
C64 Memory Map - ingve
https://www.pagetable.com/?p=1397
======
dvduval
Ah, this reminds me of my first computer, the Vic 20. I was fascinated by all
this. unfortunately I didn't apply myself and learn what all of this meant at
that time.

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kyberias
Please let the BROWSER show the scroll-bars. Now it's fairly unusable.

~~~
andai

      div.disassembly_container_no_dec {
          overflow: initial;
      }

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alphaBetaGamma
If I remember correctly, the system calls where indirect jumps where the
address of the jump was in _ram_ (it had been copied from the rom on startup):
it was designed to you could hijack system calls and modify their behavior.
This blew my mind as a teenager.

I wish modern system where still designed like that...

~~~
warpspin
Halfway correctly ;-)

There were a handful of pointers to the routines to use for BASIC execution in
RAM starting at address $300, which could be pointed elsewhere for BASIC
extenders or to redirect IRQs. Apart from that, most syscall addresses where
in ROM.

It allowed disabling parts of the ROM though to access the full RAM. That way
you could rewrite the real jump addresses, bypassing the ROM completely.

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andi999
I shd dig through this sometime. I remember the Basic Rom to be 8kb and the
whatever it is called IO? Also 8kb. A command takes 2-3 bytes so in less then
about 7000 commands it is possible to implement a full operating systen with
basic. I still (and more and more so) find this unbelievably efficient.

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egypturnash
There's no horizontal scrollbar for me on Safari, which kind of makes
comparing different takes on each address impossible unless you have four
monitors to stretch this across. Or Firefox or Chrome, now that I check it on
them. (OSX 10.14.6, Safari 13.1, FF 76.0.1, Chrome 81.0.4044.13)

~~~
wvenable
Going in the CSS and removing "overflow: scroll" from
"div.disassembly_container_no_dec" makes it scroll horizonally and vertically
properly.

~~~
userbinator
Whenever I find a site with good information but horrible readability, I turn
off the CSS. That often makes it look bland, but it becomes far more readable
--- more like a book. Some browsers have a "reader mode" which does a similar
thing. Sometimes I may send the author an email about it.

~~~
andai
What do you use to toggle CSS? Does the same UI work for JS too?

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c64-4-eva
What a blast from the past. It was always difficult to access the RAM
underneath the ROM above 48K. You could but you'd have no system calls
available.

~~~
jimsmart
> You could but you'd have no system calls available.

True, but to be fair though, games developers had little (if any) need for
system calls into the kernel, and we'd often make use of that RAM.

Not that I recall exactly what we were using it for, it varied game to game —
disclaimer: several published C64 games, but I've not messed with any of this
since the early 90s!

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Sephiroth87
That’s very nicely done, thank you!

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Luc
When I submitted this yesterday the 'Ultimate' at the beginning of the title
was also automatically removed. I thought I had made a copy-and-paste error at
first. Weird.

~~~
goodside
HN has a long history of de-sensationalizing link titles, both through
automated substitutions and manual changes from moderators. Some aspects of
this are in the "News Guidelines" at
[https://news.ycombinator.com/newsguidelines.html](https://news.ycombinator.com/newsguidelines.html):

> Please don't do things to make titles stand out, like using uppercase or
> exclamation points, or saying how great an article is. It's implicit in
> submitting something that you think it's important.

> If the title includes the name of the site, please take it out, because the
> site name will be displayed after the link.

> If you submit a video or pdf, please warn us by appending [video] or [pdf]
> to the title.

> If the title begins with a number or number + gratuitous adjective, we'd
> appreciate it if you'd crop it. E.g. translate "10 Ways To Do X" to "How To
> Do X," and "14 Amazing Ys" to "Ys." Exception: when the number is
> meaningful, e.g. "The 5 Platonic Solids."

> Otherwise please use the original title, unless it is misleading or
> linkbait; don't editorialize.

I sometimes wish the guidelines were a bit more transparent, e.g. confirming
with the submitter that the meaning of the title hasn't been harmed by an
overzealous replacement. The edits are clearly a net positive, but they're
confusing when they go wrong.

A few months ago @petercooper made an app for tracking live changes to HN
headlines, which gives a sense of how frequent they are:
[https://hackernewstitles.netlify.app/](https://hackernewstitles.netlify.app/)

~~~
dang
If the software changes a title you can always use 'edit' to change the
change.

Software changes don't show up in Peter's app of course, since they're done at
submission time.

