Atari 800XL

The Atari 800XL is a home computer produced by the American company Atari, Inc. It is based on a custom variant of the 6502 microprocessor.

Atari 800XL

Atari 800XL
Developer	Mark Lutvak (lead), Joe Decuir (ANTIC), George McLeod (GTIA), Doug Neubauer (POKEY), Steve Mayer Research Lab (hardware, operating system),[1] Regan Cheng (case)[2]
Manufacturer	Atari, Inc. (until July 1984) Atari Corporation (from July 1984)
Release date	USA November 1983; UK November 1983; Germany April 1984
Introductory price	USA US$299 UK £249 Germany ~800 DM
Discontinued	November 1985 Germany early 1990s
CPU	MOS 6502 "Sally" @ 1.79 MHz (NTSC), 1.77 MHz (PAL)
Memory	64 KB DRAM
Graphics	Various text and graphics modes 8 monochrome sprites ("Players" and "Missiles") Color selection from a 256-color palette
Sound	4 sound generators (output via TV)

The computer is an evolution of the Atari 1200XL, released in the United States in March 1983. The core electronics and visual design were largely retained, with technical improvements focused on expandability and simplified production. Positioned as a direct competitor to the Commodore 64, Atari equipped the 800XL with 64 kilobytes (KB) of RAM. Like the entry-level Atari 600XL, which had only 16 KB of RAM, the Atari BASIC programming language is built into the computer and available upon startup.

The device launched globally at the end of 1983, accompanied by extensive advertising campaigns. During the 1983 Christmas season, delayed production limited availability, causing Atari to lose significant market share to competitors, particularly the Commodore 64. Following Atari's acquisition by Jack Tramiel, drastic price reductions were implemented worldwide by the 1984 Christmas season. These made the Atari 800XL the most affordable computer in its performance class but failed to displace the Commodore 64 as the market leader.

After the introduction of the successor XE series in early 1985, production of the Atari 800XL continued in parallel until November 1985. As demand waned in North America and Western Europe from mid-1986, the computer saw an unexpected resurgence in Comecon countries, achieving market leadership alongside the XE series. This strong demand prompted a production restart in July 1988. By late 1992, Atari discontinued support and production of its 8-bit computers.

Upon release, the trade press praised the computer's attractive design, solid build quality, built-in Atari BASIC, and extensive range of peripherals and software.

History

• 
  Atari 400
• 
  Atari 800
• 
  Atari 1200XL
• 
  Atari 600XL

After the Atari 400 and Atari 800, produced since 1979, became outdated and the Atari 1200XL proved unsuccessful, Atari aimed to introduce modern, cost-effective devices in 1983 to recover from financial difficulties. The company hoped to compete with Commodore International and the Commodore 64 in the high-end home computer segment.^[3]

Development

Atari envisioned a computer compatible with its predecessors, adopting the Atari 1200XL's design but addressing its shortcomings and adding expansion options. Given the market conditions, two configurations were planned. The entry-level model with 16 KB of RAM—the later Atari 600XL—was intended to compete with the Commodore VC 20 and Sinclair ZX Spectrum, while the higher-end 64 KB model targeted the Commodore 64's market share. Internally codenamed "Surely" and "Surely Plus,"^[4] these projects leveraged resources and staff from the "Liz" project, which had produced the Atari 1200XL.^[5]

Project "Surely Plus"

Development of the higher-end XL variant began in March 1983, based on the system architecture of previous models, using custom chips ANTIC, GTIA, and POKEY, and a specialized MOS 6502 variant named "SALLY," previously used in the Atari 1200XL. Innovations included integrating the Atari BASIC programming language and adding an expansion port.^[6]

Renaming to Atari 800XL, Introduction, and Delayed Production

• 
  Introduction at Summer CES 1983

The newly named Atari 800XL was unveiled alongside new peripherals at the Consumer Electronics Show (CES) in Chicago in early June 1983.^[7] Atari invited representatives from major national user groups to evaluate the devices, aiming to identify potential flaws before production to avoid the Atari 1200XL's failure.^[8]

The computer soon passed electromagnetic compatibility tests by the U.S. Federal Communications Commission (FCC), a prerequisite for U.S. sales. Development for compatibility with various television standards, such as PAL, was completed, and PAL units were showcased at the Internationale Funkausstellung Berlin in late summer 1983. Production transfer to Hong Kong was delayed by a month due to a leadership change at Atari,^[9] as was the manufacturing of European-market units in Ireland.^[10]

Marketing

• 
  Alan Alda (2008)

Atari marketed the 800XL as a powerful, user-friendly device for beginners ("We made them smart enough to know you’re only human," "Discover what you and Atari can do") and small users, for education, and gaming ("You’ll do more with Atari home computers," "The 800XL: power enough for over 2,000 programs").^[11] The campaign featured large newspaper ads and TV commercials, with U.S. actor Alan Alda, introduced at the June 1983 CES, as the spokesperson. His five-year, $5 million engagement followed extensive market research by Atari.^[12][13]

Market Launch and Supply Issues

The Atari 800XL launched in North America and Great Britain in late November 1983, priced at $299 in the United States^[14][15] and £249 in the UK.^[16] Initial production delays meant only 60% of pre-ordered units were delivered by Christmas in North America,^[15] even with costly air freight imports.^[17] The entire 1983 production of approximately 400,000 Atari 600XL and 800XL units sold out by year-end.^[18][19] Due to supply shortages, significant quantities reached France and West Germany only in April 1984,^[20] priced at 3200 francs^[21] and ~800 DM, respectively.^[22] A SECAM variant for France was available from June 1984 for 3500 francs.^[23] In Italy, the computer likely launched around the same time for 707,000 lire.^[24]

Price Increase and Olympic Sponsorship

In early 1984, Atari raised wholesale prices for the XL series by $40 in North America, citing a desire to sell at cost and end the destructive price war in the home computer industry.^[17] Marketing efforts increasingly targeted educational institutions like schools.^[25] In summer 1984, Atari sponsored the Olympic Games in Los Angeles, branding the 800XL as the "Official Home Computer of the 1984 Olympics" to enhance its prestige. The company also secured extensive TV advertising contracts to reach more potential buyers.^[26][27]

