how do i design the schematics for a motherboard using 1 or possiblly multiple processors for use in computers ?

i want to know how to design the schematics to build things such as 8-bit to 64-bit computers (and possibly video game systems E.G. atari 2600 clone) one thing specifically is what components such as capacitors, diodes, etc. would be needed and how to  properly locate them and also whether to use standard pc ram or to use something different. another issue is what kind  of circuitry is necessary for a processor's access to memory and how multiple processors could access one pool of memory. i would like to say that these are generic issues relating to future ideas which i want to become reality

AndyGadget6 years ago
That's one of those questions that if you have to ask it, you haven't a chance of doing it with your current knowledge.  Designing a whole current specification computer from scratch is an absolutely monumental task which would be undertaken by a large group of specialists rather than an individual.
THIS looks amazingly similar to something I knocked up as a home project in the early 80's.  This is a "simple" 8085 based microcomputer (only mine had hexadecimal displays!).
Moore's observation states roughly that the complexity of computer curcuitry doubles every two years, which means that today's computers are very approximately 2^14 more powerful.  That's around 16 thousand times than the design linked. (In fact more, as what I built was already well off 'state of the art'.)

Start off with the basics - Discrete logic and basic computer theory and learn a programming language.  Get to grips with a microcontroller family - They're great fun.  Play around with input and output devices.   Move on to building a small system using LSI chips for functions like the video controller and input / output control. 
You mention the Atari 2600 - Building something similar is achievable with a bit of time and effort.

I have a yen to build the Apollo Guidance computer Block 1 here:


Amazing. For a time, AGC development took 60% of the entire US production of TTL NOR gates
lemonie6 years ago

If you don't want to buy something, clone something.
By that I mean copy an existing board by reverse-engineering, or find a schematic and component list on t'internet.

frollard6 years ago
I don't want to dash your hopes with a pessimistic view, but you really REALLY need to start with the extremely basic - start from simple logic, schematics, and parts. An entire computer is literally thousands of connections, each one vital.

There are schematics out there for a DIY 8088 computer, all done with wire wrap. A good learning tool, but a tonne of work.

Realistically, with a computer science/electrical engineering degree, lots of money for parts and tools, etc...it's a mammoth project. Without them, its downright ridiculous. I don't know your level of expertise, thus I don't denounce your project as madness. If it's anything like it sounds, it would be akin to building a supercar from raw materials. It can be done, but I wouldn't count on it.