For some years the fashion has been for “mini” consoles, and some companies sometimes also offer computers in the same style as for the Commodore 64 or Amiga. And a hacker, James Lewis, is trying to do the same for the Apple IIe using the Mega-II chip from an Apple IIgs.
A personal project
Let’s be clear: Apple isn’t going to sell a ‘mini’ Apple II, the company isn’t exactly known for its love of nostalgia, and it’s unlikely to license the Apple II. The project is purely educational and is based on a kind of received idea: the Mega-II chip would be equivalent to an Apple IIe ” we chipped “.
Apple IIe and Apple IIgs
The Mega-II chip appeared with the Apple IIgs, an improved model, with a 16-bit processor and a new architecture. To run older generation programs (8-bit Apple II), Apple has integrated an internal chip, Mega-II, on the motherboard. You’ll often see it’s the equivalent of an Apple IIe on a single chip, but James’ edit shows that’s not the case. In reality, the chip controls frequencies, memory, some of the I/O, and contains the equivalent of an “80 column” board, but replacing an Apple IIe still requires several things, such as a CPU, a ROM, and RAM .
And indeed, James’ analysis shows that the Apple IIgs actually take care of much of the backward compatibility, leaving only a (small) portion of the functions to the Mega-II. There is also an improved version of the Mega-II (Gemini) in another Apple product: the Apple IIe Compatibility Board for the Macintosh LC. It allows you to run Apple II programs on a Mac without direct emulation: it contains the equivalent of an Apple IIe.
An Apple IIe mini boots up
The idea is therefore to create an Apple IIe with the Mega-II chip as a base. The prototype contains 3 compact boards: one integrating the Mega-II chip – to be restored in an Apple IIgs -, another with the processor (a 65C02, a development of the original 6502) and a ROM (containing code belonging to Apple ) and a final one that controls the video, and the goal is – in the long term – to use an HDMI output.
So far, the kit is still pretty limited: the Apple IIe starts… and that’s it. The keyboard is actually a bit complicated to integrate and has its own ROM and is currently emulated with a Raspberry Pi Pico. The next steps will consist of reducing the number of cables and managing the various components of an Apple IIe, such as those needed for storage.
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