After Jack Tramiel's Acquisition of Atari and Initial Price Cuts

• 
  Jack Tramiel (2007)

Following Jack Tramiel's unexpected acquisition of Atari in July 1984,^[28] uncertainty surrounded the XL series' future. Tramiel's plans, however, only discontinued the unprofitable Atari 600XL.^[29] With ~100,000 800XL units in stock^[30] and production optimizations from August 1984 yielding ~150,000 units monthly,^[31][32] significant price reductions followed.^{[note 1]}

"Power without the Price" and "Marketing for the Masses"

From November 1984, under Tramiel's slogan "Power without the Price," further price cuts swept Europe.^{[33][note 2]} A pre-Christmas price drop to $120 in the U.S. and £130 in the UK, matching the Sinclair ZX Spectrum,^{[34][note 3]} sparked speculation of a sell-off for new models.^[35] Rumors were fueled by Atari's September hints at a refreshed 800XL successor.^[36] Atari denied these, attributing the aggressive pricing to further production optimizations^[34] and confirming continued production.^[37] The price war, with prices in West Germany dropping from ~650 to 500 DM in December 1984, targeted the Commodore 64's market share.^[38]

Under Tramiel's "Marketing for the Masses" strategy, bundle deals proliferated in Europe. For example, the UK chain Laskys offered the Starter Pak—including the computer, Atari 1010 cassette recorder, joystick, manuals, and software—for £170 from December. This made the 800XL one of the cheapest in its class, outpricing the Commodore 64 and MSX computers.^{[34][note 4]} In 1984, Atari sold ~600,000 800XL units globally^[39] and ranked among the top three school computers in the U.S.^[40] However, it failed to overtake the Commodore 64, which sold roughly four times as many units.^[41]

Further price cuts cfter XE Series introduction, bundle deals

In January 1985, Atari introduced the Atari ST series and updated 8-bit computers, including the Atari 130XE with 128 KB RAM, at the CES in Las Vegas. The memory management unit "FREDDY," originally planned for the 800XL, was incorporated into the new models.^[42] With the 130XE's U.S. launch in February 1985, the 800XL's price—its production cost now reduced to $80^[43]—dropped further, reaching just under £100 in the UK.^[44] Atari promoted floppy disk drives to beginners with bundles like the Personal Computer Pack, including the computer, Atari 1050 drive, and software, for ~£250.^[45]

From August 1985, Atari offered UK educational institutions up to 25% discounts and launched the Atari LOGO System bundle with the beginner-friendly Logo to challenge Acorn's BBC Micro in schools.^[46] In September 1985, the Netherlands selected the 800XL as the official school computer, anticipating ~100,000 sales from educational and private purchases.^[47]

Sell-Off in the west

Dixons store in Sheffield

After announcing the 800XL's production halt in November 1985, UK retailer Dixons took over remaining stock. Christmas bundles, including the 800XL, Atari 1050 drive, software, and joystick, sold for ~£170, setting new lows in the home computer market.^[48] ~100,000 units likely sold in the UK by Christmas.^[49] In the U.S., the 800XL sold for under $100 during the holidays.^[50] In West Germany, prices of 200–250 DM boosted sales,^[51][52] but the 800XL's 1985 market share was ~6%, far behind the Commodore 64's ~40%, with the Amstrad CPC 464 at ~15% and Sinclair ZX Spectrum at ~9%.^[53]

By February 1986, most 800XL stock was sold in the UK.^[54] In West Germany, stock lasted until Q2 1987,^[55] with ~92,000 units sold in 1986.^[56] The Atari 65XE, sold in Canada earlier, replaced the 800XL in North America and the UK from 1986, while the identical Atari 800XE launched in Germany in October for just under 200 DM.^[57] By mid-1986, Atari's 8-bit user base reached ~300,000 in the UK^[58] and over 1 million in North America.^[59]

Market leadership in the Eastern Bloc

• 

With relaxed export restrictions on high-tech goods in late 1984,^[60] the 800XL was exported to Eastern Bloc countries from 1985. Available through state trade organizations for hard currency, in the GDR, sales occurred via Forum Außenhandelsgesellschaft's Intershop network using Forum checks equivalent to the Deutsche Mark. In Poland, Pewex stores sold 5,500 units in 1985, which sold out quickly.^[61] At the black market rate, an 800XL with an Atari 1010 cassette recorder cost ~150,000 zloty—a university professor's annual salary—later dropping to 120,000–130,000 zloty after trade liberalization.^[62] The low price displaced the Sinclair ZX Spectrum, making Atari the market leader in Poland.^[63] In Czechoslovakia, Tuzex stores offered Atari computers for equivalent currency.^[64][65]

In 1987, ~100,000 Atari 8-bit computers shipped to the Eastern Bloc, including 4,600 to the GDR—where the 800XL was the first officially imported Western home computer from 1985^[66]—and 10,500 to Czechoslovakia.^[67] By 1987, Atari’s XL and XE series led markets in both countries.^[68] At the 1990 Leipzig Spring Fair, Atari estimated ~100,000 computers sold in the GDR via Forum.^[69] Additional units reached users through private imports or Genex gifts from Western relatives.^[70]

Comeback in the West

In West Germany, sales surged, with Atari reporting ~500,000 units sold by July 1988. To meet demand not fully covered by the XE series, Atari resumed 800XL production in July 1988, offering it with the Atari XC12 cassette recorder for just under 200 DM.^[71]

Modern Reproductions

The Atari 800XL’s straightforward architecture and extensive documentation enable miniaturized reproductions using modern technology. In 2014, a reproduction was implemented on a FPGA with an embedded system, initially as a feasibility study. It proved practical, offering a compact, reliable, and portable alternative to the original hardware.^[72]

Technical Specifications

The Atari 800XL’s electronics are housed on a single board, including peripheral connectors and an external system bus for expansions.

Mainboard of the computer. Hover over components with the mouse to identify them and click for more information.

Main processor

The Atari 800XL uses a variant of the 8-bit MOS Technology 6502 microprocessor, common in contemporary computers. Unlike the Atari 400 and 800, it employs a custom "Sally" variant, reducing the number of electronic components. The CPU accesses a 65,536-byte address space, limiting RAM to 64 kilobytes (KB). The system clock is 1.77 MHz for PAL and 1.79 MHz for NTSC systems.

