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85-460: Color Television Interface Adaptor and Graphic Television Interface Adaptor are names of the chips as stated in the Atari field service manual. Various publications named the chips differently, sometimes using the alternative spelling Adapter or Graphics , or claiming that the "C" in "CTIA" stands for Colleen/Candy and "G" in "GTIA" is for George. Atari had built their first display driver chip,

170-454: A digital-to-analog converter and RF modulator to produce a television display. The conventional way to draw the playfield is to use a bitmap held in a frame buffer , in which each memory location in the frame buffer represents one or more locations on the screen. In the case of the 2600, which normally used a resolution of 160x192 pixels, a frame buffer would need to have at least 160x192/8 = 3840 bytes of memory. Built in an era where RAM

255-600: A membrane keyboard and single internal ROM slot, outsold the Atari 800 by a 2-to-1 margin. Only one cartridge for the 800's right slot was produced by March 1983, and later machines in the series have only one slot. Creative Computing mentioned the Atari machines in an April 1979 overview of the CES show. Calling Atari "the videogame people", it stated they came with "some fantastic educational, entertainment and home applications software". In an August 1979 interview Atari's Peter Rosenthal suggested that demand might be low until

340-533: A 6502B. SALLY was incorporated into late-production 400 and 800 models, all XL/XE models, and the Atari 5200 and Atari 7800 consoles. SALLY adds logic to disable the clock signal, called HALT , which ANTIC uses to shut off the CPU to access the data/address bus. Mirroring the 400/800, two systems were planned, the 1000 with 16 KB and the 1000X with 64 KB, each expandable via a Parallel Bus Interface slot on

425-538: A GTIA chip in CTIA-equipped computers free of charge if the computer was under warranty; otherwise the replacement would cost $ 62.52. GTIA was also mounted in all later Atari XL and XE computers and Atari 5200 consoles. The list below describes CTIA/GTIA's inherent hardware capabilities meaning the intended functionality of the hardware itself, not including results achieved by CPU-serviced interrupts or display kernels driving frequent register changes. CTIA/GTIA

510-419: A higher-end machine known as "Colleen" (named after two Atari secretaries). Atari would market Colleen as a computer and Candy as a game machine or hybrid game console. Colleen includes user-accessible expansion slots for RAM and ROM , two 8 KB ROM cartridge slots, RF and monitor output (including two pins for separate luma and chroma suitable for superior S-Video output) and a full keyboard. Candy

595-617: A key part of the software library. The 1980 first-person space combat simulator Star Raiders is considered the platform's killer app . The Atari 800 was positioned as a high-end model and the 400 as more affordable. The 400 has a pressure-sensitive, spillproof membrane keyboard and initially shipped with a non-upgradable 8 KB of RAM. The 800 has a conventional keyboard, a second cartridge slot, and allows easy RAM upgrades to 48K. Both use identical 6502 CPUs at 1.79 MHz ( 1.77 MHz for PAL versions) and coprocessors ANTIC , POKEY , and CTIA/GTIA . The plug-and-play peripherals use

680-629: A series of registers that can be user-controlled via memory load/store instructions running on the 6502. For example, the GTIA uses a series of registers to select colors for the screen; these colors can be changed by inserting the correct values into its registers, which are mapped into the address space that is visible to the 6502. Some of the coprocessors use data stored in RAM, such as ANTIC's display buffer and display list , and GTIA's Player/Missile ( sprite ) information. The custom hardware features enable

765-461: Is a television interface device with the following features: by part number Atari, Inc. intended to combine functions of the ANTIC and GTIA chips in one integrated circuit to reduce production costs of Atari computers and 5200 consoles. Two such prototype circuits were being developed, however none of them entered production. The Atari 8-bit computers map CTIA/GTIA to the $ D0xx hex page and

850-411: Is no. 'What will it do for me?' That's his major concern. ... why try to scare the consumer off by making it so he or she has to have a double E or be a computer programmer to utilize the full capabilities of a personal computer?" For example, cartridges were expected to make the computers easier to use. To minimize handling of bare circuit boards or chips, as is common with other systems of that period,

