Atari 1090
| Atari 1090 XL Expansion System | |
|---|---|
 |
|
| A 1090 without its top cover, behind an Atari 800XL and beside two 1050 drives | |
| Manufacturer | Atari, Inc. (prototypes only) |
| Type | Expansion chassis |
| Interface | Parallel Bus Interface (PBI)[1] |
| Compatible | Atari 600XL, Atari 800XL; also the unreleased 1400XL and 1450XLD[1] |
The Atari 1090 XL Expansion System is an expansion chassis that Atari, Inc. designed in 1983 and 1984 for the XL computers. It plugs into the Parallel Bus Interface on the back of the Atari 600XL or Atari 800XL and holds expansion cards.[1][2] Atari showed it at the Consumer Electronics Show in June 1983 and again in June 1984, but it was never sold. Only a handful of prototypes are known.[1][3]
Announcement and specification
[edit | edit source]Atari announced the unit on 5 June 1983 as the "ATARI Expansion Box", alongside the CP/M add-on module and the 64K memory module for the 600XL (which became the Atari 1064). The press release gave it eight expansion slots, two RS-232 ports and a bi-directional parallel bus, and said the devices would be available in the fourth quarter at prices not yet announced.[4]
By the time it was called the 1090 XL Expansion System, the specification had changed. The comp.sys.atari.8bit FAQ describes it as plugging into the PBI to provide two RS-232-C serial ports, one Centronics-type parallel output port and five internal 8-bit PBI card slots, and says it was intended to replace the Atari 850 interface.[1] The Atari Museum gives the same five slots and adds that:[2]
- the first specification had eight slots, including an SIO card so that the 800 and 1200XL could use the unit through an external buffer box called the "Julie FIFO";
- a control line was added to the bus so that a bus-mastering card, such as a different processor, could take over the computer; the museum names an 8086 for IBM compatibility or a 65816 as possibilities;
- the XL Expansion System technical specification is dated 11 May 1984.
Cards
[edit | edit source]The FAQ identifies three prototype cards: the 1066 CP/M card (a card version of the CP/M add-on module), an 80-column video card, and a 64 KB RAM card that by June 1984 was to ship with the 1090.[1] The Atari Museum lists more card specifications, all of which reached the prototype stage: the 64KMR RAM card, the 80-column video card, the Z80 CP/M card, a serial and parallel card, an X10/BSR home-automation control card and a prototyping card. It adds that the "AMY" sound processor was designed to work in the 1090.[2]
What survives
[edit | edit source]- The FAQ says a handful of prototypes exist and that few, if any, working prototype cards do.[1]
- According to the Atari Museum, Best Electronics had a large supply of 1090 chassis and 64K memory cards in the 1990s, bought in Atari Corp.'s parts sales, and sold them cheaply without the metal case cover. A 1090 with a 64K card fitted adds 64 KB to an XL computer.[2]
- The museum holds a 1066 Z80 CP/M card, untested because no software or drivers survive, and a partly assembled 80-column board, which cannot be finished because no schematics survive. It reports that the National Videogame Museum in Texas has a 1090 with almost all of the proposed cards.[2]
Reproductions
[edit | edit source]In 2024 Brian Reifsnyder and Ken Ames began selling a newly made 1090 board through Tindie, with new cards: an 80-column card with HDMI output, a 320K RAM card and a card for the CX85 numeric keypad. AtariProjects reports that it runs from a 9 V adaptor of the kind used with the Atari 800 and 1050, connects to the PBI by a ribbon cable, and was then supported on the XL computers, with XE support still being developed.[5]
Documentation
[edit | edit source]- Atari press release, 5 June 1983: the announcement of the Expansion Box, the CP/M module and the 64K module.
- The Atari Museum's 1090 page lists the XL Expansion System technical specification (11 May 1984), "SW Implementation of Parallel Devices" (22 May 1984), the 1090 schematics and mechanical drawings, the device registers, a general-purpose interface example and the parallel device RAM specification (30 April 1984). These are not hosted here.[2]
Related pages
[edit | edit source]References
[edit | edit source]- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Michael D. Current (ed.), Atari 8-Bit Computers: Frequently Asked Questions, section 6.1.3, "What were the CP/M Add-On module and 1090 XL Expansion System?". atarimania.com. Community reference.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Atari Museum (Curt Vendel), "Atari XL Series Computers – 1090XL". Collection and archive notes.
- ↑ Michael D. Current (ed.), Atari 8-Bit Computers: Frequently Asked Questions, section 11.1 (history), June 1983 and June 3, 1984 entries. faqs.org. Community reference.
- ↑ Atari, Inc., press release, "CP/M Module Leads Trio of Advanced Expansion Devices for Atari Home Computers", Sunnyvale, 5 June 1983, two pages. Hosted here as File:Atari press release, CP-M module and expansion devices (5 June 1983).pdf; source Internet Archive item 19830605CPMModuleLeadsTrio (David Ahl collection).
- ↑ AtariProjects, "Purchase a Replica of the 1090 XL Expansion System for the Atari XL and XE 8-Bit Computers", 1 March 2024. Community write-up.