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Atari 7800
Atari 7800 System
Manufacturer Atari Corporation
Type Video game console
Generation Third generation (8-bit era)
Retail availability United States May 1984 [1](original release)
United StatesJanuary 1986 (re-release)
European Union 1987
Introductory price US$140
Media ROM cartridge
CPU Atari SALLY 6502 ("6502C") clocked at 1.19-1.79MHz,
Memory 4KB RAM, 4KB BIOS ROM, 48KB Cartridge ROM Space
Display 160x240, 320x240 (160x288/320x288 if PAL), 25 on-screen colours out of possible 256
Backward
compatibility
Atari 2600
Predecessor Atari 5200
Successor Atari XE Game System

The Atari 7800 ProSystem, or simply the Atari 7800, is a video game console re-released by Atari Corporation in January 1986. The original release had occurred two years earlier under Atari Inc. The 7800 was designed to replace Atari Inc.'s unsuccessful Atari 5200 and later to re-establish Atari Corp.'s market supremacy against Nintendo and Sega. With this system, Atari Inc. addressed all the shortcomings of the Atari 5200: it had simple digital joysticks; it was almost fully backward-compatible with the Atari 2600; and it was affordable (originally priced at US$140).

Contents

Introduction

The Atari 7800 ProSystem was the first game system from Atari Inc. designed by an outside company, General Computer Corporation (GCC). The system had been designed in 1983 through 1984 with an intended mass market rollout in June 1984, but was canceled shortly thereafter due to the sale of the company to Tramiel Technology Ltd on July 2, 1984. The project was originally called the Atari 3600, though was later renamed the Atari 7800.

Several key factors influenced the design of the 7800. First, Atari had been facing mounting pressure from the ColecoVision, which boasted graphics that more closely mirrored arcade games of the time than Atari’s reigning 2600 VCS system. Second, the Atari 5200 (the original intended successor to the Atari 2600 VCS) had been widely criticized for not being able to play Atari 2600 VCS games and for the poor quality of its analog joysticks. Finally, dropping prices of home computers like the Commodore 64 had caused many to believe that buying a home computer was a better investment because it provided more detailed gameplay and could be used for other purposes such as word processing.

Previous game consoles sometimes had a difficult time replicating the arcade experience in home versions of popular arcade games. In particular, home versions of arcade games sometimes had problems with flickering and slow down when more than a few moving objects appeared on the screen at once. GCC, which had a background in creating arcade games, designed their new system with a graphical architecture similar to arcade machines of the time. The 7800 featured the ability to move around a tremendous amount of objects (75-to-100) that far exceeded previous consoles. Powering the system was an Atari SALLY 6502 (Atari's slightly custom 6502, sometimes described as a "6502C") processor running at 1.79 MHz, similar to the processor found in home computers (Atari 8-bit, Apple II, Commodore 64) and other consoles (Atari 5200 and Nintendo Entertainment System).

In response to the criticisms of the Atari 5200, the Atari 7800 could play almost all Atari 2600 games out of the box, without the need for an adapter. In addition, it featured a return to a digital controller.

To address the concerns of parents that home computers were a better investment than consoles, the system was designed to be upgraded to a full-fledged home computer. A keyboard was developed, and the keyboard had an expansion port (which was the SIO port from Atari's 8-bit computer line, though the 7800 could not run Atari computer programs) allowed for the addition of peripherals such as disk drives and printers.

To enhance the gaming experience further, GCC had also designed a 'high score cartridge,' a battery-backed RAM cartridge designed for storing game scores. On the side of the 7800 was an expansion port, reportedly for a planned connection with a laserdisc player.

Original 1984 release

The 7800 was initially released in southern California in June 1984, following an announcement on May 21, 1984 at the Summer Consumer Electronics Show (CES). Thirteen games were announced for the systems launch, including Ms. Pac-Man, Pole Position II, Centipede, Joust, Dig Dug, Desert Falcon, Robotron: 2084, Galaga, Xevious, Food Fight, Ballblazer, Rescue on Fractalus!, and Track and Field. Atari was a sponsor of the 1984 Summer Olympics and planned to push the 7800 aggressively in time for Christmas that year.

