happened after they released PONG. Atari simply didn't have the cash flow to complete the system quickly, given that sales of their own PONG systems were cooling. Nolan Bushnell eventually turned to Warner Communications, and sold the company to them in 1976 for US$28 million on the promise that Stella would be produced as soon as possible.

Key to the eventual success of the machine was the hiring of Jay Miner, a chip designer who managed to squeeze an entire breadboard of equipment making up the TIA into a single chip. Once that was completed and debugged the system was ready for shipping. By the time it was released in 1977, the development had cost about US$100 million.

Launch and runaway success

The initial price was US$199 with a library of 9 titles. In a play to compete directly with the Channel F, Atari named the machine the Video Computer System (or VCS for short), as the Channel F was at that point known as the VES, for Video Entertainment System. The 2600 was also rebadged as the Sears Video Arcade and sold through Sears-Roebuck stores. When Fairchild learned of Atari's naming, they quickly changed the name of their system to become the Channel F. However, both systems were now in the midst of a vicious round of price-cutting: PONG clones made obsolete by these newer and more powerful machines sold off their boxes to discounters for ever-lower prices. Soon many of the clone companies were out of business, and both Fairchild and Atari were selling to a public that was completely burnt out on PONG. In 1977, Atari sold only 250,000 VCSs. In 1978, only 550,000 units from a production run of 800,000 were sold, requiring further financial support from Warner to cover losses. This led directly to the disagreements that caused Atari founder Nolan Bushnell to leave the company in 1978.[original research?]

Once the public realized it was possible to play video games other than PONG, and programmers learned how to push its hardware's capabilities, the 2600 gained popularity. By this point, Fairchild had given up, thinking video games were a passed fad--thereby handing the entire quickly growing market to Atari. By 1979, the 2600 was the best-selling Christmas present (and console), mainly because of its exclusive content, and a million were sold that year.

File:A2600 Space Invaders.png
Atari 2600 Space Invaders (1980).

Atari then licensed the smash arcade hit Space Invaders by Taito, which greatly increased the unit's popularity when it was released in May 1980, doubling sales again to over 2 million units. The 2600 and its cartridges were the main factor behind Atari grossing more than $2 billion in profits in 1980. Sales then doubled again for the next two years, with almost 8 million units selling in 1982.

During this period, Atari expanded the 2600 family with two other compatible consoles. They designed the Atari 2700, a wireless version of the console that was never released because of a design flaw.[citation needed] The company also built a sleeker version of the machine dubbed the Atari 2800 to sell directly to the Japanese market in early 1983, but it suffered from competition with the newly released Nintendo Famicom.

Decline

During this period, Atari continued to grow until it had one of the largest R&D divisions in Silicon Valley. They spent much of their R&D budget on projects that seemed rather out of place at a video game (or even home computer) company; many of these projects never saw the light of day. Meanwhile, several attempts to bring out newer consoles failed for one reason or another, although their home computer systems, the Atari 8-bit family, sold reasonably, if not spectacularly. Warner was more than happy anyway, as it seemed to have no end to the sales of the 2600, and Atari was responsible for over half of the company's income.

File:PacManCrt260007052004.jpg
2600 Pac Man cartridge

The programmers of many of Atari's biggest hits grew disgruntled with the company for not crediting game developers. For example, Rick Mauer, the programmer of Atari 2600 Space Invaders, received no credit and made only $11,000 for his efforts, in spite of the cartridge grossing more than $100 million in sales. Most notably, Warren Robinett, the lead programmer of Adventure, in protest against Atari's anonymity policy, hid his name in a secret room within the game. This was one of the first "Easter eggs"—a hidden treat or in-joke—a practice which continues in software development to this day. Many other programmers left the company and formed their own independent software companies. The most prominent and longest-lasting of these third-party developers was Activision, founded in 1980, whose titles quickly became more popular than those of Atari itself. Atari attempted to block third-party development for the 2600 in court but failed, and soon other publishers, such as Imagic and Coleco, entered the market. Atari suffered from an image problem when a company named Mystique produced a number of pornographic games for the 2600. The most notorious of these, Custer's Revenge, caused a large number of protests from women's and Native American groups. Atari sued Mystique in court over the release of the game.

Atari continued to scoop up licenses during the shelf life of the 2600, the most prominent of which included Pac-Man and E.T. Public disappointment with these two titles and the market saturation of bad third-party titles are cited as big reasons for the video game crash of 1983. Suddenly, Atari's growth meant it was losing massive amounts of money during the crash, at one point about $10,000 a day. Warner quickly grew tired of supporting the now-headless company, and started looking for buyers in 1984.

The console that refused to die

Atari 2600 in its 1986 cost-reduced version, also known as the "2600 Jr."