935-528: Is solved for many write registers by Operating System Shadow registers implemented in regular RAM as places to store the last value written to registers. Operating System Shadow registers are copied from RAM to the hardware registers during the Vertical Blank. Therefore, any write to hardware registers which have corresponding shadow registers will be overwritten by the value of the Shadow registers during

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1020-536: The Atari Home Computer System , are a series of home computers introduced by Atari, Inc. , in 1979 with the Atari 400 and Atari 800. The architecture is designed around the 8-bit MOS Technology 6502 CPU and three custom coprocessors which provide support for sprites , smooth multidirectional scrolling, four channels of audio, and other features. The graphics and sound are more advanced than most of its contemporaries, and video games are

1105-533: The Atari SIO serial bus , and one of the SIO developers eventually went on to co-patent USB (Universal Serial Bus). The core architecture of the Atari 8-bit computers was reused in the 1982 Atari 5200 game console, but games for the two systems are incompatible. The 400 and 800 were replaced by multiple computers with the same technology and different presentation. The 1200XL was released in early 1983 to supplant

1190-651: The CTIA (the VCS version was the TIA). During the early development period, the home computer era began in earnest with the TRS-80 , PET , and Apple II —what Byte magazine dubbed the "1977 Trinity". Nolan Bushnell sold Atari to Warner Communications for US$ 28 million in 1976 to fund the launch of the VCS. In 1978, Warner hired Ray Kassar to become the CEO of Atari. Kassar said

1275-552: The Federal Communications Commission (FCC) introduced new testing standards which are extremely exacting and difficult to meet. Other manufacturers avoided the problem by using built-in composite monitors, such as the Commodore PET and TRS-80. The TRS-80 has a slightly modified black and white television as a monitor. It was notorious for causing interference, and production was canceled when

1360-753: The Nintendo Entertainment System reignited the console market, Atari Corporation packaged the 65XE as a game console, with an optional keyboard, as the Atari XEGS . It is compatible with 8-bit computer software and peripherals. The 8-bit computers were sold both in computer stores and department stores such as Sears using an in-store demo to attract customers. Two million Atari 8-bit computers were sold during its major production run between late 1979 and mid-1985. In 1984, Atari reported 4 million owners of its computers and 5200 game console combined. The primary global competition came when

1445-576: The Television Interface Adaptor but universally referred to as the TIA, as part of the Atari 2600 console. The TIA display logically consisted of two primary sets of objects, the "players" and "missiles" that represented moving objects, and the "playfield" which represented the static background image on which the action took place. The chip used data in memory registers to produce digital signals that were converted in realtime via

1530-417: The "excellent 'feel ' " of the keyboard. InfoWorld favorably reviewed the 800's performance, graphics, and ROM cartridges, but disliked the documentation and cautioned that the unusual right Shift key location might make the computer "unsuitable for serious word processing". There is an "Atari key" between the / and shift, whereas a typical keyboard would extend the shift key into this area. Noting that

1615-478: The "players" and "missiles". These consisted of two 8-bit wide objects known as "players", a single 1-bit object known as the "ball", and two 1-bit "missiles". All of these objects could be moved to arbitrary horizontal locations via settings in other registers. The key to the TIA system, and the 2600's low price, was that the system implemented only enough memory to draw a single line of the display, all of which held in registers. To draw an entire screen full of data,

1700-568: The 1200XL in mid-1983, the new models did not arrive until late that year. Although the 600XL/800XL were well positioned in terms of price and features, during the critical Christmas season they were available only in small numbers while the Commodore 64 was widely available. Brian Moriarty stated in ANALOG Computing that Atari "fail[ed] to keep up with Christmas orders for the 600 and 800XLs", reporting that as of late November 1983

1785-507: The 1200XL's than the 400 and 800's, and the "inadequate and frankly disappointing" documentation, ANALOG concluded that "our first impression ... is mixed but mostly optimistic." The magazine warned, however, that because of "Atari's sluggish marketing", unless existing customers persuaded others to buy the XL models, "we'll all end up marching to the beat of a drummer whose initials are IBM." The high-end 1400XL and 1450XLD were announced alongside

