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Not as a verified, off-the-shelf upgrade. Atari planned a Z80 CP/M card for its 1090XL expansion system, but the 1090XL never reached retail, and the Atari Museum says the card was not tested because its software drivers could not be found. A modern manual documents a remake design, but does not establish that a complete working setup is currently available.
What was the Atari 1090XL?
The 1090XL was a planned expansion chassis for Atari XL computers, including the 600XL and 800XL. It connected through the XL Parallel Bus Interface (PBI) and was designed with five 8-bit PBI expansion slots. Atari’s design also included a bus-mastering control line intended to let an alternate-CPU card take control of the computer’s bus. The 1090XL did not reach retail shelves, according to the Atari Museum’s 1090XL overview.
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The proposed cards show the system’s intended scope: memory expansion, 80-column video, serial and parallel I/O, home automation, prototyping, and a Z80 CP/M board. These were planned expansion options, not a set of retail upgrades for owners to install.
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The Z80 card for the 1090XL was designated the Atari 1066. The Atari Museum’s 1066 card page identifies a Zilog Z-80 processor and support circuitry. The Museum says the card has not been tested because software drivers have not been found. It also describes CP/M operation with an 80-column card as a reported expectation, not as a demonstrated, working configuration.
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The 1066 should not be confused with the Atari 1060 CP/M Add-on, also known internally as Sweet-Pea. That was a separate external-unit concept. The Atarimania Atari 8-bit FAQ says the 1060 was shown at the June 1983 Consumer Electronics Show and was planned around a 4 MHz Z-80A, 64 KiB of RAM, CP/M 2.2, and 80-column display capability. Atari confirmed its cancellation in January 1984, before it shipped.
| System | Form factor | Planned relationship to the Atari | Evidence status |
|---|---|---|---|
| 1060 CP/M Add-on (Sweet-Pea) | External unit | Standalone add-on concept for CP/M use; planned with a 4 MHz Z-80A, 64 KiB RAM, CP/M 2.2, and 80-column display capability (Atarimania FAQ). | Cancelled before shipment, according to the Atarimania FAQ. |
| 1066 Z80 CP/M board | Expansion card for the 1090XL’s PBI chassis | Designed to add a Z80-based CP/M capability; the Atari Museum reports that an 80-column card was expected for display. | Not tested because drivers were not found; the 1090XL itself did not reach retail (Atari Museum). |
What a modern 1090XL remake manual describes
A modern 1090XL Expansion Card Instruction Manual describes a Z-80 CP/M card with 64 KiB of RAM for its processor. According to the manual, the card needs a CP/M boot disk that includes software for using Atari I/O as well as the operating system; without that disk, the card remains dormant.
Those instructions document a remake design, not proof of a tested setup or current product availability. They also should not be treated as a complete specification for the original 1066 prototype: remake-specific details may not apply to it. The available documentation does not establish which 600XL or 800XL configurations work, whether a complete kit is currently sold, or whether the described card and boot disk operate together successfully.
What this means for 600XL and 800XL owners
The 1090XL is best understood as a planned route to CP/M on an Atari XL, not as a confirmed upgrade that an owner can simply buy and install. The historical 1060 was cancelled, the 1090XL was not a retail product, and the Museum’s 1066 record lacks the drivers needed to test the card. The modern manual is useful evidence of a remake design and its stated boot-disk requirement, but by itself it does not verify a working, available system.
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