One month later, Warner Communications sold Atari's Consumer Division to Jack Tramiel. All projects were halted during an initial evaluation period.

The Atari 7800 languished on warehouse shelves until it was re-introduced in January 1986 after strong 2600 sales the previous Christmas.[2]

Atari's launch of the 7800 under Tramiel was far more subdued than Warner had planned for the system in 1984 with a marketing budget of just $300,000. Additionally, the keyboard and high score cartridge were canceled, the expansion port was removed from later production runs of the system and, in lieu of new titles, the system was launched with titles intended for the 7800's debut in 1984.

Graphics

The strengths and weaknesses of the 7800's graphics are often debated. The graphics are generated by a custom Graphics Processing Unit called MARIA (a name chosen to represent its succession from the Atari 2600's graphics and sound chip, TIA ... TIA-MARIA). MARIA is very different from other second and third generation consoles, which made it more difficult for game programmers to make the transition. Instead of a limited number of hardware sprites, the MARIA allows for a much larger number of sprites described in a list of display lists. Each display list contains sprite entries with pointers to graphics data, color information, and horizontal positioning. The same display list is used for multiple rasters with the pointers being automatically adjusted. However, managing and displaying a large number of sprites required much more CPU time (both directly and indirectly since the MARIA would halt the CPU when drawing sprites) than consoles with hardware sprites and backgrounds.

MARIA has a number of different graphics modes which are either 160 pixels wide or 320 pixels wide. While the 320 pixel modes theoretically enable the 7800 to create games at higher resolution than the 256 pixel wide graphics found in the Nintendo Entertainment System and Sega Master System, the intense processing demands of MARIA typically meant that programmers created their games using the lower 160 pixel modes.

The 7800 features a broad (for its time) palette of 256 colors. Depending on various parameters, each individual sprite can use from 1 to 12 colors, with 3 colors (plus a 4th "transparency" color) being the most common. In this format, the sprite is referenced to one of 8 palettes, where each palette holds 3 assignable colors. There is also an assignable background color, which will be visible wherever another object has not covered it up. In total the system can utilize 25 colors on a scanline at one time.[3]

The graphics resolution, color palette assignments, and background color can be adjusted in between scanlines. Although it is a more advanced programming technique, this isn't really a "trick". The designers deliberately included this feature, and documented its use in the original 1983 "Atari 3600 Software Guide".[4] Games often used this feature to render high resolution text in one area of the screen, while displaying more colorful graphics with less resolution in the gameplay area. Demos also exist which use this feature to place all 256 colors on the screen at the same time.

The MARIA’s approach had advantages and disadvantages when it came to generating graphics in software during the lifespan of the 7800. It excelled at moving around large numbers of sprites on a static screen without the screen flickering that plagued other 8-bit systems. Its flexible design enabled it to play games which used display list manipulation to generate a pseudo 3D appearance such as Ballblazer (1987) and F-18 Hornet (1988). While side-scrolling games in the vein of Super Mario Bros. are possible on the system (1990's Scrapyard Dog is the best example), it is significantly harder to develop such a title than on a tile-based system such as the Nintendo Entertainment System.

Sound

A common criticism of the 7800 regards its use of the TIA to provide 2-channel sound effects and music, resulting in sound quality that is virtually identical to the Atari 2600 VCS from 1977. While the inclusion of 2600 hardware is required to maintain compatibility with the older system, this drove up production costs and reduced available space on the 7800’s motherboard. As such, the 7800 does not include additional hardware for generating sound as it does with graphics and the sound hardware is considered the weakest part of the system.

To compensate for this, GCC’s engineers allowed games to include a POKEY audio chip in the cartridge which substantially improved the audio quality. To ensure software developers had an economical means of producing better sound than TIA, GCC had originally planned to make a low-cost, high performance sound chip, GUMBY, which could also be placed in 7800 cartridges to enhance its sound capabilities further. This project was cancelled when Atari was sold to Jack Tramiel.