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1870-402: The 1450XLD so delayed that it would never ship. Other prototypes which never reached market include the 1600XL, 1650XLD, and 1850XLD. The 1600XL was to have been a dual-processor model capable of running 6502 and 80186 code, and the 1650XLD is a similar machine in the 1450XLD case. These were canceled when James J. Morgan became CEO and wanted Atari to return to its video game roots. The 1850XLD

1955-592: The 1980–81 time frame, when he predicted about one million home computers being sold. The April 1980 issue compared the machines with the Commodore PET , focused mostly on the BASIC dialects. Ted Nelson reviewed the computer in the magazine in June 1980, calling it "an extraordinary graphics box". Describing his and a friend's "shouting and cheering and clapping" during a demo of Star Raiders , Nelson wrote that he

2040-500: The 3 extra color modes, were shipped until October–November 1981. From this point, all new Atari units were equipped with the new chip, now called GTIA, that supported the new color interpretation modes. The original Atari 800/400 operating system supported the GTIA alternate color interpretation modes from the start, which allowed for easy replacement of the CTIA with the GTIA once it was ready. Atari authorized service centers would install

2125-507: The 600XL and 800XL. They added a built-in 300 baud modem and a voice synthesizer , and the 1450XLD has a built-in double-sided floppy disk drive in an enlarged case, with a slot for a second drive. Atari BASIC is built into the ROM and the PBI at the back for external expansion. The 1400XL and the 1450XLD had their delivery dates pushed back, and in the end, the 1400XL was canceled outright, and

2210-437: The 800, "buy an 800 quick!" In May 1981, the Atari 800's price was $ 1,050 (equivalent to $ 3,500 in 2023), but by mid-1983, because of price wars in the industry, it was $ 165 (equivalent to $ 500 in 2023) and the 400 was under $ 150 (equivalent to $ 460 in 2023). The 1200XL was a flop, and the earlier machines were too expensive to produce to be able to compete at the rapidly falling price points. A new lineup

2295-461: The 800. It was discontinued months later, but the industrial design carried over to the 600XL and 800XL released later the same year. After the company was sold and reestablished, Atari Corporation released the 65XE (sold as the 800XE in some European markets) and 130XE in 1985. The XL and XE are lighter in construction, have two joystick ports instead of four, and Atari BASIC is built-in. The 130XE has 128 KB of bank-switched RAM. In 1987, after

2380-529: The 800XL had not appeared in Massachusetts stores while 600XL "quantities are so limited that it's almost impossible to obtain". After losing $ 563 million in the first nine months of the year, Atari that month announced that prices would rise in January, stating that it "has no intention of participating in these suicidal price wars." The 600XL and 800XL's prices in early 1984 were $ 50 higher than for

2465-427: The Atari 5200 console maps it to the $ C0xx hex page. CTIA/GTIA provides 54 Read/Write registers controlling Player/Missile graphics, Playfield colors, joystick triggers, and console keys. Many CTIA/GTIA register addresses have dual purposes performing different functions as a Read vs a Write register. Therefore, no code should read Hardware registers expecting to retrieve the previously written value. This problem

2550-459: The Atari market, and urged readers to contact the companies' leaders. "The Atari 800 computer has been in existence since 1979. Six years is a pretty long time for a computer to last. Unfortunately, its age is starting to show", ANALOG Computing wrote in February 1986. The magazine stated that while its software library was comparable in size to that of other computers, "now—and even more so in

2635-502: The Atari work during a visit to Grass Valley. He realized the Commodore design would not be competitive but he was under a strict non-disclosure agreement with Atari, and was unable to tell anyone at Commodore to give up on their own design. Peddle later commented that "the thing that Jay did, just kicked everybody's butt." Management identified two sweet spots for the new computers: a low-end version known internally as "Candy", and

