• JHamby (unregistered) in reply to AlpineR
    AlpineR:
    I got a Commodore 128 around 1986 and it featured triple booting: C64, C128, and CP/M. C64 mode was essential for running video games and C128 mode had a much nicer dialect of BASIC. I thought that CP/M mode must be useful for something, but all it seemed to do was "store files, load code into memory, and run code in memory". Considering that there were no programs included and that I never found any software online, I really wonder what the designers thought was so great about including CP/M.

    I got a C128 around "earlier this week" (gotta love eBay, yes I'm a retrocomputing nerd), and yes, the CP/M mode is pretty worthless. According to Bil Herd, one of the lead designers:

    http://www.ffd2.com/fridge/chacking/c=hacking17.txt

    About the Z80:

    What court ordered Commodore to install the Z80?

    It wasn't mandated by court order, it was mandated by a 23 year old engineer that realized that marketing had gone and said that we were 100% compatible. This turned out to be a hard nut to crack as no-one knew what C64 compatibility meant. Companies who designed cartridges for the C64 used glitches to clock their circuitry not realizing that the glitches were not to be depended on, etc.

    The Z80/CPM cartridge didn't work on all C64's, and no-one had really taken the time to figure out why. Someone noticed that a certain brand of the address buffer used in the CPM cart worked better than others so someone concluded that it must be the timing parameters that made a difference. This wasn't true, it was a very subtle problem that dealt with the way the 6502, the Z80 and the DRAM had been interlaced together. So here we had a CPM cart that didn't work with all C64's and it worked even less reliably with the C128 even though the timing parameters in the C128 were far better. In my opinion you couldn't call the C128 compatible with the CPM cart as it only ran 20% of the time when tested overnight.

    ALSO, I worked hard to make sure the C128 had a reliable power supply. I was told "no fuse'..... oops one got in there by accident... in fact it was easily accessible... darn it anyway. However, with the wide variations in minimum and maximum power supply requirements we couldn't handle the CPM cart, it needed an additional .5 amp because of some wasteful power techniques that were used in it. I couldn't foot the bill for an additional .5 amp that might only occasionally be used.

    SO, with that said, I accidentally designed the Z80 into the next rev of the board. We designed the C128 in 6 months from start to finish INCLUDING custom silicon, these were records back then, the Z80 was added around the second month.

    I also remember reading that the Z80 is an integral part of the startup logic for the C128, so you can't have one without it. Fortunately, VICE emulates the Z80 and you can run C128 CP/M with the .D64 images. Again, why you'd want to is another issue. My goal is to find a way to copy Zork I-III and a few other amusing looking programs from http://www.retroarchive.org/cpm/ to a C128 CP/M floppy and then call it a day.

  • Eternal Density (unregistered) in reply to PSWorx
    PSWorx:
    until i realized that the program actually ran as expected, just that iterating through every single possible path on an almost blank 100x100 cells grid might *just maybe* not be the best idea...
    I discovered the same thing, except I was using such an algorithm for drawing a 3d maze in OpenGL, which consisted of cubes, each of which connected to up to 6 other cubes. While it only draws out to a certain distance, and will never visit a cube that is closer to the origin that one one it last drew (to prevent drawing unnecessary things, and/or in an infinite loop), it only works for single-cube corridors. As soon as a bunch of cubes are interconnected, there are a huge number multiple paths forward, as you discovered. Except it's worse for 3d, and when you are rendering faces of a cube each time, as opposed to just searching...
  • (cs) in reply to snoofle
    snoofle:
    Philippe:
    It wasn't a recursion problem. As others have noted, it was more of a scaling problem - the amount of disk space required to store the log data was quickly exhausted.

    This is a WTF along the lines of "no one will ever need more than 640K of RAM" and "14MB of disk space is such a huge amount of disk that no conceivable process could ever fill it up."

    You youngsters and your terabyte filesystems and gigahertz processors...

    I have twin 114GB drives on a 3 year old system (not too shabby for it's day). Even with a few thousand photos of the kids, hundreds of songs and a handful of movies, I've only used about 30GB, and most of that is Windows updates.

    Just curious: what do people put on these huge disks to fill them up (I mean besides porn)? And how much of it is actually useful?

    most people? P I R A C Y

    Personally, mine's full of games. These days most games come on DVD and install about 4gb of data. When you never uninstall any of them, your games folder can easily grow to 100gb...

  • Wi (unregistered) in reply to Anonymous
    Anonymous:
    Dark Shikari:
    puzzled:
    Why would you want to download wikipedia that justs sounds crazy...

    Well its only a few gigabytes 7zipped. Heck you can get the entire full-pages history, probably over a terabyte uncompressed, in just an 8.5GB 7zip file. They're available for download on the database dump page.

    They're in XML format, so you have to parse it first though. And yes, its one giant XML file. 0.o

    Can anyone explain why they would only offer their database dump in XML? It seems like that's one of the least efficient ways of doing it.

    They offer you the pages to download: http://static.wikipedia.org/ (uncompressing to a bunch of files)

  • Roberto Iza Valdez (unregistered)

    What a treat!

  • Simmo (unregistered) in reply to Saladin
    Saladin:
    phaedrus:
    Have you seen any recent video games? The install size for Quake4 was over 2GB. Ten games could mean anywhere from 20 to 50GB of disk space.
    Off the top of my head, full installs for a few games:

    Neverwinter Nights 2: ~7.5GB TES4 Oblivion: ~6GB Unreal Tournament 2004: ~4.5GB (perhaps after a mappack or two) Diablo II with expansion (keep in mind that this game is about seven years old): ~4GB I believe

    It adds up really fast X_x

    I have a mate working on a PS3 game coming out later this year. It will occupy almost all of a Blu-Ray disk. Dunno how big they are but must be close to 50Gb?

    [btw Alex these captchas (darwin) are a little too obvious I reckon]

  • (cs) in reply to TheRealBill
    TheRealBill:
    pistole:
    ahh CP/M ..

    I learned programming basic (and assembly) on a Z80 running CP/m (mind you: an Exidy Sorcerer, for those old and grey enough to remember) back in the 80's. Brings back good memories :)

    "grey enough" implies we still have hair.

    My very first computer was an Exidy Sorcerer. I was 15 or so at the time and my father bought one to play with it. So, actually, the computer wasn't technically mine, but of course I spent more time with it than my dad. This box was THE thing that got me into the programming business. Today I'm bald (not grey...)

    A very interesting part about that computer was the printer my dad bought for it. Can't remember the make or name of it, but it was a regular typewriter (with an exchangeable "wheel" with the letters on it, so different fonts could be printed). The computer interface was a special PCB sporting a Centronics cable at one end and with a wire soldered to each keyboard key.

  • Yorch (unregistered) in reply to snoofle

    Please tell me you read the story and you're not a user lost in a page he doesn't understand....

  • Jeff (unregistered) in reply to bramster

    CP/M on the Amstrad CPC6128 used 3" floppies (not 3.5"!). The editor and assembler I used on that were pretty good at the time (ed80 and gen80 I think). Used them to write some Amstrad and ZX Spectrum games at the time.

  • Delenit (unregistered) in reply to RON

    Or simply Dijkstra's algorithm?

  • eric bloedow (unregistered)

    this story reminds me of one i read somewhere...i forget the details, but basically management forced everyone to use a "windows emulator" program, running on the SAME version of windows! everyone hated it, but management flatly refused to listen to their complaints...

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