Despite having the capability to support sound chips in cartridges, almost no 7800 cartridges feature POKEY hardware for enhanced sound. Ballblazer, released in 1987, uses the POKEY to generate all music and sound effects. Similarly, Commando, released in 1989, uses a POKEY to generate in-game music while the TIA generates the game's sound effects for a total of 6 channels of sound.

Lockout features

Following the debate over Custer's Revenge, an Atari 2600 VCS title with adult themes, Atari had concerns over similar adult titles finding their way onto the 7800 and displaying adult graphics on the significantly improved graphics of the MARIA chip. To combat this, they included a digital signature protection method which prevented unauthorized 7800 games from being played on the system.

When a cartridge was inserted into the system, the 7800 BIOS included code which would generate a digital signature of the cartridge ROM and compare it to the signature stored on the cartridge. If a correct signature was located on the cartridge, the 7800 would operate in 7800 mode, granting the game access to MARIA and other features. If a signature was not located, the 7800 remained in 2600 mode and MARIA was unavailable. All 7800 games released in North America had to be digitally signed by Atari. This digital signature code is not present in PAL 7800s, which use various heuristics to detect 2600 cartridges, due to export restrictions.

Comparison with the Atari 2600 VCS

The Atari 7800 differs from the 2600 in several key areas. It features a full Atari SALLY 6502 processor whereas the 2600 VCS has a stripped down 6507 processor running at a slower speed. It has additional RAM (Random Access Memory) and the ability to access more cartridge data at one time than the 2600. The most substantial difference, however, is a graphics architecture which differs markedly from either the Atari 2600 VCS or Atari’s 8-bit line of computers.

The 7800's compatibility with the Atari 2600 is made possible by including many of the same chips used in the Atari 2600. When operating in “2600” mode to play Atari 2600 titles, the 7800 uses a Television Interface Adapter (TIA) chip to generate graphics and sound. The processor is slowed to 1.19 MHz, enabling the 7800 to mirror the performance of the 2600’s stripped-down 6507 processor. RAM is limited to 128 bytes found in the RIOT and game data is accessed in 4K blocks.

When in “7800” mode (signified by the appearance of the full screen Atari logo), the graphics are generated entirely by the MARIA graphics processing unit, all system RAM is available and game data is accessed in larger 48K blocks. The system’s SALLY 6502 runs at its normal 1.79 MHz instead of the reduced speed of 2600 mode. The 2600 chips are used in 7800 mode to generate sound as well as switch and controller interfaces.

Software library

While the 7800 can actually play hundreds of titles due to its compatibility with the Atari 2600, there was limited third party support for the 7800 and less than 100 titles were specifically designed for it.

System launch and initial titles

The 7800 debuted with "pre-crash" titles that were originally intended for the systems launch in 1984, games which seemed dated in comparison to the Nintendo Entertainment System by the time of its release in 1986. Atari responded by beginning development on new 7800 titles but their investment and production was very limited. Numerous 7800 games were quickly rushed to market resulting in games which were unpolished, lacking in features and underpowered in comparison to their Nintendo counterparts.

In response to criticism about the lack of depth to their games, Atari began to use bankswitching by 1988, releasing 64K and later 128K (1 megabit) titles which were comparable to both Nintendo Entertainment System and Sega Master System games. By the end of the system’s life cycle, most games were 128K in size, with a few being 144K. While the system was certainly capable of playing even larger games (4 megabit and beyond) no games of that size were developed.

Availability of current arcade conversions

At the time, a key driver for success with a home console was the number of home conversions it had of popular arcade games. This had been a primary reason for the success of the Atari 2600 VCS against systems like the Intellivision.

During the Atari 7800’s life cycle, Atari found themselves struggling to get developers to create 7800 versions of then-popular arcade titles because of a controversial policy employed by Nintendo. When Nintendo revived the industry, they signed up software development companies to create NES games under a strict license agreement which imposed serious restrictions on what they were allowed to do. One of the key clauses was that companies who made Nintendo games were not allowed to make that game on a competing system for a period of two years. Because of the market success of the NES, companies chose to develop for it first and were thus barred from developing the same games on competing systems for two years.