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2720-622: The Atari ;ST in 1985, Tramiel stated that sales of Atari 8-bit computers were "very, very slow". They were never an important part of Atari's business compared to video games, and it is possible that the 8-bit line was never profitable for the company though almost 1.5 million computers had been sold by early 1986. By that year, the Atari software market was decreasing in size. Antic magazine stated in May 1985 that it had received many letters complaining that software companies were ignoring

2805-469: The CTIA. CTIA processes the sprite and playfield data in the light of its own color, sprite, and graphics registers to produce the final color video output. The resulting system was far in advance of anything then available on the market. Commodore was developing a video driver at the time, but Chuck Peddle , lead designer of the MOS Technology 6502 CPU used in the VCS and the new machines, saw

2890-643: The CTIA/ANTIC pair can display six text modes and eight graphics modes with various resolutions and color depths, allowing the programmer to choose a balance between resolution, colours, and memory use for their display. The original design of the CTIA chip also included three additional color interpretations of the normal graphics modes. This feature provides alternate expressions of ANTIC's high-resolution graphics modes presenting 1 bit per pixel, 2 colors with one-half color clock wide pixels as 4 bits per pixel, up to 16 colors, two-color clock wide pixels. This feature

2975-540: The ECI port. The Atari XEGS (XE Game System) was launched in 1987. A repackaged 65XE with a removable keyboard, it boots to the 1981 port of Missile Command instead of BASIC if the keyboard is disconnected. The Atari machines consist of a 6502 as the main processor, a combination of ANTIC and GTIA chips to provide graphics, and the POKEY chip to handle sound and serial input/output. These support chips are controlled via

3060-547: The FCC rejected the design, delaying that machine's release. TI ultimately shipped early machines with a custom television as the testing process dragged on. To meet the off-the-shelf requirement while including internal TV circuitry, the new machines needed to be heavily shielded. Both were built around very strong cast aluminum shields forming a partial Faraday cage , with the various components screwed down onto this internal framework. This resulted in an extremely sturdy computer, at

3145-509: The Missiles switch from displaying the color of the associated Player object to displaying the value of COLPF3. The new "Player's" position on screen must be set by specifying the position of each Missile individually. Player/Missile pixels are only rendered within the visible portions of the GTIA's pixel engine. Player/Missile objects are not rendered during the horizontal blank or the vertical blank. However, an object can be partially within

3230-540: The OS goes to the "Memo Pad" which is a built-in full-screen editor without file storage support. As the design process for the new machines continued, there were questions about what the Candy should be. There was a running argument about whether the keyboard would be external or built-in. By the summer of 1978, education had become a focus for the new systems. The Colleen design was largely complete by May 1978, but in early 1979

3315-432: The SIO port is not connected, which prevents a few devices from working. The +12V was typically used to power RS-232 devices, which now required an external power source. An improved video circuit provides more chroma for a more colorful image, but the chroma line is not connected to the monitor port, the only place that could make use of it. The operating system has compatibility problems with some older software. The 1200XL

3400-452: The Sweet 8 (or Liz NY) and Sweet 16 projects to create an upgraded set of machines that were easier to build and less costly to produce. Atari ordered a custom 6502, initially labelled 6502C, but eventually known as SALLY to differentiate it from a standard 6502C. A 6502C was simply a version of the 6502 able to run up to 4 MHz. The A models run at 1, and the B's at 2. The basis for SALLY is

3485-458: The VIC-20 and Commodore 64. ANALOG Computing , writing about the 600XL in January 1984, stated that "the Commodore 64 and Tandy CoCo look like toys by comparison." The magazine approved of its not using the 1200XL's keyboard layout, and predicted that the XL's parallel bus "actually makes the 600 more expandable than a 400 or 800." While disapproving of the use of an operating system closer to

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3570-533: The Winter CES in January 1979 and shipped in November 1979. The names originally referred to the amount of memory: 4 KB RAM in the 400 and 8 KB in the 800. By the time they were released, RAM prices had started to fall, so the machines were both released with 8 KB, using 4kx1 DRAMs. The user-installable RAM modules in the 800 initially had plastic casings but this caused overheating issues, so

