Blackout

I realize it's been a long time since my last blog post, and so I'd like to start by apologizing for my long absence. Life, sometimes, takes us down unexpected paths and puts us face to face with challenges that require all our attention and strength.As some of you know, I am dealing with a health condition that requires brain surgery, scheduled for the next three months. This period of waiting and preparation has been an emotional journey, full...

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Inside the Macintosh: the memory.

Let's start from this post with a series of posts with technical "dissection" of the different areas of the Macintosh mainboard. It's very important to understand how the hardware works.Of course, a software emulator works differently from the real hardware, and many times it's a question of implementing tricks, especially when the emulator must run on a limited system such as a microcontroller.So I will take my time in studying components, I will...

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An experiment just for fun.

 I knew that "Digital" would enchant me. Especially for the fact that it gives me the opportunity to virtually replicate different areas of the Macintosh circuit to perform tests and understand how it works. Now I would like to do an experiment. In truth, I don't need to go so low level for the emulator I have to write, but I'm curious to see how far this circuit simulator goes. I want to try to implement the 64k-bit MT4264 DRAM memory...

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Bricks for this project, really?

I don't know if it's happened to you too, but when I study electronic diagrams it makes me want to "reconstruct" the circuit to see it work. It's as if your head starts to go faster in imagining that you already have all the components at hand, ready to be inserted into their respective sockets on the PCB. It is also frustrating to note that the transition from a scheme to a prototype is not so immediate, especially in my current condition, where...

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Diving deep in the Mac.

I've been diving online for days looking for technical information on the Apple Macintosh 128k hardware. In truth, I didn't find much, at least what I was looking for.I was studying the diagrams and photos of the motherboard that I found, and I understood that the "custom" chips have a crucial role in the functioning of the Mac. They are called "PAL", or "Programmable Array Logic", and are programmed from the factory with particular programs...

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