I started a new project. I’m building a clone of a 1979 British microcomputer.
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This time I’m using a different microprocessor and assembly technique. The CPU is the legendary MOSTEK 6502 that’s been used in many computers since the 1970’s such as the Apple II., early Commodores, Ataris, Nintendos and NASA space probes.
The computer is supposed to be interfaced through serial port. Without keyboard and display it needs a host computer with a serial monitor. In my case it will be a Macbook and the Arduino IDE or some other monitor. I plan to add keyboard and an LCD display or video output.
Why bother building a computer as old as me? Well, firstly it helps me to understand how computers work. It’s a simple beast with only 32K ROM to store software permanently, 16K RAM and a mere 2MHz click sleed. Keep in mind we’re talking about a nearly four decade old processor! It’s simple enough to understand and build. Also, I find technology increasingly complex. I’ve been yearning for something simple that I can create and understand. The processor consists of only 3,500 transistors as opposed to the CPU in my laptop with it’s 700 million transistors (or the graphics card with 1,7 billion ones!). The 6502 is 200,000 times simpler!

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The board with wire the sockets glued on.

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The sockets were glued with hot glue gun. Not very elegant but effective and fast.

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The back plane with the sockets and the wire wrap tool on the right. The white labels help to identify the socket pins.

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