The software libraries of the Atari 7800 and Sega Master System suffered tremendously as a result. The 7800 fared even worse due to the fact that Sega could draw from their own library of arcade hits in supporting the Master System (Atari’s arcade division had been spun off into a separate company in 1984). The Atari 7800 was often forced to fill the void with either computer conversions or original titles, to varying degrees of success.

Some NES titles were developed by companies who had licensed their title from a different arcade manufacturer. While the creator of the NES version would be restricted from making a competitive version of an NES game, the original arcade copyright holder was not precluded from licensing out rights for a home version of an arcade game to multiple systems. Through this loophole, Atari 7800 conversions of Mario Bros., Double Dragon, Commando, Rampage, Xenophobe, Ikari Warriors and Kung Fu Master were licensed and developed.

Exclusive content and missing genres

A primary criticism of the Atari 7800’s library is that many games on the system were also available elsewhere. Most of the original lineup of games had already appeared on either Atari’s 2600, 5200, or 8-bit computers. This practice continued after Tramel Technology Ltd's takeover of Atari as 2600 and XE Game System versions (not ports) of 7800 games would be produced as well. Later, many titles exclusive to the 7800 would also appear on the Atari Lynx, though, again, not direct ports of the 7800 version.

The Atari 7800’s small library lacked key genres (role playing games), poorly represented ones(sports games), or had a disproportionate glut of specific ones (flight simulators).

Third-party software support

Third party development for the 7800 was limited as most game companies were locked into exlusivity agreements with Nintendo for the NES. Eleven titles were developed and sold by three third-party companies under their own labels for the 7800 (Absolute Entertainment, Activision, and Froggo) with the rest published by Atari themselves. However, most Atari development was contracted out.

Peripherals

The gamepad of the Atari 7800.

Unlike the NES or Sega Master System, there were few peripherals for the 7800. The most notable peripheral was the XG-1 lightgun, which came bundled with the Atari XE Game System. The XG-1 was fully compatible with the 7800 and was sold separately for other Atari systems. Atari released four 7800 light gun games: Alien Brigade, Crossbow, Meltdown, and Barnyard Blaster.

In response to criticism over ergonomic issues in the 7800’s Pro-Line controllers, Atari later released joypad controllers with European 7800s, which were similar in style to controllers found on Nintendo and Sega Systems.

The 7800 included an expansion port which would have allowed for the addition of a computer keyboard, connection to laserdisc players to play laserdisc games and other peripherals.

A High Score cartridge was designed to save scores for up to 65 separate games. [In 1999, Curt Vendel with a schematic and ROM code from Gary Rubio—the former Atari liaison to GCC on the Atari 7800 project, reproduced a new run of Atari 7800 high-score cartridges.]

A dual joystick holder was designed for games like Robotron 2084 and future games like Battlezone and others, but not produced.[citation needed]

Market performance

The Atari 7800 remained officially active between 1986 and 1991. On January 1, 1992, Atari Corp. formally announced that production of the Atari 7800, the Atari 2600, the Atari 8-bit computer line, and the Atari XE Game System would cease. By the time of the cancellation, Nintendo's NES dominated the North American market, controlling 80% while Atari Corp. controlled just 12%.[5]

Despite trailing the Nintendo Entertainment System in terms of number of units sold, the 7800 was a profitable enterprise for Atari Corp., benefiting largely from Atari’s name and the system's 2600 compatibility. Profits were strong due to low investment in game development and marketing. Nonetheless, the 7800 failed to help Atari regain its dominance in the videogame industry.

Homebrew community and emulation

When emulators of 1980s video game consoles began to appear on home computers in the late 1990s, the Atari 7800 was one of the last to be emulated. The lack of awareness of the system, the lack of understanding of the hardware, and fears about the digital signature lockout initially caused concerns. Since that time, however, the 7800 has been emulated successfully and is now common on emulation sites. One such program is ProSystem, written in C/C++ for the Microsoft Windows operating system.[6] It uses Windows API and DirectX to display what it emulates in both PAL and NTSC.

