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Harry Porter's Relay Computer

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This might sound a little odd, but am I the only one who originally read that as Harry "Potter"?

Also, the video is quite nice!

nope ;)

No. But I was wondering how an electromechanical computer would fit into that particular fictional universe.

I dimly recall trying to figure out how to make modern(ish) conveniences, like flashlights or televisions, under D&D rules. An imaginative person (i.e., not me) could probably use the "building technology on top of a magic-based world" theme as the basis for some good stories.

Of course, there's probably some corollary of Rule 34 for fictional world-building, meaning there's already thousands of books out there with this theme. If anybody knows of some well-written ones, I'd be interested in having some new (good) fiction to read.

The one that springs most immediately to mind is "Wizard's Bane" by Rick Cook, which involves somebody making a programming language out of small spells which could be used to make more complex ones, but the book wasn't actually that good.

Much better written (and very popular) is "Harry Potter and the Methods of Rationality", which you can find here:

http://www.fanfiction.net/s/5782108/1/Harry_Potter_and_the_M...

...Or in a variety of ebook formats from the author page.

Diane Duane's "Young Wizards" series never reveals much about the workings of its magic system, but it's made pretty clear that using magic effectively is mostly a matter of describing precisely what you want to happen, and closely akin to engineering. They're good books, and I like the idea of non-mysterious magic that you may have to debug before it works right.

Here's another one (smaller, but more messy!): http://www.kilian-leonhardt.de/relaiscomputer/pics/pic4.htm

I also bought a neat little 4-bit relais computer from this person (Kilian Leonhardt). It's got just enough program memory to do a multiplication algorithm in.

Having seen it in action in person, I found the sound quite astonishing. It has noticeable patterns.

Yes, the video is mesmerizing. Reminds me of sticking an AM radio into the guts of a 6502 based computer in order to debug a crash to determine whether it was looping or had hit an illegal opcode (the sounds are noticeably distinct).

Rhythmically, it sounds exactly like a hippie drum circle.

EDIT: To whomever downvoted me, I like hippie drum circles.

All together now:

     Load a word, to A, load a woord!
     Increment PC, incremeeent!
     Load the next opcooode, load it iiin!
     Oh, Loooord, now decooode!

The sound reminded me of piston contraptions in minecraft...

If you like this, check out Jon Stanley's similar but smaller Relay Computer Two[1]. The page gives a highly detailed explanation of how it all works including complete circuit and logic diagrams.

[1]: http://www.electronixandmore.com/project/relaycomputertwo/in...

The only part where he cheated as far as I can see is the memory, that's a static RAM chip. All the rest of it is relays, it runs at 6(!) Hz.

The video is quite amazing.

Tech specs:

5Hz clock cycle.

8 general purpose registers.

32kb of memory.

19 instruction non pipelined architecture.

"not fast, but lights blink and it makes noise."

Respect :)

damn i saw it and the potter fan inside me woke up, i clicked it and.. bummer. but the vid was nice :)

The video is way cool-- makes me think of Intel's video for their 3D transistor where they shrank (who?) down to transistor size to demo it.

Just imagine somebody shrunk to fit inside a CPU, giving exactly the same tour.

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