He is trying to make an Apple IIe “mini” with an Apple chip

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.

The Mega-II chip.

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 .

A montage that is still a bit raw (from ?).

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.

It starts.

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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