3655-610: The amount of software and hardware available for the computer "is no match for that of the Apple II or the TRS-80", the magazine concluded that the 800 "is an impressive machine that has not yet reached its full computing potential". Though planning an extensive advertising campaign for 1980, Atari found difficult competition from Commodore, Apple, and Tandy. By mid-1981, it had reportedly lost $ 10 million on sales of $ 10–13 million from more than 50,000 computers. In 1982, Atari started

3740-514: The back of the machine. The original Sweet 8/16 plans were dropped and only one machine using the new design was released. Announced at a New York City press conference on December 13, 1982, the 1200XL was presented at the Winter CES on January 6–9, 1983. It shipped in March 1983 with 64 KB of RAM, built-in self test, a redesigned keyboard (with four function keys and a HELP key), and redesigned cable port layout. The number of joystick ports

3825-411: The beam. Instead of the user's programming updating the CTIA's registers based on its interrupt timing, the new ANTIC would handle this chore, reading data from a framebuffer and feeding that to the CTIA on the fly. As a result of these changes, the new chips provide greatly improved number and selection of graphics modes over the TIA. Instead of a single playfield mode with 20 or 40 bits of resolution,

3910-468: The casings were removed. Later, the expansion cover was held down with screws instead of the easier-to-open plastic latches. The computers eventually shipped with maxed-out RAM: 16k and 48k, respectively, using 16kx1 DRAMs. Both models have four joystick ports, permitting four simultaneous players, but only a few games (such as M.U.L.E. ) use them all. Paddle controllers are wired in pairs, and Super Breakout supports eight players. The Atari 400, with

3995-483: The chipset should be used in a home computer to challenge Apple. To adapt the machine to this role, it needed character graphics, some form of expansion for peripherals , and run the then-universal BASIC programming language. The VCS lacks bitmap graphics and a character generator . All on-screen graphics are created using sprites and a simple background generated by data loaded by the CPU into single-scan-line video registers. Atari engineer Jay Miner architected

4080-464: The computer through a single shielded connector. The internal slots were reserved for ROM and RAM modules; they did not have the control lines necessary for a fully functional expansion card, nor room to route a cable outside the case to communicate with external devices. After Atari announced its intent to enter the home computer market in December 1978, the Atari 400 and Atari 800 were presented at

4165-442: The computers to perform many functions directly in hardware, such as smooth background scrolling, that would need to be done in software in most other computers. Graphics and sound demos were part of Atari's earliest developer information and used as marketing materials with computers running in-store demos. ANTIC is a microprocessor which processes a sequence of instructions known as a display list . An instruction adds one row of

4250-423: The computers were designed with enclosed modules for memory, ROM cartridges, with keyed connectors to prevent them being plugged into the wrong slot. The operating system boots automatically, loading drivers from devices on the serial bus (SIO). The disk operating system for managing floppy storage was menu-driven. When no software is loaded, rather than leaving the user at a blank screen or machine language monitor,

4335-404: The current Playfield display mode. This also means Player/Missile objects can be moved into overscan areas beyond the current Playfield mode. Note that while Missile objects bit patterns share the same byte for displayed pixels ( GRAFM ) each Missile can be independently positioned. When the "fifth Player" option is enabled (See PRIOR/GPRIOR register) turning the four Missiles into one "Player"

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4420-492: The decision was made that Candy would also be a complete computer, but intended for children. As such, it would feature a new keyboard designed to be resistant to liquid spills. Atari intended to port Microsoft BASIC to the machine as an 8  KB ROM cartridge. However, the existing 6502 version from Microsoft was around 7,900 bytes, leaving no room for extensions for graphics and sound. The company contracted with local consulting firm Shepardson Microsystems to complete

4505-489: The disadvantage of added manufacturing expense and complexity. The FCC ruling also made it difficult to have any sizable holes in the case, which would allow RF leakage. This eliminated expansion slots or cards that communicated with the outside world via their own connectors. Instead, Atari designed the Serial Input/Output (SIO) computer bus , a system for daisy-chaining multiple, auto-configuring devices to