Although not formally discontinued, the 2600 was de-emphasized for two years after Warner's 1984 sale of Atari's Consumer Division to Commodore Business Machines founder Jack Tramiel, who wanted to concentrate on home computers. In 1986, a new version of the 2600 was released (although it was planned for release two years earlier). The new redesigned version of the 2600, unofficially referred to as the 2600 Jr., featured a smaller cost-reduced form factor with a modernized Atari 7800-like appearance. The redesigned 2600 was advertised as a budget gaming system (under $50) that had the ability to run a large collection of classic games. With its introduction came a resurgence in software development both from Atari and from third parties. The Atari 2600 continued to sell in the USA and Europe until 1990, and in Asia until the early 1990s. Over its lifetime, an estimated 25 million units were shipped, and its video game library reportedly numbers more than 900 titles with commercial games released released for this system all the way until 1991. In Brazil, the console became extremely popular in the mid-1980s. The Atari 2600 was officially retired by Atari on January 1, 1992, making it the longest-lived home video game console in US game history. It had a lifespan of 14 years and 2 months, nearly three times the typical lifespan of a console.

At the turn of the millennium, 25-years-plus after the launch of the Atari 2600, new homebrew games for the system are still made and sold by hobbyists with several new titles available each year. The console and its old and new games are very popular with collectors because of its significant impact on video game and consumer electronics history and also due to its nostalgic value for many people. In addition, modern Atari 2600 clones remain on the market. One example is the Atari Classics 10-in-1 TV Game, manufactured by Jakks Pacific, which simulates the 2600 console, and includes converted versions of 10 games into a single Atari-brand-look-a-like joystick with composite video outputs for connecting directly to modern televisions or VCRs. Another is the TV Boy, which includes 127 games in an enlarged joypad.

Additionally, Benjamin Heckendorn has created several different versions of a portable 2600, created by cutting apart full-sized vintage units, adding screens and putting them into new enclosures.

The Atari Flashback 2 console, released in 2005, contains 40 games (with four more programs unlockable by a cheat code). The console implements the original 2600 architecture and can be modified to play original 2600 cartridges by adding a cartridge header, and is compatible with original 2600 controllers.

The Atari insignia has become an iconic pop cultural logo.

Atari 2600 in music

In the early 2000s Paul Slocum developed a cart called AtariSynth for the Atari 2600. The AtariSynth allows the user to turn an Atari 2600 into a 2 voice synth/drum machine. Many bands like 8 Bit Weapon, Bud Mevlin, The Squigs, as well as Paul's own band TreeWave, use the synthcart to make modern music on the Atari 2600 today.[citation needed]

Emulation

Atari 2600 emulation is available for most major operating systems and is now very accurate. Despite the relative simplicity of the 2600 system, it is not a simple system to emulate. While it does not require lots of computational power to emulate the 2600, it is hard to accurately do so. For example, because of the lack of a frame buffer (discussed below), 2600 emulators must not only emulate the console, but the television as well. Due to the longevity of the system, many 2600 games used undocumented features, and even exploited bugs in the hardware and firmware to harness the most of the system, doing things even the original designers would deem impossible (a notable example is the starfield of the game Cosmic Ark). It took some time for the emulator programmers to mature their software to properly emulate the undocumented features, bugs and quirks of the system.

The MESS emulator supports recording and playing back of Atari 2600 emulation sessions. The Home Action Replay Page (aka HARP) allows Atari 2600 users to archive their favorite play sessions of the Atari 2600 system and its games.

Some well known Atari 2600 emulators today are:

  • Stella - An open source, multiplatform, very popular emulator (Windows, Mac OS X, Linux) .
  • z26 - Another open source, multiplatform, very popular and customizable emulator (Windows, MS-DOS, Linux)
  • PC Atari Emulator - Easy to use, very fast and popular emulator (Windows, MS-DOS). Handles the Cosmic Ark starfield effect correctly.
  • MESS - the multi system emulator that supports all old Atari console systems
  • The Pocket VCS - PPC - Easy to use, very fast and popular emulator (Windows CE).

Description

2600 game cartridge innards: basically a circuit board with a ROM chip (center) and dual-sided 24-pin edge connector (bottom).

The basic layout of the 2600 is fairly similar to most consoles and home computers of the era. The CPU was the MOS Technology 6507, a cut-down version of the 6502, running at 1.19 MHz in the 2600. The 6507 included fewer memory address pins — 13 instead of 16 — and no external interrupts to fit into a smaller 28-pin package. Smaller packaging was, and still is, an important factor in overall system cost, and since memory was very expensive at the time, the 6507's small 8 KB of maximum external memory space wasn't going to be used up anyway. In fact, memory was so expensive they couldn't imagine using up even 4K, and when they got a deal on 24-pin connectors for the cartridge socket, they were only too happy to thereby limit the games to 4K.[2] Later games got around this limitation with bank switching.

