Apple Cloner "DosFox" Returns with the First Apple Macintosh Plus Compatible Built in 34 Years

Pseudonymous vintage computing enthusiast "DosFox" is back replicating the work of Apple engineers from decades ago — and has built the first new Apple Macintosh Plus compatible for 34 years, following on from an earlier project to clone the Apple Lisa.

"This has been an absolutely insane project. Theoretically this project is even older than the Lisa project — I only built the Lisa as I couldn't build a Macintosh," DosFox recalls. "Almost exactly a year after the Apple Lisa clone fired up for the first time, the Mac Plus clone has also fired up."

Apple launched the original Macintosh in 1984, as a follow-up to the Apple Lisa released in 1983 — and generally recognized as the first personal computer to feature a graphical user interface and aimed at a mass-market audience, having taken inspiration from the business-oriented Xerox Alto. The Macintosh Plus was the third in the range, after the original Macintosh was succeeded by the Macintosh XL in 1985, bringing a range of improvements including a stock 1MB of RAM — upgradeable, for the first time in the company's history, to 4MB using SIMM modules.

All original Macintosh designs, which put the computer inside an all-in-one housing with a compact CRT display, have long been discontinued — but their PCBs are simple enough and their components well-understood enough that it's possible for someone suitably committed to reverse-engineer the design and create a clone, which is exactly what DosFox has done.

The resulting clone is fully compatible with software and hardware designed for a real Macintosh Plus, though while the clone has been successfully booted there are a few wrinkles still to be ironed out. "The biggest one is that — despite working with the [Macintosh] SE logic board and has been reported to work with the Plus — my [Raspberry Pi Pico] scan converter [display output board] isn't working."

Despite this, the project is a definite success, and now makes it possible for enthusiasts to build their own Apple Macintosh Plus clones alongside Apple Lisa clones — something that would have given Apple considerable cause for concern, had this still been the 1980s.

More information on the project is available in DosFox's Mastodon thread.