4590-591: The future—there is going to be less software being made for the Atari 8-bit computers", warning that 1985 only saw a "trickle" of major new titles and that 1986 "will be even leaner". Computer Gaming World that month stated "games don't come out for the Atari first anymore". In April, the magazine published a survey of ten game publishers which found that they planned to release 19 Atari games in 1986, compared to 43 for Commodore 64, 48 for Apple II, 31 for IBM PC, 20 for Atari ST, and 24 for Amiga. Companies stated that one reason for not publishing for Atari

4675-492: The guy that designed it". Kilobaud Microcomputing wrote in September 1980 that the Atari 800 "looks deceptively like a video game machine, [but had] the strongest and tightest chassis I have seen since Raquel Welch . It weighs about ten pounds ... The large amount of engineering and design in the physical part of the system is evident". The reviewer praised the documentation as "show[ing] the way manuals should be done", and

4760-552: The high-end XL models were canceled and the low-end XLs were redesigned into the XE series. Nearly all research, design, and prototype projects were canceled, including the Amiga-based 1850XLD . Tramiel focused on developing the 68000 -based Atari ST computer line and recruiting former Commodore engineers to work on it. Atari sold about 700,000 computers in 1984 compared to Commodore's two million. As his new company prepared to ship

4845-466: The horizontal blank. The objects' pixels that fall outside of the horizontal blank are then within the visible portion of the display and can still register collisions. The horizontal position range of visible color clocks is $ 22 hex /34 dec to $ DD hex /221 dec . To remove a Player/Missile object from the visible display area horizontal positions (left) 0 and (right) $ DE hex /222 dec (or greater) will insure no pixels are rendered regardless of

4930-936: The left and right edges of the possible Playfield sizes, useful when aligning Player/Missile objects to Playfield components: Three sizes can be chosen: Normal, Double, and Quad width. The left edge (See Horizontal Coordinates ) is fixed and the size adjustment expands the Player or Missile toward the right in all cases. Note that in Quad size a single Player/Missile pixel is the same width as an Antic Mode 2 text character. Player/Missile priority selection mixed with Quad width Player Missile graphics can be used to create multiple text colors per Mode line. Each Player has its own size control register: Size of Player 0 Size of Player 1 Size of Player 2 Size of Player 3 Player size controls: Values: All Missile sizes are controlled by one register, but each Missile can be sized independently of

5015-487: The meeting, Joe Decuir proposed placing an RF modulator on one end, thereby completely isolating any electrical signals so that the computer would have no RF components. This would mean the computer would not have to meet the FCC requirements, yet users could still attach a television simply by plugging it in. His manager, Wade Tuma, later refused the idea saying "The FCC would never let us get away with that stunt." Unknown to Atari, TI used Decuir's idea. As Tuma had predicted,

5100-468: The more stringent FCC requirements came into effect on January 1, 1981. Apple Computer famously left off the modulator and sold them under a third party company as the Sup'R'Mod so they did not have to be tested. In a July 1977 visit with the engineering staff, a Texas Instruments (TI) salesman presented a new possibility in the form of an inexpensive fiber-optic cable with built-in transceivers . During

5185-405: The new machine, a low-end model as a games console, and a high-end version as a home computer. In either role, a more complex playfield would be needed, especially support for character graphics in the computer role. Design of the CTIA was well advanced at this point, so instead of a redesign a clever solution was provided by adding a second chip that would effectively automate the process of racing

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5270-425: The next Vertical Blank. Some Write registers do not have corresponding Shadow registers. They can be safely written by an application without the value being overwritten during the vertical blank. If the application needs to know the last state of the register then it is the responsibility of the application to remember what it wrote. Operating System Shadow registers also exist for some Read registers where reading

5355-470: The others. When the "fifth Player" option is enabled (See PRIOR/GPRIOR register) turning the four Missiles into one "Player" the width is still set by specifying the size for each Missile individually. Values: Each Player object has its own 8-bit pattern register. Missile objects share one register with 2 bits per each Missile. Once a value is set it will continue to be displayed on each scan line. With no other intervention by CPU or ANTIC DMA to update