The digital signature long prevented homebrew games from being developed until the original encryption generating software was discovered. When the original digital signature generating software was turned over to the Atari community, development of new Atari 7800 titles began. In addition, the Atari community has slowly uncovered the original 7800 development tools and released them into the public domain. New tools, documentation, source code and utilities for development have since been created which has sponsored additional homebrew development. Several new commercial Atari 7800 titles such as Beef Drop, B*nQ, Pac Man Collection, Combat 1990, Santa Simon, and Space War have been created and released.

Perhaps the most interesting recent development was the creation of the Cuttle Cart II, a device that allowed the Atari 7800 to read MMC cards containing binary files of Atari 7800 programs. The Cuttle Cart II has enabled more people to play the entire 2600 and 7800 library on an original system as well as binaries of unreleased games and new homebrew titles.

The Cuttle Cart II was a success by homebrew standards, selling out both production runs and commanding high prices on Ebay.

New mainstream releases

In 2004, Atari (now owned by Infogrames) released the first Atari Flashback console. This system resembled a miniature Atari 7800 and joysticks and had 20 built in games (five 7800 and fifteen 2600 titles). While the unit sold well, it was controversial among Atari fans. Atari had given the engineering firm, Legacy Engineering, extremely limited development timelines. The firm was forced to build the Flashback using NES-On-A-Chip hardware instead of recreating the Atari 7800 hardware. As a result, the Flashback has been criticized for failing to properly replicate the actual Atari gaming experience.

Legacy Engineering was later commissioned to create another 7800 project that never made it to market. A reseller with millions of unsold Atari 2600 and 7800 games acquired from the Tramiels looked into remaking the system and bringing it to market as a way for new customers to play old Atari games. The project was cancelled after prototypes were made.

Unreleased games

As with most game consoles, there were many more games in development for the 7800 than were actually released. However, very few prototypes have been located, due to Tramiel Atari’s reluctance to make them in the first place. Atari 7800 prototypes tend to be highly coveted by collectors, often fetching hundreds of dollars when sold. Some collectors are unwilling to share the rare items publicly as doing so risks decreasing the value of their prototypes.

Nonetheless, some unreleased Atari 7800 games, as well as early versions of released games have been released to the public. A few have been manufactured and sold.

These include

  • Klax (Programmed by Blue Sky Software). The game was nearly completed when canceled. For years, it was traded privately until a ROM was made available to the general public. Later, the developer appeared to create additional levels for the community.
  • Gato (Programmed by Ibid Inc Software). Released on the XE Game System, an Atari 7800 version was started but not completed beyond a simple demo.
  • Missing in Action (Programmed by Sculptured Software for TNT Games). A side scrolling adventure that was about 85% complete when cancelled. The game is mostly playable with some later collision detection issues requiring cheats to get past.
  • Pit-Fighter (Programmed by Imagitec Design). An early demo of the game has been found, with crude graphics, no sound and poor collision detection.
  • Rescue on Fractalus! (Programmed by GCC). A conversion of the popular computer game was released by GCC in 2004. The game was partially complete with a running engine but no enemies.
  • Other 7800 games remain lost, despite indications that development occurred. The most notable of these are Skyfox (shown on the back of the original system box) and Electrocop (artwork has since been uncovered).

Engineering Notes list Tempest as a game that was between 15–20% completed for the Atari 7800, no code to date has been found. The Atari Museum located and posted unreleased box art and notes for a 7800 version of Crystal Castles. No code to date has been found for that game either. Atari's earlier 7800 games listing showed Millipede as one of the games in the line up, however it does not appear that it was ever started or worked on.

