Revival of a classic: an engineer created a clone of the 1984 Apple Macintosh Plus

A vintage computer enthusiast has created the first new clone compatible with the Apple Macintosh Plus in 34 years. The last Macintosh Plus (before this one) was manufactured in 1990.

The original Macintosh Plus was released in 1984 after the Apple Lisa. It is widely known as the first PC with a graphical user interface and was aimed at a mass audience. The computer had 1 MB of RAM, which could be expanded to 4 MB using SIMM modules. It was shipped as a one-piece design that contained a computer and a compact CRT display in one case.

The electrical engineer adds this clone to his previous work on cloning Apple Lisa, but says the work is not yet complete. The enthusiast claims that he has been trying to bring this project to completion for years.

Apparently, the creation of Lisa was the necessary impetus, as he successfully booted the Macintosh Plus clone almost exactly one year after first booting Lisa.

The project required a fair amount of trial and error, and there is still work to be done. One of the integrated circuits on the original Macintosh Plus board was incorrectly labeled as 74LS257, when in fact it was model 74F253. In addition, the engineer is still trying to recover the Sony SND Plus chip that controls the sound amplification and power reset.

It also turned out that even though the Raspberry Pi Pico scan converter works with the Macintosh Plus, it cannot get any video from it. To boot up and see if the clone was working, I had to use the AppleTalk remote control software Timbuktu to access the ancient clone.

Nevertheless, the project is considered a success because it was possible to create a clone that is fully compatible with any software or hardware originally designed for the real Macintosh Plus. Once the project is polished, the author will likely release schematics and instructions for other enthusiasts to replicate his efforts.

Source: tomshardware