5440-430: The playfield, much higher resolutions up to 320 pixels horizontally could be supported. Players and missiles were also updated, including four 8-bit players and four 2-bit missiles, but also allowing an additional mode to combine the four missiles into a fifth player. Shortly after design began, the home computer revolution started in earnest in the later half of 1977. In response, Atari decided to release two versions of

5525-634: The port. They recommended writing a new version from scratch, resulting in Atari BASIC . Televisions of the time normally had only one signal input, which was the antenna connection on the back. For devices like a computer, the video is generated and then sent to an RF modulator to convert it to antenna-like output. The introduction of many game consoles during this era had led to situations where poorly designed modulators would generate so much signal as to cause interference with other nearby televisions, even in neighboring houses. In response to complaints,

5610-654: The same time as the Atari 520ST , and they visually resemble the ST. The 65XE has 64 KB of RAM and is functionally equivalent to the 800XL minus the PBI connection. The 130XE has 128 KB of memory, accessible through bank switching . The additional 64K can be used as a RAM drive . The 130XE includes the Enhanced Cartridge Interface (ECI), which is almost compatible with the Parallel Bus Interface, but physically smaller and located next to

5695-490: The similarly equipped Commodore 64 was introduced in 1982. In 1992, Atari Corporation officially dropped all remaining support for the 8-bit line. Design of the "Home Computer System" started at Atari as soon as the Atari Video Computer System was released in late 1977. While designing the VCS in 1976, the engineering team from Atari Grass Valley Research Center (originally Cyan Engineering ) said

5780-471: The size of the Player/Missile object and so no unintentional collisions can be flagged. Horizontal Position of Player 0 Horizontal Position of Player 1 Horizontal Position of Player 2 Horizontal Position of Player 3 Horizontal Position of Missile 0 Horizontal Position of Missile 1 Horizontal Position of Missile 2 Horizontal Position of Missile 3 Below are the color clock coordinates of

5865-495: The specified graphics mode to the display. Each mode varies based on whether it represents text or a bitmap, the resolution and number of colors, and its vertical height in scan lines . An instruction also indicates if it contains an interrupt, if fine scrolling is enabled, and optionally where to fetch the display data from memory. Since each row can be specified individually, the programmer can create displays containing different text or bitmapped graphics modes on one screen, where

5950-467: The standard 400 and 800 compatible cartridge slot. It provides only those signals that do not exist in the latter. ECI peripherals were expected to plug into both the standard Cartridge Interface and the ECI port. Later revisions of the 65XE contain the ECI port. The 65XE was sold as the 800XE in Germany and Czechoslovakia to ride on the popularity of the 800XL in those markets. All 800XE units contain

6035-480: The system would have a three-year lifespan before becoming obsolete. They started blue sky designs for a new console that would be ready to replace it around 1979. They developed essentially a greatly updated version of the VCS, fixing its major limitations but sharing a similar design philosophy. The newer design has better speed, graphics, and sound. Work on the chips for the new system continued throughout 1978 and focused on much-improved video coprocessor known as

6120-600: The two video chips for the Atari 8-bit computers. The CTIA chip includes sprites and background graphics, but to reduce load on the main CPU, loading video registers and buffers is delegated to a dedicated microprocessor, the Alphanumeric Television Interface Controller or ANTIC . CTIA and ANTIC work together to produce a complete display, with ANTIC fetching scan line data from a framebuffer and sprite memory in RAM, plus character set bitmaps for character modes, and feeding these to

6205-425: The user code would wait until the television display reached the right side of the screen and update the registers for the playfield and player/missiles to correctly reflect the next line on the display. This scheme drew the screen line-by-line from program code on the ROM cartridge , a technique known as "racing the beam". Atari initially estimated that the 2600 would have short market lifetime of three years when it

6290-471: The value directly from hardware at an unknown stage in the display cycle may return inconsistent results. In the individual register listings below the following legend applies: These registers specify the horizontal position in color clocks of the left edge (the high bit of the GRAF* byte patterns) of Player/Missile objects. Coordinates are always based on the display hardware's color clock engine, NOT simply

