Two Stop Bitsnew | comments | tags | ask | submitlogin
  • masswerk 26 days ago | parent | on: Why is there a "small house" in IBM's Code page 43...
    My suggestion: it's the "mode change" code/character found in various IBM punchcard encodings, punch 11-8-7, represented by an upper-case delta.

    Rendering this slightly differently from the regular Greek letter, would make sense, I guess. This may also explain the varying representations in the manuals: some would represent this like in common EBCDIC charts, as a delta, while others would refer to it as represented in the actual on-screen character set.

    (There is also the rather common problem with special characters in manuals, where the font used for the chart doesn't comprehend the particular glyph, giving rise to alternative, often more abstract representations, as these symbols were drawn in later.)

    reply
  • masswerk 37 days ago | parent | on: Commodore PET 2001 Series
    BTW, there are now a few new debugging options.

    (Bracketed address ranges additionally to breakpoints, which trigger either as PC enters or exits, optional trap for "illegal instructions", and a continuous CPU log, so you may find out how you wound up in a trap, regardless wat the regular trace was set to. — In essence, all you may need to trace some run away code.)

    reply
  • masswerk 45 days ago | parent | on: Commodore PET 2001 Series
    BTW, here's a link to a more compact overview of the various blog posts:

    https://www.masswerk.at/nowgobang/list/

    • bmonkey325 45 days ago
      Nice. A huge treasure trove of info
  • masswerk 116 days ago | parent | on: PET Globe demo
    It's even better: the crucial parts of the source code are in the article, in plain sight! :-)
  • masswerk 119 days ago | parent | on: PET Globe demo
    [Author of the blog post here.]

    For a more old-school approach, see "Sphere Mapping" by Frédéric Goset.

    http://fredericgoset.ovh/informatique/oldschool/en/spheremap...

    (This may well be why the LLM "knows" about this. May be interesting to compare approaches and variable names. – It's also linked in the article.)

    • bmonkey325 119 days ago
      nice article and nice link. if you want to see videos of the result:

      https://www.youtube.com/watch?v=_aTh5_FTasg

    • qingcharles 119 days ago
      Definitely. I'd actually just read that link before I asked GPT to write the code. I wondered how much of that page, and the various StackOverflow questions on this topic it was combining to create its code.
  • masswerk 210 days ago | parent | on: Wasm translation of PDP-7 Space Travel
    Great! Maybe add the controls and gameplay description to the hosted page, so that users may learn how to interact?
  • masswerk 279 days ago | parent | on: POLF - a 3D game for the Commodore PET
    You can play it in online emulation here:

    1) POLF, PET 2001N with graphics keyboard (turn left/right is actually "," and ";"):

    https://www.masswerk.at/pet/?prg=polf&rom=4&ram=16k&...

    2) POLF, PET 2001/B with business keyboard:

    https://www.masswerk.at/pet/?prg=polf&rom=4b&ram=16k...

    • bmonkey325 278 days ago
      Thanks for this. After playing this for a bit. It feels 3D. I thought my mind was filling in from wolfenstein watching the video. But live - different story. Legit. Cool. 😎
  • masswerk 311 days ago | parent | on: In defense of an old pixel
    The link "Punched-Card Typography" at the bottom really should lead to the original site, which, besides interactive animations [1][2], includes a font editor [3].

    [1] https://www.masswerk.at/misc/card-punch-typography/

    [2] https://www.masswerk.at/misc/card-punch-typography/part2-ibm...

    [3] https://www.masswerk.at/misc/card-punch-typography/editor.ht...

  • masswerk 339 days ago | parent | on: Internal NeXT video
    Notably, this was already much the same situation for the early "professional GUI", like the Xerox Star, or Perq (and, to a certain extent, the LISA, aiming at the low end of that market, centering on general productivity). In the early 1980s, it was really too early for this, without major investments in opening up that market in the first place. (In other words, it was really about the imaginary of what an organization or business was and how it should operate. As it turned out, nothing in this was self-explanatory.) At this stage, Jobs is clearly hoping for that market developing its own momentum, as organizations were becoming aware of the technology. Nevertheless, NeXt still failed, like its predecessors.

