I have been reading about wires in Wikipedia
What am I doing?
I am reading about wires thinking that I could by my wide knowledge with bunch of reading be capable of creating simple 8-bit or 16-bit CPU
What I know?
Proximity effect and Skin effect effect wires, I know how we can produce these, but I don't understand how they actually construct.
What I want?
I saw many projects on making simple 8-bit CPUs, they use traditional Stranded wires, however, I am not sure what is the frequency of that CPU, but let's say I am trying to make 1Mhz CPU, what kind of cables do I need? Litz wires seem to be used in >500Khz conditions
Best Answer
Because you are carrying logic-level signals (a few volts and a few milliamps) you can use pretty much anything you want. I've made 20 MHz logic using 30 gauge solid wire - wire-wrap, to be precise, and it worked fine.
What you have to start being careful about are termination and cross-talk.
When running a wire much more than the distance equivalent of your rise and fall times (typically a foot or so) you must consider using twisted pair and termination to avoid signal/power reflections.
When running many signals together, if you bundle the wires tightly, a transition on one will be radiated and picked up by a neighbor. Separating such wires and making sure they do not run closely in parallel is a good start, but shielding each from its neighbor may be necessary.
As I recall, the generally accepted upper limit on wire-wrap boards, which do use separate wires, is about 100 MHz, although this requires care with terminations.