6375-446: The values the result is vertical stripe patterns the height of the screen including overscan areas. This mode of operation does not incur a CPU or DMA toll on the computer. It is useful for displaying alternate colored borders and vertical lines separating screen regions. Graphics pattern for Player 0 Graphics pattern for Player 1 Graphics pattern for Player 2 Atari 400 The Atari 8-bit computers , formally launched as

6460-506: Was announced at the 1983 Summer CES , closely following the original Sweet concepts. The 600XL is essentially the Liz NY model and the spiritual successor of the 400, and the 800XL would replace both the 800 and 1200XL. The machines follow the styling of the 1200XL but are smaller from back to front, and the 600XL is more so. Atari had difficulty in transitioning manufacturing to Asia after closing its US factory. Originally intended to replace

6545-401: Was designed in 1976, which meant the company would need a new design by 1979. Initially this new design was simply an updated 2600-like game console, and was built around a similar basic design, simply updated. Work on what would become the CTIA started in 1977, and aimed at delivering a system with twice the resolution and twice the number of colours. Moreover, by varying the number of colours in

6630-436: Was discontinued in June 1983. Compute! stated in an early 1983 editorial that the 1200XL was too expensive; John J. Anderson of Creative Computing agreed. Bill Wilkinson, author of Atari BASIC, co-founder of Optimized Systems Software , and columnist for Compute! , criticized the computer's features and price. He wrote that the 1200XL was a "terrific bargain" if sold for less than $ 450, but that if it cost more than

6715-419: Was initially designed as a game console, lacking a keyboard and input/output ports, although an external keyboard was planned for joystick ports 3 and 4. At the time, plans called for both to have a separate audio port supporting cassette tapes as a storage medium. A goal for the new systems was user-friendliness. One executive stated, "Does the end user care about the architecture of the machine? The answer

6800-448: Was ready before the computers' November 1979 debut, but was delayed so much in the development cycle that Atari had already ordered a batch of about 100,000 CTIA chips with the graphics modes missing. Not wanting to throw away the already-produced chips, the company decided to use them in the initial release of the Atari 400 and 800 models in the US market. The CTIA-equipped computers, lacking

6885-407: Was reduced from 4 to 2. There is no PAL version of the 1200XL. Announced at a retail price of $ 1000, the 1200XL was released at $ 899 (equivalent to about $ 2,800 in 2023). This is $ 100 less than the announced price of the Atari 800 at its release in 1979, but by this time the 800 was priced much lower. The system uses the SIO port again instead of the Parallel Bus Interface. The +12V pin in

6970-444: Was so impressed that "I've been in computer graphics for twenty years, and I lay awake night after night trying to understand how the Atari machine did what it did". He described the machine as "something else" but criticized the company for a lack of developer documentation. He concluded by stating "The Atari is like the human body – a terrific machine, but (a) they won't give you access to the documentation, and (b) I'd sure like to meet

7055-518: Was the unusually high amount of software piracy on the computer, partly caused by the Happy Drive . The magazine warned later that year, "Is this the end for Atari 800 games? It certainly looks like it might be from where I write". In 1987, MicroProse confirmed that it would not release Gunship for the Atari 8-bits, stating that the market was too small. The 65XE and 130XE (XE stands for XL-Compatible Eight-bit) were announced in 1985 at

7140-648: Was to have been based on the Lorraine chipset which became the Amiga . Commodore founder Jack Tramiel resigned in January 1984 and in July, he purchased the Atari consumer division from Warner for an extremely low price. No cash was required, and instead Warner had the right to purchase $ 240 million in long-term notes and warrants, and Tramiel had an option to buy up to $ 100 million in Warner stock. When Tramiel took over,

7225-414: Was very expensive, the TIA could not afford this solution. Instead, the system implemented a display system that used a single 20-bit memory register that could be copied or mirrored on the right half of the screen to make what was effectively a 40-bit display. Each location could be displayed in one of four colors, from a palette of 128 possible colors. The TIA also included several other display objects,

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