Custom chips for graphics and sound

The computer architecture relies on three Atari-developed custom chips: Alphanumeric Television Interface Controller (ANTIC), Graphic Television Interface Adaptor (GTIA), and Potentiometer and Keyboard Integrated Circuit (POKEY), designed for flexibility and to offload the CPU.

Mix of two graphics modes (large and normal text) using a raster interrupt

ANTIC and GTIA generate the display for TVs or monitors, using data from a "Display List" in RAM set by the OS or user. GTIA supports up to eight monochrome sprites ("Players" and "Missiles"), integrated into ANTIC’s background per user-defined overlap rules and checked for collisions with each other or the "Playfield." These features, evident in their naming, simplify game development with interactive graphics.^[73] Together, ANTIC and GTIA offer unmatched display flexibility among contemporary home computers.^[74] POKEY handles four-channel sound generation, keyboard input, and the Serial Input/Output (SIO) interface for peripheral communication.^[75]

These LSI chips consolidate many components, reducing cost and space. Their unpublished designs prevented economical copying, deterring illegal cloning common in the industry.^[76]

Overview of graphics modes provided by the Atari 800XL operating system^[77]

Graphics Mode	Display Type	Resolution (Pixels)	Colors	Memory Usage (Bytes)
0	Normal text	40 × 24	2	992
1	Large text	20 × 24	5	672
2		20 × 12	5	420
3	Pixel graphics	40 × 24	4	432
4		80 × 48	2	696
5			4	1176
6		160 × 96	2	2184
7			4	8138
8		320 × 192	2
9	GTIA modes	80 × 192	16
10			9
11			16
12	Text (character set)	40 × 24	5	1152
13		40 × 12	5	660
14	Pixel graphics	160 × 192	2	4296
15			4	8138

Memory and memory allocation

The address space, accessible by the CPU and ANTIC, is divided into segments. Addresses are typically denoted in hexadecimal with a "$" prefix, ranging from $0000 to $FFFF (0 to 65,535 in decimal).

The $0000–$BFFF range is primarily for RAM, though not fully user-accessible, as $0000–$06FF is reserved for OS variables. Self-test routines copy from ROM to $5000–$57FF when activated. An 8 KB ROM cartridge maps to $A000–$BFFF, replacing BASIC; a 16 KB cartridge spans $8000–$BFFF. The OS resides from $C000, with hardware registers (ANTIC, GTIA, POKEY, etc.) in the $D000–$D7FF "Input/Output Block." From $D800–$FFFF, the remaining OS and parallel peripheral drivers reside. Disabling the OS and BASIC allows up to 62 KB of RAM to be used.^[78]

On startup, the CPU reads the OS ROM, checks the cartridge slot, and runs any program found. If none, it queries the Option and Start keys. Pressing Option disables BASIC, loading a program from a disk drive; Start loads from a cassette. Without key input, BASIC starts with a blinking cursor.^[79]

Input and output interfaces

External connections include two controller ports on the right, a ROM cartridge slot on top, a coaxial RF antenna output for TVs, and a proprietary serial interface (Serial Input/Output, SIO) port on the back for "intelligent" peripherals using a custom Atari protocol and connector. Printers, disk drives, and other devices with daisy chain SIO ports connect via a single cable type. Unlike the Atari 1200XL, the 800XL features a Parallel Bus Interface (PBI) on the rear, enabling external expansion like the unreleased Atari 1090 box.^[80]

Hover over components/ports with the mouse to identify them and click for more information if available.

Peripherals

The Atari 800XL is compatible with all peripherals released by Atari for its 8-bit computers. This section primarily focuses on the commercial products released by Atari in the XL design up to 1989.

Mass Storage

Main articles: Mass Storage for Atari 400, 800; XL; and XE

• 
  Compact Cassette
• 
  5¼″ Floppy Disk

In the context of 1980s home computers, particularly in Western markets, data storage primarily utilized cassette recorders and floppy disk drives, with hard drives and removable disk drives increasingly used in professional environments. The cheapest method, using compact cassettes, generally suffered from low data transfer rates and long loading times, while the faster and more reliable floppy and hard disk drives were significantly more expensive.^[81] Upon its release, the Atari 800XL supported program recorders, as well as floppy disk systems like the Atari 1050 and, later, hard disk systems for mass storage. Hard disk systems from Corvus, compatible with the Atari 800, were not usable with the 800XL due to the absence of certain connectors.

Cassette Systems

Unlike other contemporary home computers, such as the Tandy TRS-80 or the Sinclair ZX81, the Atari 800XL cannot use standard cassette recorders for data storage out of the box. Instead, it requires a device tailored to its serial interface—the Atari 1010 program recorder. The average data transfer rate is 600 bits/s, with a 30-minute cassette capable of storing 50 KB of data.^[82] The device features a stereo head, allowing music or spoken instructions to be played alongside data reading.^[83] To save cost and space, the program recorder lacks a built-in speaker, with audio signals output via the television using the POKEY chip.

In late 1986, a commercial hardware solution called Rambit was introduced in the UK for approximately 20 British pounds. This involved soldering a pre-assembled board and using a supplied converter program, enabling the modified Atari 1010 to load data at rates of 3300 to 3600 bits/s.^[84]

Floppy Disk Systems

Atari 1050

With the introduction of the Atari 800XL, a matching floppy disk drive, the Atari 1050, was available. This drive can write to 5¼″ floppy disks on one side, storing up to 127 KB of data. The original disk operating system, DOS 2.0s, supported only single density, allowing 88 KB per disk side with 128-byte sectors. By mid-1984, it was replaced by DOS 3.0, which supported Atari’s proprietary Enhanced Density mode. Unlike double density, this mode increases the number of sectors per track rather than bytes per sector, resulting in a proprietary capacity of 127 KB .^[85] Due to DOS 3.0’s incompatibility with DOS 2.0s, Atari released the improved DOS 2.5 in 1985.^[86] The Atari 1050 cost approximately $450 in mid-1984.^[87]

