TTL homebrew CPUs

[Grant Stockly]

At 05:04 AM 7/6/2007, you wrote:

>I've been thinking more and more this last week about designing a CPU to 
>be built from TTL logic ICs, purely as an interesting exercise.
>
>I'm thinking of a microprogrammed design with a pretty minimal register 
>count - but as speed is never going to be a defining aspect anyway using 
>commodity TTL, I'm thinking of going for a bit-serial ALU to keep the 
>parts count down. Keeping the raw components pretty basic is another 
>desired goal - no custom off-the-shelf ALU chips, gate arrays etc.
>
>Questions: have any others on here done stuff like this, or have any 
>pointers to good resources? I'm learning as I go along here, flicking 
>through technical manuals for 8-bit CPUs etc. and gleaning what I can from 
>the web.
>
>MAGIC-1 is about the most comprehensive online resource I've found so far, 
>but I believe it's a pure parallel core, and plus it's *way* more 
>feature-rich that what I'm aiming for. I'm not interested in running 
>UNIX-a-like software, or giving it hard drive interfaces or network stacks 
>- I just think it'd perhaps be fun to design and later build something 
>from scratch to do basic computation.

In the near future I will be supplying bare bones Kenbak parts, like a 
PCB.  First I need to make back the initial investment and engineering costs.

Just an idea...

Grant