The console had only 128 bytes of RAM for runtime data that included the call stack and the state of the game world. There was no frame buffer, as the necessary RAM would have been too expensive. Instead the video device had two bitmapped sprites, two one-line "missile" sprites, a one-pixel "ball," and a "playfield" that was drawn by writing a bit pattern for each line into a register just before the television scanned that line. As each line was scanned, a game had to identify the non-sprite objects that overlapped the next line, assemble the appropriate bit patterns to draw for those objects, and write the pattern into the register. By default the right side of the screen was a duplicate of the left; to control it separately, the software had to modify the patterns as the scan line was drawn. After the controller scanned the last active line, a more leisurely vertical blanking interval began, during which the game could process input and update the positions and states of objects in the world. Any mistake in timing produced visual artifacts, a problem programmers called racing the beam.

The video hardware gave the 2600 a reputation as one of the most complex machines in the world to program, but those programmers who understood it realized that such direct control over the video picture was also a source of flexibility. One advantage the 2600 had over more powerful competitors such as the ColecoVision was that the 2600 had no protection against altering settings in mid-line. For example, although each sprite nominally had only one color, it was possible to color the rows differently by changing the sprite's color as it was drawn. If the two hardware sprites were not enough for a game, a developer could share one sprite among several objects (as with the ghosts in Pac-Man) or draw software sprites, which was only a little more difficult than drawing a fixed playfield. The Pitfall! screen shot below demonstrates some of these tricks: the player is a multi-color sprite, one sprite is multiplexed for the logs and the scorpion, and the swinging vine is drawn by software. Despite the hardware limitations, many Atari 2600 games had a lot of action on the screen, creating an engaging experience.

Notable games

A comprehensive alphabetical list of games is given in the article List of Atari 2600 games

Technical specifications

Console hardware

  • CPU: 1.19 MHz MOS Technology 6507
  • Audio + Video processor: TIA. 160 x ~192 pixel, 128 colors (128 on screen. Max 4 per line without tricks), 2 channel mono sound.
  • RAM (within a MOS Technology RIOT chip): 128 bytes (additional RAM may be included in the game cartridges)
  • ROM (game cartridges): 4 KiB maximum capacity (32 KiB+ with bank switching)
  • Input (controlled by MOS RIOT):
    • Two screwless DE-9[3] controller ports, for single-button joysticks, paddles, "trakballs", "driving controllers", 12-key "keyboard controllers" (0–9, #, and *) and third party controllers with additional functions
    • Six switches (original version): Power on/off, TV signal (B/W or Color), Difficulty for each player (called A and B), Select, and Reset. Except for the power switch, games could (and did) assign other meanings to the switches. On later models the difficulty switches were miniaturized and moved to the back of the unit.
  • Output: B/W or Color TV picture and sound signal through RCA connector (NTSC, PAL or SECAM, depending on region; game cartridges are exchangeable between NTSC and PAL/SECAM machines, but this will result in wrong or missing colors and often a rolling picture.)

Third-party peripherals

  • Gameline Master Module, a modem allowing downloads of games from an extensive catalog which could be playable for a limited amount of time.

References and notes

  • Perry, Tekla; Wallich, Paul. "Design case history: the Atari Video Computer System". IEEE Spectrum. March 1983.
  1. ^ The first game console to use exchangeable plug-in cartridges was the Fairchild Channel F, and the RCA Studio II also predates the 2600. However, it was the Atari 2600 that made the plug-in concept popular among the game-playing public.
  2. ^ The cartridge connector's 24 pins were allocated to one supply voltage line, two ground lines, 8 data lines, and 13 address lines. However, the uppermost address line was used as a so-called chip select for the cartridge's ROM chip, leaving only 12 address lines for the chip's game program. Thus, without special "hardware tricks" built into the cartridge, an Atari 2600 game could occupy a maximum address space of 4K.
  3. ^ The screwless DE-9 controller ports subsequently became the mechanical/electrical de facto standard for game controllers in the 8-bit and early 16-bit era and were used in most subsequent Atari and Commodore consoles and home computers, among many others including the Sega Genesis.

Also the Atari joysticks could be used in MSX and several Japanese computers. It is possible to use the joysticks in Sega systems like the Sega Master System or Sega Genesis in games that only require one button.

See also

(*Joe Decuir was one of the designers of the Atari 2600 and the Atari 400/800 SIO bus. Later he worked on the design of the USB interface)