Source Code Release

Source code to 13 games, as well as the OS and development tools (for the Atari ST computer system) were discovered in a dumpster behind the Atari building in Sunnyvale, California.[7] Commented assembly language source code was made available for Centipede, Commando, Crossbow, Desert Falcon, Dig Dug, Food Fight, Galaga, Hat Trick, Joust, Ms. Pac-Man, Super Stunt Cycle, Robotron: 2084 and Xevious game titles.[8]

Technical specifications

  • CPU: Atari SALLY 6502 ("6502C")
    • Speed: 1.79 MHz, drops to 1.19 MHz when the TIA or RIOT chips are accessed
    • (note: Unlike a standard 6502, SALLY can be halted to allow other devices to control the bus)
  • RAM: 4 KB (2 6116 2Kx8 RAM ICs)
  • ROM: built in 4 KB BIOS ROM, 48 KB Cartridge ROM space without bankswitching
  • Graphics: MARIA custom graphics controller
    • 160x240 (160x288 PAL) resolution or 320x240/288 resolution
    • 25 color palette out of 256 colors (16 hues * 16 luma), different graphics modes restricted the number of usable colors and the number of colors per sprite
    • Direct Memory Access (DMA)
    • Graphics clock: 7.16 MHz
  • I/O: Joystick and console switch IO handled byte 6532 RIOT and TIA
  • Ports: 2 joystick ports, 1 cartridge port, 1 expansion connector, power in, RF output
  • Sound: TIA video and sound chip, same as the 2600. Only the sound is used in 7800 games. Both video and sound are used in 2600 games.
    • Optional POKEY sound chip on cartridge for improved sounds.

System revisions

Prototypes:

  • Atari 3600, original model number
  • Atari CX-9000 Video Computer System

Production:

  • Atari CX7800, two joystick ports on lower front panel. Side expansion port for upgrades and add-ons. Bundled accessories included two CX24 Pro-Line joysticks, AC adapter, switchbox, RCA connecting cable, and Pole Position II cartridge.
  • Atari CX7800, second revision. Slightly revised motherboard, added an additional timing circuit. Expansion port connector removed from motherboard but is still etched. Shell has indentation of where expansion port was to be.
  • Atari CX7800, third revision. Same as above but with only a small blemish on the shell where the expansion port was.

See also

References

External links


Strategy wiki

Up to date as of January 23, 2010
(Redirected to Category:Atari 7800 article)

From StrategyWiki, the free strategy guide and walkthrough wiki

Atari 7800
The console image for Atari 7800.
Manufacturer Atari
Active 19861992
Total Games 62 (33 present)
← Atari 5200 (none) →

The Atari 7800 was released by Atari in 1986 (a test market occurred in 1984). The 7800 was designed to replace the failed Atari 5200 shortly after the video game market crash of 1983 and was supposed to re-establish Atari's market supremacy. Atari learned from their mistakes with the 5200 and used digital joysticks, included full software compatibility with the Atari 2600, and released the 7800 with an affordable price.

The 7800 was also the first game system from Atari which was designed by an outside company (by the General Computer Corporation, future consoles designed outside the company were the Atari Lynx and the Atari Jaguar). The 7800 was upgraded to be a full-fledged home computer. A keyboard was developed, which included an SIO port so peripherals like disk drives and printers could be used. GCC also designed a high score cartridge, which was a battery-backed RAM cart used to store high scores taken from games.

Atari manufactured none of these accessories, but in 1987, the Atari XEGS was released, which came with a light gun, called the XG-1. The XG-1 was fully compatible with the 7800 and the 2600, and Atari released four games on the 7800 that utilized it.

The 7800 was test-marketed in southern California in June 1984. One month later, Warner Communications sold Atari to Jack Tramiel, who wanted the company to stay away from the video game business. He abandoned all projects related to video games and decided to focus on Atari's existing computer line in order to begin development of the new 16-bit computer line. The 7800 was re-introduced in 1986 due to Nintendo's success with the NES, proving the video game market was still alive. However, Nintendo had more than 90% of the market cornered, with rival Sega's Master System taking up the rest.