    I guess, in the end, nothing substantial really became of that market, with evolving capabilities from the general productivity market eventually swallowing that segment. Which is also pretty much the story of NeXt Step's afterlife in OS X. Notably, and not entirely without irony, the professional GUI was a major prerequisite for this development kicking off, for having commercial GUIs and powerful general productivity appliances, at all, but it was still pretty much doomed to fail, right from the beginning.

    • bmonkey325 339 days ago
      Just adding to your statements …

      It was too damned expensive and wasn’t colour. I saw the demo and thought holy #@$&! But even a Mac IIfx was about half the cost. Colour and had “pro” software. PCs were half of that and ran word and word perfect (and those janky keyboard templates) or 123 and did what business wanted. AutoCAD and pro engineer were about the most pro apps on PCs that anyone ran.

  • masswerk 342 days ago | parent | on: I Was a 1980s Teenage Programmer Part 3: MSX-2
    > My father had switched from Microsoft GW BASIC to Microsoft QuickBASIC around this time on the Olivetti M24. This did away with the need for line numbers and introduced named locations you could GOTO or GOSUB from.

    This inspired me to add a QB preprocessor to the PET 2001 emulator (https://masswerk.at/pet/).

    Since I don't want to be greedy or overly partial to the PET, here is, for all friends of other system, a tiny stand-alone QBASIC-to-BASIC transformer (should be agnostic of any dialects):

    https://masswerk.at/pet/qb-transform/

    • faassen 342 days ago
      Neat stuff!

      I your PET emulator and tried it in Firefox but had trouble (the keyboard buttons didn't seem to work, just in case that's news to you.

      • masswerk 342 days ago
        Hum, I'm actually developing und testing this Firefox first. – Maybe a case of bit gremlins in the wire? (Try a force reload: CTRL/Command+SHIFT+R.)

        Also mind that there are certain differences, when using "Edit mode" and "Games mode". (E.g., in edit mode, the shift keys are sticky, in games mode not.) Moreover, in games mode, the CAPS LOCK key of your physical keyboard acts as a toggle for virtual joystick and numeric key block mappings.

        • faassen 341 days ago
          That's mysterious, as it doesn't work on Firefox at for me. In Chrome after it says "READY" I can use the keyboard below it to things.

          On Firefox I get the "READY" but am then unable to use the keyboard or the drop-downs. When I click on a drop-down and wait for half a minute it might finally show it, but it's unusable. Firefox also regularly comes up with a warning that the page is slowing down Firefox, and the browser indeed seems to be hogging a single core.

          This is in Firefox 126.0 on Fedora 39.

          [update: I tried with safe-mode to disable any extensions but this doesn't make a difference]

          • masswerk 341 days ago
            Hum, this sounds like some kind of memory pressure.

            (This is hard to overcome: the emulator has to render in a 60Hz duty cycle and we're emulating a CPU at 1 Mhz. If sound is enabled, we also have to sample sound at 1 MHz, and resample this to 48KHz digital audio.)

            There seems to be some serious misconfiguration at play, though. For me, this runs on the oldest modern machine, I have around, a 2008 MacPro with the original ATI 256MB graphics card, under Firefox 78.15.0esr quite perfectly. This is probably puny in comparison to your setup.

            I guess, inadequate hardware acceleration may cause similar symptoms. I've seen this in the past (and in different context) with Chrome on older machines, where the frame rate drops to something like 2 or 4 fps, while it keeps up perfectly with hardware acceleration disabled. May be worth a try, maybe FF and your GPU driver do not play well together. Compare: https://support.mozilla.org/en-US/kb/performance-settings

  • More
lists | rss | source
Search:
Two Stop Bits is a discussion web site about retro computing and gaming.