Alongside the Atari 800XL’s release, various third-party Atari-compatible floppy drives were available, most supporting 5¼″ disks with double density. These included devices from Percom,^[88] the Rana 1000 for $400^[89] and the dual-drive Astra 1620 for $600.^[90] In 1984, additional high-performance drives emerged: the Percom AT-88 for $420,^[91] the Trak AT-D2 for $500, the double-sided Trak AT-D4,^[92] and the Indus GT for $500.^[93] Unique were the Amek AMDC I for $550 and the dual-drive Amek AMDC II for $760,^[94] both using the rare 3″ disks. Many third-party drives included connection materials, documentation, and operating systems like SmartDOS or DOS XL.^[95]

In 1985, floppy drive costs decreased, sales increased, and enhancements for the Atari 1050 were introduced, reducing access times and increasing capacity to 180 KB per side with double density. Notable “floppy speeders” included US-Doubler,^[96] Happy Enhancement 1050,^[97] Super Archiver I & II with or without BitWriter,^[98] and German products like High Speed 1050 from Irata-Verlag,^[99] 1050 Turbo from Gerhard Engl,^[100] and various Speedy 1050 versions from Compy Shop.^[101] These modifications included software like SpartaDOS, WarpDOS, or BiboDOS.^[97] By the 1990s, due to limited Atari drive availability, small-scale custom builds emerged, such as Floppy 2000 I and II from Klaus Peters Elektronik^[102] and Polish products like California Access CA-2001 and TOMS 720.^[103]

Hard Disk systems

From early 1986, third-party manufacturers introduced hard disk systems and software for the Atari 800XL. Supra Corporation’s Supra Drive was among the earliest, connecting via the external parallel bus. With included software like MyDOS, its 10 MB storage was versatile. However, its fast access times and high transfer rates came at a high cost: approximately $800 in early 1986, about four times the price of the Atari 1050.^{[104][105][106]} The BTL Hard Disk System, introduced in late 1986, also offered 10 MB, expandable to 128 MB, and shipped with MyDOS for about $600.^[107] In 1987, ICD Inc. introduced the FA-ST with 20 MB and SpartaDOS for around $700.^[108] By 1989, Computer Software Services offered systems with 5 to 80 MB based on The Black Box!, priced from $400 (10 MB) to nearly $900 (80 MB).^[109]

Due to issues with transferring copy-protected programs to hard disks and their high cost, these systems were primarily used by operators of storage-intensive mailboxes and professional developers.^[110]

Output Devices

Display Devices

The Atari 800XL’s video output can be displayed via a built-in RF modulator on a standard television. Higher image quality is achievable with dedicated monitors. By May 1985, over 15 monochrome monitors were available in West Germany, each costing less than 500 DM. Eight color monitors, priced under 1500 DM, were also available.^[111] Atari did not produce a monitor specifically for the XL series.

Printers

Main articles: Printers for Atari 400, 800; XL; and XE

• 
  Atari 1027
• 
  Atari 1020

Various printers from Atari and third parties were used for text and graphics output. With the Atari 800XL’s release, Atari offered the four-color plotter Atari 1020 for $299,^[112] the needle-based Atari 1025, and the letter-quality Atari 1027. Connecting more advanced third-party printers required a Printer Interface connected to the SIO port, providing standard interfaces like RS-232 or Centronics. By 1984, these enabled the use of daisywheel printers like the Transstar 120, inkjet printers like the Hewlett-Packard Thinkjet, and dot-matrix printers like the Gemini 10X.^[113] Expensive color thermal printers like the 1985 Okimate 10 and the needle-based Seikosha GP-700A were also supported.^[114] These printers required specific device driver software.

In September 1985, Atari introduced the more capable needle-based Atari 1029, which supported graphics output.^[115] By early 1986, third-party printers like the Gemini 10X, Star SG-10, and various Epson models had largely replaced Atari’s aging models, according to an Antic Magazine survey.^[116] Printer compatibility depended on available interfaces and drivers, with Epson compatibility often required.^[117]

Other Output Devices

Third-party output devices included speech synthesis devices like The Voicebox and The Voicebox II from The Alien Group^[118][119] and the 1986 Voice Master from Covox.^[120] Other devices included a DIY 3D glasses for stereographic content on a TV^[121] and a programmable robotic arm.^[122]

Input Devices

Main article: Atari Input Devices

Atari 800XL with closed cartridge slot cover

Atari 800XL with closed cartridge slot cover. Hover over components with the mouse to identify them and click for more information.

Keyboard, Mouse, Trackball, and Joysticks

The Atari 800XL’s typewriter-style keyboard includes 56 keys, a spacebar, and four function keys. The computer can alternatively be operated with a mouse, requiring compatible software like desktop publishing or drawing programs.^[123][124] Trackballs, paddle controllers, and joysticks from various manufacturers were also available, with joysticks primarily used for gaming.

Graphics Tablets

Graphics tablets quickly became popular for drawing programs, using a touch-sensitive surface to detect a stylus’s position, enabling faster and more efficient image creation compared to joystick-based programs. By late 1984, available tablets for Atari XL computers included Atari’s Touch Tablet for about $90, Koala Technologies’ Koala Touch Tablet for around $125, and Chalk Board’s Power-Pad. These required compatible software like Micro Illustrator. After the discontinuation of Touch Tablet and Koala Touch Tablet, Suncom’s Animation Station became available in 1987 for about $90.^[125]

Light Pens

An alternative to joysticks or graphics tablets, light pens allowed direct drawing or program operation on the screen. Their functionality relies on detecting the electron beam of a cathode ray tube display, limiting use to CRT-based devices. By fall 1984, light pens from four manufacturers were available: Atari’s Light Pen for about $100, Futurehouse’s Edumate Light Pen for $35, Tech Sketch’s Tech Sketch Light Pen starting at $40, and Madison Computer’s Mc Pen for $49. Each included software, with Atari’s cartridge-based Atari Graphics considered the most powerful.^[126]

Data Communication

Beyond removable media like cassettes and disks, various methods existed for data exchange between computers, including different types, via wired or wireless transmission. For long distances where direct cabling (e.g., the popular SIO-2-PC solution^[127]) was impractical, data could be transmitted via telephone or radio networks. However, 1980s network infrastructure required converting digital data into analog signals for transmission and back to digital upon receipt, a task handled by modems. Many modems, especially third-party ones, required an additional interface unit, often called a Modem-Interface.^[128]