The 7800 faced the severe software drought that would become the mark of all Atari consoles sold after the video game crash. Relatively few titles were released by Atari, many of them lacking, or even games that were released on previous Atari systems. Atari focused no effort finding or recruiting third party developers, which led to a rapid decrease in interest. On January 1, 1992, Atari formally announced abandonment of the Atari 7800, in addition to the Atari 2600 and the Atari 8-bit computer line, including the Atari XE Game System.


Gaming

Up to date as of January 31, 2010

From Wikia Gaming, your source for walkthroughs, games, guides, and more!

The Atari 7800 is a video game console released by Atari in June 1986 (a test market release occurred two years earlier). The 7800 was designed to replace the unsuccessful Atari 5200, and re-establish Atari's market supremacy against Nintendo and Sega. With this system, Atari addressed all the shortcomings of the Atari 5200: it had simple digital joysticks; it was almost fully backward-compatible with the Atari 2600; and it was affordable (it was originally priced at US$140).

Contents

Summary

The 7800 was the first game system from Atari designed by an outside company (General Computer Corporation; future consoles designed outside the company included the Atari Lynx and the Atari Jaguar). The system was designed to be upgraded to a full-fledged home computer — a keyboard was developed, and the keyboard had an expansion port (which was the SIO port from Atari's 8-bit computer line) for the addition of peripherals like disk drives and printers (this should not be taken to imply that this computer expansion would have allowed the 7800 to run programs designed for Atari's computers, as the two architectures were entirely different). GCC had also designed a 'high score cartridge,' a battery-backed RAM cart designed for storing game scores. Atari manufactured none of these accessories, and after the initial production run they also eliminated the expansion port (allegedly for connection to a LaserDisc player). In 1987, the Atari XEGS was released and it came with a light gun, called the XG-1. The XG-1 was fully compatible with the 7800 and the 2600, and Atari released four games on the 7800 that utilized this peripheral.

Image:Atari7800.jpg

The 7800 was test-marketed in southern California in June 1984. One month later, Warner Communications sold Atari to Jack Tramiel, who did not want to release a new video game console under his newly formed Atari Corporation. He pulled the plug on all projects related to video games and decided to focus on Atari's existing computer line in order to begin development of the new 16-bit computer line (which appeared as the Atari ST). The 7800 was re-introduced at the end of 1986 after the success of the NES proved that the video game market was still viable. Unfortunately, by the time the 7800 made it to market, the NES had 90% of the market cornered and the rival Sega Master System had most of what was left.

The 7800's technical superiority is still debated today. According to a 2003 interview with Leonard Tramiel, the Atari 7800 was essentially "a 2600 with some things put into hardware that were done in software on the 2600". [1] Although this view is held by many, the truth is the 7800 shares little architecturally with the 2600. (In fact, Tramiel's statement is more applicable to the Atari 5200, where the ANTIC drives the GTIA to produce graphics like a 2600 game's kernel drives the 2600 TIA.) Compatibility with the Atari 2600 is handled in the same way the Genesis provides compatibility with the Sega Master System - by including the same chips used in the Atari 2600. When in 7800 mode, the 2600 chips are used for sound (a cost cutting measure) and the switch and controller interfaces; 7800 graphics are completely generated by the MARIA GPU. The designers allowed games (notably ports from the Atari 400/800 computer line) to include a POKEY audio chip in the cartridge. Only two originally released games, Ballblazer and Commando, used the POKEY chip.

The MARIA GPU is very different from other second and third generation consoles, which made it more difficult for game programmers to make the transition. Instead of a limited number of hardware sprites, the MARIA allows for a much larger number of sprites described in a list of display lists. Each display list contains sprite entries with pointers to graphics data, color information, and horizontal positioning. The same display list is used for multiple rasters with the pointers being automatically adjusted. However, managing and displaying a large number of sprites required much more CPU time (both directly and indirectly since the MARIA would halt the CPU when drawing sprites) than consoles with hardware sprites and backgrounds.

