
The Visual 6502 - sebkomianos
http://www.visual6502.org/JSSim/index.html
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0xcde4c3db
This is still cool, but has anything updated lately? I don't see anything
newer than the Atari 2600 simulation, but I also can't get the "Recent
Changes" page on the wiki to show anything, so I might be missing something.

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snori74
Well, there's a deceptive advert on the page now...

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mavhc
One of the most interesting parts I found was it's not created from a spec,
but from scanning and etching an actual chip, useful work for all the chips
without complete documentation.

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amelius
The 6502 only had a few layers of metal connections. I'm not sure how well the
etching would work on modern processors (though in theory of course it should
be possible).

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sebkomianos
I found this while searching for any kind of material that could help me
understand how computers work, in the sense of how the flow of electrons
becomes stuff on my screen. It's a question that neither my academic nor my
personal studies have answered so any suggestions on what to read/watch/study
would be more than appreciated!

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0xcde4c3db
It really depends on how deep you want to go. This is a topic that requires
tunneling through surprisingly few layers before you hit quantum mechanics. I
haven't gone through it, but "From NAND to Tetris" [0] is often recommended
these days. My own education in these topics was a lot less organized and took
quite a few years to really click.

Thinking about "the flow of electrons" is more of an analog topic, and that
class of behavior is usually treated as non-ideal inefficiency for purposes of
digital logic systems. This stuff is extremely important in figuring out how
fast you can make things go when designing a real chip/board, but the gory
details are fairly unimportant to computer architecture concepts beyond
accepting the more abstract models of gate delay (each gate a signal passes
through delays it) [1] and fanout (the more inputs you drive with a given
output, the slower those inputs are switched) [2].

[0]: [http://nand2tetris.org/course.php](http://nand2tetris.org/course.php)
[1]:
[https://en.wikipedia.org/wiki/Propagation_delay#Electronics](https://en.wikipedia.org/wiki/Propagation_delay#Electronics)
[2]: [https://en.wikipedia.org/wiki/Fan-
out](https://en.wikipedia.org/wiki/Fan-out)

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sebkomianos
I wouldn't call my "education" on the topic organized either - I wouldn't call
it education anyway, to be honest. "From NAND to Tetris" sounded like what I
wanted but once I skimmed through the material it looks like it not as
abstract-less as I want to go.

Thanks for the reply anyway!

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Quiark
First time I see this. I understand jack of it but it's really amazing. On one
side, it seems not too different from an abacus (it's just a machine!), on the
other side there's a connection to the processor that I use right now. Very
cool.

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niklasni1
Digital electronics means thinking of a transistor as a switch. It's got three
terminals, if there's a positive voltage on the control terminal then the
other two are connected and power can flow through it. That's basically it.

If you connect billions of switches in the right pattern you get a computer.
Billions of little switches clicking on and off, no more, no less. No pixies
or magic dust involved.

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niklasni1
(OK, I said billions. Thousands will do.)

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euske
Pro tip: you could simply avoid a dupe submission by searching.

[https://hn.algolia.com/?q=visual+6502](https://hn.algolia.com/?q=visual+6502)

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linker3000
Or how about the submission process checks and reports whether links have been
previously submitted.

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laumars
HN does perform duplicate URI checks, where duplicated submissions count as an
upvote towards the original submission rather than a new thread. However HN
also allows re-submissions after a certain time period has passed, which I
think is what happened here since the next newest instance I can find is ~4
months old.

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detaro
I think the time limit is longer, but the exact same URL has been posted last
a year ago, the submissions inbetween weren't recognized as dupes because they
have different URLs.