In West Germany, legal considerations, such as approval by the Deutsche Bundespost, were significant. For instance, operation of North American modems like the Atari 830, Atari 835, and Atari 1030 was prohibited due to lack of postal certification.^[129]

Acoustic Couplers

Until the mid-1980s, acoustic couplers were among the cheapest modems, usable with public payphones. However, they were slow and unreliable due to acoustic signal transmission via the telephone handset, which was susceptible to external noise. North American Atari 800XL users had access to the Atari 830 modem with a 300-baud transfer rate. Numerous third-party couplers were also available. In West Germany, the post-approved Ascom-Modem from Dynamics Marketing GmbH was available by mid-1985.^[130]

Direct Modems

Direct modems connected data electrically to the phone line, avoiding the error-prone handset method. Atari’s Atari 1030 for the XL series offered a 300 bit/s transfer rate with low memory requirements, making it compatible with the 16 KB Atari 600XL without a floppy drive. Priced at about $60 in late 1985, it was among the cheapest for Atari computers. Third-party modems like Hayes Smartmodem, Signalman Express, and Atari’s SX-212 supported up to 2400 bit/s but were more expensive. Their practical use in West Germany was limited until the late 1980s due to scarce mailboxes supporting even 1200 bit/s.^[131]

Radio Modems

Popular in amateur radio, radio modems transmitted data via radio waves without a specific target, allowing multiple recipients with compatible equipment to receive it. This was ideal for broadcasting data to many users. Their limited range could be extended to create networks. With a transfer rate of 300 baud, they were cost-effective, avoiding high long-distance call fees of the 1980s.^[132] By late 1985, commercial radio modems for the Atari 800XL included Kantronics’ Kantronics Interface II and Macrotronics’ RM 1000.^[133]

Upgrades

Various upgrades enhanced the Atari 800XL’s performance, divided into internal modifications (often requiring soldering) and external solutions using the computer’s interfaces (expansion port, cartridge slot, joystick ports, SIO). External upgrades preserved warranty claims by avoiding case opening.^[134] The following covers commercial solutions reviewed by contemporary trade press.

Memory

Some memory upgrades required opening the computer, while others used the expansion port. These enabled virtual floppy drives or printer buffers.^[135] Some included battery backups or independent power to retain data when powered off. The Atari 1064 memory module for the Atari 600XL was incompatible with the 800XL due to design differences.

Notable upgrades included ICD’s Rambo XL with 256 KB,^[136] Newell 256 KB,^[137] Magna Systems’ Ramcharger with up to 1 MB,^[138] and a 256 KB module from Compy Shop in West Germany.^[139] ICD’s Multi I/O Board, available from late 1986, supported 256 KB or 1 MB.^[140]

Interface Units

Data exchange between the Atari 800XL and devices like the Atari 1050 used protocols incompatible with standards like RS-232 or Centronics. Converters, or Interface Boxes, often combined hardware and software, some with memory for buffering print data.^[141]

By late 1984, Centronics printer converters included Microbits’ MPP-1150 Printer Interface and Digital Devices’ Ape-Face for about $100.^[142] More expensive units offered up to 512 KB for buffering large print jobs.^[143] In West Germany, the 850XL Interface Box with RS-232 and Centronics was available from 1985.^[144] Later, advanced units like ICD’s Multi I/O Board and P:R: Connection Box^[145] and Computer Software Services’ The Black Box!^[146] were introduced.

80-Column Display (Hardware)

80-column upgrades improved screen readability but required monitors due to their 560-pixel horizontal resolution, unsuitable for TVs.^[147] Notable solutions included TNT-Computing’s ACE80XL^[148] and ICD’s Multi I/O Board with an 80-column card.^[149]

System modifications

Some extensions directly target the system architecture, specifically the function of the main processor. These either manipulate the processor or replace it with a different microprocessor. The first group includes devices known as Freezers. When activated by the user during operation, a Freezer halts the program execution by stopping the main processor, taking control of all system functions. Freezers are designed to allow users to manipulate the system state after "freezing," ranging from modifying specific memory areas to saving the entire system state to a floppy disk or loading it from a disk. Such functionalities are useful for debugging programs, bypassing copy protection mechanisms, or saving game states that cannot otherwise be preserved.^[150][151] The second group of system extensions involves replacing the main processor with a more powerful variant or a different processor type to, for example, enable the use of software from other systems.^[152]

The only commercially available hardware-based Freezer for the Atari 800XL was the Turbo Freezer XL by Bernhard Engl. It was available from 1987 for approximately 150 DM, exclusively in West Germany. It connects to the external system bus, the computer’s expansion port.^[153] With the ATR-8000 interface unit from SWP Microcomputer Products, also connected to the expansion port, it is possible to run a variety of programs for CP/M systems and IBM-compatible computers using the Atari 800XL as a terminal, thanks to the built-in microprocessors.^{[note 5][154]} The Turbo-816, advertised from late 1988, includes a backward-compatible 16-bit microprocessor 65816 along with appropriate control electronics and a tailored operating system. To fully utilize the advantages of the alternative processor, such as its larger directly accessible memory, existing programs must be modified.^[155]

EPROM Programmers

To make programs like system software immediately available upon startup, they were stored in ROM or modifiable EPROMs. EPROMs required a UV lamp for erasing and an EPROM programmer for writing.^[156] Thompson Electronic’s ProBurner, connected via the cartridge slot, supported EPROMs from 2 to 16 KB and was considered top-tier by December 1985.^[157] In West Germany, Compy Shop’s BiboBurner from 1986 supported up to 32 KB.^[158] From 1990, Computer Software Services offered the Super E-Burner and later The Gang Super E-Burner.^[159]

Digitizers for Graphics and Music, MIDI

Converters like digitizers and scanners transferred printed or video images into the computer. Digital Vision’s Computer Eyes Digitizer, available from 1985 for $130, digitized video camera images, including filmed documents, with included software.^[160] In West Germany, Irata-Verlag’s Digitizer offered similar functionality.^[161] Innovative Concepts’ Easy Scan scanned paper documents but required mounting its optics on a printer’s printhead.^[162]

Sound digitizers, like Sound Samplers and MIDI Interfaces, converted analog audio or speech. Notable devices came from 2-Bit-Systems,^[163][164] Alpha Systems,^[165] Hybrid Arts,^[166] and Wizztronics.^[167] In West Germany, Ralf David’s Sound ’n’ Sampler was available from 1987 with software.^[168]

Software

The software range for the Atari 800XL computer included commercial programs distributed by Atari and the Atari Program Exchange (APX), as well as software developed by third-party manufacturers and published in magazines and books as listings for users to type in.