The NTSC 7800 BIOS included code which would generate a digital signature of the cartridge ROM and compare it to the signature stored on the cartridge. This had two benefits. First, it would allow the 7800 to determine whether the cartridge was for the 7800 or the 2600 so the console could be locked into the correct mode. Second, it meant all 7800 games had to be digitally signed by Atari, preventing developers from creating unauthorized games. This digital signature code is not present in PAL 7800s, which use various heuristics to detect 2600 cartridges, due to export restrictions. However, the digital signature long prevented homebrew games from being developed until the original encryption generating software was discovered.

Aftermath

The 7800 faced the severe software drought that would become the mark of all Atari Corp. consoles sold after the video game crash. Relatively few titles were released by Atari, many of them unpolished and lacking in features, or even games that already were in previous Atari systems. And there was virtually no effort by Atari to recruit third party developers, aside from a few titles from Absolute, Activision, and Froggo. In addition, many third party developers were locked into exclusive contracts with Nintendo that specifically forbid development on other consoles. Many of the same practices that gave Atari a huge market share pre-crash came back to haunt them during Atari's late attempt to re-enter the console market with the 7800. These problems caused the 7800 to place a distant third in the market of the time, behind the Sega Master System and NES. On January 1, 1992, Atari formally announced abandonment of the Atari 7800, in addition to the Atari 2600 and the Atari 8-bit computer line, and Atari XE Game System.

Technical specifications

  • CPU: Custom 6502C
    • Speed: 1.79 MHz, drops to 1.19 MHz when the TIA or RIOT chips are accessed
    • (note: This is Atari's custom 6502 known as SALLY which can be halted to allow other devices to control the bus)
  • RAM: 4 kb (2 6116 2Kx8 RAM ICs)
  • ROM: built in 4 kb BIOS ROM, 48 kb Cartridge ROM space without bankswitching
  • Graphics: MARIA custom graphics controller
    • 160x240 (160x288 PAL) resolution or 320x240/288 resolution
    • 25 color palette out of 256 colors (16 hues * 16 luma), different graphics modes restricted the number of usable colors and the number of colors per sprite
    • Direct Memory Access (DMA)
    • Graphics clock: 7.16 MHz
  • I/O: Joystick and console switch IO handled byte 6532 RIOT and TIA
  • Ports: 2 joystick ports, 1 cartridge port, 1 expansion connector, power in, RF output
  • Sound: TIA video and sound chip, same as the 2600. Only the sound is used in 7800 games. Both video and sound are used in 2600 games.
    • Optional POKEY sound chip on cartridge for improved sounds.

System revisions

Prototypes:

  • Atari 3600 - original model number
  • Atari CX-9000 Video Computer System

Production:

  • Atari CX7800 - Two joystick ports on lower front panel. Side expansion port for upgrades and add-ons. Bundled accessories included two CX24 Pro-Line joysticks, AC adapter, switchbox, RCA connecting cable, and Pole Position II cartridge.
  • Atari CX7800 - Second revision. Slightly revised motherboard, added an additional timing circuit. Expansion port connector removed from motherboard but is still etched. Shell has indentation of where expansion port was to be.
  • Atari CX7800 - Third revision. Same as above but with only a small blemish on the shell where the expansion port was.

External links

  • Atari7800.com Institute For Advanced Atari Gaming Studies - Atari History Library & Web Resource
  • Dan B's Atari 7800 Tech Page Tech resource on 7800
  • AtariAge – Comprehensive Atari 7800 Rarity Guide and information
  • Atari 7800 FAQ
  • The Atari 7800 Page
  • Cousin Vinnie's Atari 7800 Panoramic Froo-Froo
  • The Dot Eaters entry featuring the 7800 and its games
  • Atari 7800 Programming mailing list and links to programming information
  • Atari Programming Wiki
  • The Atari Times 7800 Area Game reviews & features
  • HwB - technical info and pinouts


Third-Generation Consoles
Famicom | Sega SG-1000 Mark III | Atari 7800 | Nintendo Entertainment System | Sega Master System | Atari 7800

This article uses material from the "Atari 7800" article on the Gaming wiki at Wikia and is licensed under the Creative Commons Attribution-Share Alike License.

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