As with other home computers of the 1980s, commercial software was distributed on various media. Compact cassettes, popular among game developers due to their low cost, were prone to errors due to the mechanical stress on the magnetic tape and were often associated with long loading times. Additionally, certain operating modes, such as the relative addressing advantageous for database operations, were not possible with cassettes. In contrast, the more expensive plug-in modules provided instant access to programs upon powering on the computer, which was particularly beneficial for system software and frequently used applications. Floppy disks offered the best compromise between loading time, supported operating modes, reliability, and storage capacity.^[169] Their use was supported by Atari’s floppy disk drives and those from other manufacturers upon the release of the Atari 800XL. Due to the high cost of floppy disk drives in 1983 and 1984, plug-in modules and compact cassettes were the most commonly used storage media for Atari computers until then.^[170] This situation changed when Atari significantly reduced the price of the 1050 floppy disk drive starting in 1985.

Illegal copies consistently accounted for a significant portion of the software in circulation, particularly in Eastern Bloc countries, where original Western software was virtually nonexistent until the fall of the Iron Curtain.^[70] This posed existential economic challenges for smaller software companies. As a result, copy protection systems were increasingly implemented, especially in games, which were the best-selling software category.^[171]

Operating System

The configuration and initialization of the computer upon startup or after a reset are handled by the operating system stored in read-only memory. The subroutines of this 16 KB Operating System (OS) manage various system processes, which can also be initiated by the user. These include performing input and output operations such as keyboard and joystick polling, floating-point calculations, processing system programs after interrupts, and providing a subroutine for generating various graphics modes. Compared to the Atari 400 and 800 models, the new operating system includes a diagnostic program for self-testing the computer’s functionality, such as the memory or sound generation.^[172] However, since the operating system, based on the Atari 1200XL, was not fully adapted for the Atari 800XL, the keyboard diagnostic displays keys that are only present on the Atari 1200XL.

The starting addresses of the individual subroutines are centralized in a Jump table. This table is located in the same memory area across all Atari computers to ensure compatibility with earlier and later operating system revisions. However, some programs, either due to programmers’ unfamiliarity or for copy protection purposes, do not use this table and instead directly call the relevant operating system subroutines. Since many of these subroutines in the Atari 800XL occupy different memory areas than in the Atari 400 and 800, calling them at the old, invalid memory addresses inevitably leads to program crashes. Consequently, some third-party programs do not run correctly on the Atari XL models.^[173] Atari released the Translator Disk to address these incompatibility issues, at least until the next reboot.^[174]

Alternative Operating Systems and Extensions

Shortly after the release of the XL computers, alternative and enhanced operating systems began to emerge, often in the form of add-on boards. These included, for example, Ramrod-XL with the EPROM-based Omnimon XL, optionally supplemented by the Fastchip (improved floating-point routines) and Omniview XL (80-character display via software).^[175] Later, additional alternative operating systems emerged, such as XOS/80 from Computer Support,^[176] Boss II from Alien Macroware,^[177] OS Controller Board,^[178] Expander,^[179] 6 System Switchbox,^[180] Diamond OS,^[181] and Ultra Speed Plus from Computer Software Services.^[182] These provided users with compatibility with older Atari 400 and 800 models, as well as enhanced functionalities, such as optimized floating-point and data transfer routines and powerful tools for system control and debugging.^[183][184] In West Germany, various versions of BiboMon were available starting in 1985,^[185] also in combination with the Turbo-Freezer XL.

Graphical User Interfaces

These extensions build on the standard operating system in conjunction with the disk operating system (DOS) and simplify user interaction. Actions that would otherwise require command-line input are now performed through menus in a clear, window-based environment. The operation of graphical elements is often facilitated by a freely movable, typically arrow-shaped cursor. Commercially available user interfaces included XL-TOS,^[186] Diamond GOS,^[187] and S.A.M. (Screen Aided Management), published for typing in the German Atari Magazin.^[188]

Programming Languages and Applications

If a task could not be accomplished with commercially available programs due to technical or economic reasons, or if, for example, new entertainment software was to be created, it had to be developed using appropriate programming languages. According to a late 1988 survey by the widely circulated magazine Antic Magazine, BASIC was by far the most commonly used programming language among Atari users.^[189]

Assembly Language

Creating fast-paced action games with many moving objects on the screen required optimal hardware utilization, particularly of the memory, in the early 1980s. In the home computer sector, this was only possible using assembly language with corresponding assembler programs. Assemblers were often delivered with an editor for entering program instructions ("source code") and frequently as a package with a debugger and disassembler for error analysis.

With the introduction of the Atari 800XL, sophisticated and powerful assemblers previously released for the Atari 400 and 800 became available. Some, such as the Synassembler from Synapse Software, were only compatible with the old operating system or required specific adaptations. Among the many assemblers offered, the MAC/65 from Optimized System Software was considered by far the best and most user-friendly. Combined with the Ultra Disassembler from Adventure International for program analysis, few wishes remained unfulfilled for ambitious program developers by late 1984.^[190] Well-known assemblers in West Germany included the 1985-released Atmas II by Peter Finzel^[191] and the Bibo-Assembler from Compy Shop.^[192]

Programming beginners often preferred the clearer and easier-to-use, though less powerful, high-level programming languages like BASIC.

Interpreter Languages

• 
  Atari BASIC input screen
• 
  Turbo-BASIC loading screen

Alongside Atari’s published BASIC in revisions B and C (from February 1985^[193]), several others were available: the then quasi-standard Microsoft BASIC and a downward-compatible product called BASIC XL from Optimized System Software. BASIC XL, in particular, offers advanced editing capabilities, simplified command structures, and includes many features not implemented in Atari or Microsoft BASIC. These include convenient use of sprites ("Player-Missile Graphics") through dedicated command words.^[194] By late 1985, two additional powerful programming languages for the Atari 800XL emerged: Advan BASIC^[195] and Turbo-BASIC XL.^[196]

In addition to BASIC in its various versions, languages suitable for educational purposes, such as Atari Logo and Atari PILOT, were available upon the Atari 800XL’s market launch and were often used in educational institutions. Supported by elements like turtle graphics, Logo, for example, enables a child-friendly and interactive introduction to programming fundamentals. Additional interpreter languages for the Atari 800XL included QS-Forth from Quality Software, Extended fig-Forth from APX,^[197] English Software Forth,^[198] Elcomp Forth,^[199] Go-Forth from Red Rat Software,^[200] and Inter-LISP/65 from Datasoft.^[201]

Compilers and Compiler Languages

The inherent limitations of interpreter programs, such as slow execution speed and high memory requirements, impacted their usability. These drawbacks could be mitigated by specialized programs called compilers, which generate executable machine programs that run without an interpreter, often allowing faster execution. For Atari BASIC, compilers such as ABC BASIC Compiler from Monarch Systems, Datasoft BASIC Compiler from Datasoft, and BASM from Computer Alliance were available.^[202] By late 1984, the BASIC compiler from MMG was considered the most powerful for the XL computers.^[190] The software range was further enhanced by compilers for Advan BASIC and Turbo-BASIC XL, released by late 1985.

Among the widely used compiler languages, C and Pascal had corresponding versions for the XL computers. These included Deep Blue C from Antic,^[203] C/65 from Optimized Systems Software,^[204] Lightspeed C from Clearstar Softechnologies,^[205] and DVC/65,^[206] as well as Atari Pascal from APX, Draper Pascal in various versions from Norman Draper,^[207] and Kyan Pascal in various versions from Kyan Software.^[208] The most powerful programming language, available exclusively for Atari computers, was Action! from Optimized System Software, combining elements of C and Pascal with commands tailored to Atari’s hardware.^[190] A unique compiler language among those available for 8-bit Atari computers was MASIC, released in early 1987 by Rätz and Eberle, designed solely for creating independent music subroutines for inclusion in games or demonstrations.^[209]

Application Software

By 1985, the software range for Atari 8-bit computers included, alongside programming languages for creating custom applications, a relatively small selection of pre-made commercial application software compared to its contemporary competitor, the Apple II.

Among the most powerful word processing programs at the Atari 800XL’s market entry were Atari Writer from Atari (Atari Schreiber in West Germany), Bank Street Writer from Broderbund, Letter Perfect from LJK Enterprises,^[210] and The Writer’s Tool from Optimized System Software. For accounting and other business tasks in the home, programs available by late 1984 included VisiCalc from Visicorp, The Home Accountant from Continental Software,^[210] Data Perfect from LJK Enterprise, Synapse’s programs Synfile+, Syncalc, Synstock, and Syntrend, and Complete Personal Accountant from Futurehouse. Additionally, numerous joystick-based drawing programs were available, such as Paint from Atari, Graphic Master and Micropainter from Datasoft, Moviemaker from Reston Software, and Fun with Art from Epyx.^[190] Highly rated programs for controlling sound output included the speech synthesis program S.A.M. – Software Automated Speech from Tronix and the Advanced Musicsystem from APX.^[211]

Throughout 1985, the software selection expanded with Print Shop from Broderbund, Paperclip from Batteries Included, Atariwriter+ from Atari, Austrotext from Austro.com, Proofreader from Atari, and StarTexter from Sybex-Verlag, adding powerful applications in layout and word processing.^[212] Databases and small business applications included Austrobase from Austro.com, Business Inventory System from CodeWriter, and Silent Butler from Atari.^[213] The selection of drawing programs expanded with Antic’s RAMbrandt and the Micro Illustrator from Koala Technologies,^[214] while music programs grew with MIDICom from Hybrid Arts, Music Studio from Activision, and SoftSynth from the German magazine Happy Computer.

In 1986, users interested in word processing and desktop publishing gained access to First Xlent Word Processor from Xlent Software^[215] and AwardWare from Hi Tech Expressions. For accounting, B/Graph from Ariola and Back to Basics Accounting System from Peachtree Software were released. New graphics programs included Blazing Paddles from Baudville, Design Master from Peter Finzel Productions, Envision from Antic Software, and Technicolor Dream from Red Rat Software. Hybrid Arts expanded its MIDI portfolio with MIDI Music System and Oasis. The German-produced Soundmachine also became available.^[216]

In 1987 and 1988, the range of applications was further expanded with LuxGraph XL, MiniOffice,^[217] Newsroom from Springboard Software, Print Star from AMC-Verlag, S.A.M. – Screen Aided Management from Atari Magazin, and SX Express! from Atari.

Educational Software

In line with the educational focus of the predecessor models Atari 400 and 800, a vast array of programs was available for computer-assisted learning and interactive knowledge assessment. The content is presented in a playful manner with increasing difficulty to keep learners motivated. Great emphasis is placed on age-appropriate presentation, ranging from young children to university students. For the youngest, animated stories with cartoon-like characters as tutors are often used; for teenagers, content is embedded in adventure or action-packed space games; for higher-level content aimed at students and adults, knowledge is typically presented in an encyclopedic format with subsequent testing and performance evaluation. By late 1984, over 100 titles covered learning areas such as reading and writing, foreign languages, mathematics, technology, music, geography, demography, typing schools, and computer science.^[218][219]

Well-known manufacturers included American Educational Computers, Atari, APX, Carousel Software, CBS Software, Walt Disney Productions, Dorsett Educational Systems, Edupro, Electronic Arts, The Learning Company, Maximus, Mindscape, PDI, Prentice Hall, Scholastic, Screenplay Computer Software, Sierra On-Line, Spinnaker Software, Sunburst Communications, Unicorn Software, and Xerox-Weekly Reader.^[220]

Games

Main article: List of Atari 8-bit computer games

A significant portion of the games usable with the Atari 800XL originated from 1979 to 1983 for the largely compatible predecessor models Atari 400 and 800. The supply of high-quality programs declined significantly after Atari’s acquisition by Jack Tramiel in July 1984 and his initially unclear future plans. Many software developers faced economic uncertainties and turned to more promising systems like the Commodore 64. This trend continued even after Atari’s economic recovery in early 1985, with only a few titles—mostly conversions—released in the U.S. from mid-1985 to 1987. Significant quantities of programs, particularly low-budget games, were released in Europe from late 1986, but large-scale software distribution collapsed there by late 1989. Subsequently, availability was limited to magazines and small mail-order retailers. Due to extensive computer sales in the Eastern Bloc and the resulting software demand, a distinct developer landscape emerged in Poland after 1989, with new companies like Laboratorium Komputerowe Avalon, Mirage Software, and A.S.F. producing and distributing over 140 games, with Mirage Software continuing until 1995.^[221]

Magazines

In the 1980s, alongside specialist books, computer magazines played a significant role for many home computer owners. These often monthly publications contained reviews of new products, programming tutorials, and software listings for users to type in. They also served as advertising and information platforms and facilitated contact with like-minded individuals.

In the English-speaking world, magazines specifically focused on Atari home computers included Antic, Analog Computing, Atari Connection, Atari Age, Atari User, Current Notes, and Page 6. Occasional articles and programs for Atari computers were also published in high-circulation magazines such as Byte Magazine, Compute!, and Creative Computing.

Emulation

After the end of the home computer era in the early 1990s and with the advent of powerful and affordable computing technology in the late 1990s, dedicated enthusiasts increasingly developed programs to emulate home computers and their peripherals. Using emulators, a single modern system with data images of the respective home computer programs was sufficient to play classic games from various systems. The rise of emulators spurred the transfer of otherwise potentially lost software to modern storage media, making a significant contribution to the preservation of digital culture.^[222]

The most powerful emulators for Windows and Linux systems include Atari++, Atari800Win Plus, Mess32,^[223] and Altirra.^[224]

Reception

Contemporary

Shortly after its release, the trade press unanimously praised the Atari 800XL for its high build quality, though opinions diverged regarding the quality of the keyboard and the external power supply. Reviewers also appreciated the wide selection of programs, particularly games, and the extensive range of peripherals. However, some noted that BASIC Revision B, intended to be bug-free, introduced new, albeit less severe, errors. The lack of full backward compatibility with the Atari 400 and 800 models was a common criticism, though Atari’s subsequent solution, the Translator Disk, was widely welcomed. There was also confusion over the absence of a connection option for standard cassette recorders, forcing users to purchase Atari’s proprietary devices. In the UK, some criticized the relatively high software prices.^[225] Overall, the performance specifications were convincing, though the system architecture was seen as somewhat dated. Nevertheless, it was considered among the best in the home computer sector:

Let’s face it, these new XL machines are nothing more than repackaged 800s. That does not change the fact that Atari home computers are still the most versatile graphics machines you can buy for less than five thousand dollars.

— ^[226]

Display case of the Atari Bit Byter User Club (A.B.B.U.C.) with various Atari home computers at the Games Convention (2008)

Following Atari’s acquisition by Jack Tramiel and the significant price reductions by late 1984, the Atari 800XL regained the attention of many reviewers. The high-circulation computer magazine Byte, for instance, largely echoed earlier reviews but additionally highlighted the now well-organized user community and emphasized the favorable price-performance ratio, making the Atari 800XL a bargain.^[227] The overwhelmingly positive perception associated with the price reductions culminated in mid-1985 with the Home Microcomputer Award 1985:

We feel the 800XL is a good computer, with a decent amount of memory, very good graphics and a good range of software that is no longer so expensive.

— ^[228]

Retrospective

In retrospect, the system architecture of Atari computers was unanimously regarded as groundbreaking and a pioneer for many later systems.^[229] Several authors noted that "production issues" and associated pre-Christmas delivery problems in 1983, caused by "internal changes at Atari," significantly diminished the Atari 800XL’s potential market dominance. Missed market shares primarily went to the already established Commodore 64, from which the initially relatively expensive Atari 800XL never recovered.^[230] Additionally, technical advantages of the Commodore, such as its colored sprites, were prerequisites for many gaming innovations, relegating the less capable Atari 800XL to a "shadow existence" from 1985 onward.^[231] Nevertheless, "Atari’s 8-bit series sold quite respectably on both sides of the Atlantic," but "not as well as it deserved."^[232]

The Atari 800XL is a permanent exhibit at the Oldenburg Computer Museum, among other locations.^[233]

Further reading

• Stanton, Jeffrey; Wells, Robert P.; Rochowansky, Sandra; Mellin, Michael (1984). Atari Software 1984. The Book Company. ISBN 0-201-16454-X.
• Reschke, Julian; Wiethoff, Andreas (1986). Das Atari Profibuch [The Atari Professional Book]. Düsseldorf: Sybex-Verlag. ISBN 3-88745-605-X.
• Eichler; Grohmann (1984). Atari 600XL/800XL Intern. Data Becker. ISBN 3-89011-053-3.
• Goldberg, Marty; Vendel, Curt (2012). Atari Inc. – Business is Fun. Syzygy Company Press. ISBN 978-0-9855974-0-5.

Notes

1. In the U.S., the price dropped to ~$180 (see Diane Curtis: Editorial. The Associated Press, November 13, 1984); in the UK, to £200 (see Atari 800XL Price Slashed. Popular Computing Weekly, December 6–12, 1984, pp. 1–2); in West Germany, to 650 DM (see Reinhard Weber: Ein kritischer Blick auf den Herausforderer. In: P.M. Computerheft, 12/84, p. 106).
2. In the UK, the price fell to ~£170 (see Atari plans up-market 800XL micro. Popular Computing Weekly, November 8–14, 1984, p. 1; Atari Price Cut in the US. Popular Computing Weekly, November 22–28, 1984, p. 5); in France, the SECAM version cost 2500 francs (see Atari en kit. Micro 7, November 1984, pp. 30–31).
3. Refers to the 48 KB Sinclair ZX Spectrum.
4. The C64 cost ~£200 in the UK and 600 DM in West Germany ("Geschäft ist Krieg" [Business is War]. Der Spiegel (50). 1984.). MSX computers cost at least £275.
5. The ATR-8000 was delivered with a Z80 microprocessor; an Intel 8088 was available as a separately purchasable add-on card.