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Previously on "6802 with OS/9 Contract"

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  • Churchill
    replied
    Originally posted by RichardCranium View Post
    Hijacking this thread again...

    I worked on an Apple Lisa for a while.

    It was staggeringly exciting machine. I went to it from MP/M and was awe-struck with the leap in the interface.

    I was a gorgeous machine to use and a delight to do development work on it. I haven't a clue what it was we were developing, but it never sold.

    When I first used a computer (some form of Altair) I had an epiphany: I suddenly knew what I wanted to do with the rest of my life.

    But the feeling I had when I saw the Lisa completely overwhelmed that. I couldn't believe such an immense leap from the command line to the intuitive Lisa interface was possible. It was, without doubt, the way the world was headed.





    This was "Richard Cranium's Tulipe Conclusions". Number 7 in a series of 136.
    From a development point of view it was a major transition from a "Just do it" to a "Please do it" methodology.

    Oh those halcyon days...
    (Whadya mean I've got to post a message...?)

    Leave a comment:


  • Platypus
    replied
    Originally posted by RichardCranium View Post
    It's trivial, but it's bugging me.

    Can I just say ...

    ... Apple ][

    ?
    Yes you may. Well remembered !

    Leave a comment:


  • RichardCranium
    replied
    Hijacking this thread again...

    I worked on an Apple Lisa for a while.

    It was staggeringly exciting machine. I went to it from MP/M and was awe-struck with the leap in the interface.

    I was a gorgeous machine to use and a delight to do development work on it. I haven't a clue what it was we were developing, but it never sold.

    When I first used a computer (some form of Altair) I had an epiphany: I suddenly knew what I wanted to do with the rest of my life.

    But the feeling I had when I saw the Lisa completely overwhelmed that. I couldn't believe such an immense leap from the command line to the intuitive Lisa interface was possible. It was, without doubt, the way the world was headed.





    This was "Richard Cranium's Tulipe Conclusions". Number 7 in a series of 136.

    Leave a comment:


  • RichardCranium
    replied
    It's trivial, but it's bugging me.

    Can I just say ...

    ... Apple ][

    ?

    Leave a comment:


  • Churchill
    replied
    Originally posted by NickFitz View Post
    I used to muck about with ARM assembler about fifteen years ago on an Acorn A3000 - writing sprite routines and so on.

    I should have stuck with it
    I did.

    I loved the Archimedes', lovely machines.

    Have a gander at... Castle Technology...

    Leave a comment:


  • NickFitz
    replied
    Originally posted by Churchill View Post
    The've always been fashionable. You just forgot where to look.

    With regards to the RISC vs CISC debate, just look at the money ARM has made...
    I used to muck about with ARM assembler about fifteen years ago on an Acorn A3000 - writing sprite routines and so on.

    I should have stuck with it

    Leave a comment:


  • NickFitz
    replied
    Originally posted by VectraMan View Post
    I assume you mean "LOOP", but I didn't think that was in z80. I can't say I've ever used it in x86 either, nothing wrong with dec and a jump not zero.
    DJNZ label

    Nothing wrong with
    Code:
    DEX
    BNE label
    IM(&Y)HO

    Leave a comment:


  • Churchill
    replied
    Originally posted by VectraMan View Post
    I programmed 6502 on an Oric-1, and then Z80 on a Tatung Einstein.



    I assume you mean "LOOP", but I didn't think that was in z80. I can't say I've ever used it in x86 either, nothing wrong with dec and a jump not zero.

    I went to an Intel developer conference once where they told us to only use the "RISC" instruction as they were much more optimised, and the more sophisticated CISC instructions were only included for backwards compatibility. And implementing a complex instruction yourself with the RISC instructions was much better, even if it meant 10 instructions instead of one.

    I guess to some extent Intel were victims of their own success: they couldn't release something clean and simple because they had to make the chips backwards compatible.

    I wonder if assembler skills will ever become fashionable again.
    The've always been fashionable. You just forgot where to look.

    With regards to the RISC vs CISC debate, just look at the money ARM has made...

    Leave a comment:


  • VectraMan
    replied
    I programmed 6502 on an Oric-1, and then Z80 on a Tatung Einstein.

    Originally posted by NickFitz View Post
    Having an instruction that meant they didn't have to keep track of the loop index themselves was more important to the Zilog enthusiasts.
    I assume you mean "LOOP", but I didn't think that was in z80. I can't say I've ever used it in x86 either, nothing wrong with dec and a jump not zero.

    I went to an Intel developer conference once where they told us to only use the "RISC" instruction as they were much more optimised, and the more sophisticated CISC instructions were only included for backwards compatibility. And implementing a complex instruction yourself with the RISC instructions was much better, even if it meant 10 instructions instead of one.

    I guess to some extent Intel were victims of their own success: they couldn't release something clean and simple because they had to make the chips backwards compatible.

    I wonder if assembler skills will ever become fashionable again.

    Leave a comment:


  • Diver
    replied
    I deny all responsibility for hijacking this thread

    Leave a comment:


  • Churchill
    replied
    Originally posted by NickFitz View Post
    DOH!

    Of course it did, it was the original Trash 80s that use the Z80
    Well bugger me! I've out-geeked a geek!

    The Z80(x) chips were quite famous for their ability to run CP/M apps so I don't think the TRS/80 was that crap.

    In fact there used to be a TRS80 Business Center on Deansgate in Manchester.

    Leave a comment:


  • NickFitz
    replied
    Originally posted by Churchill View Post
    Wrong, wrong, wrong.

    The Tandy Color(sic) Computer utilised a 6809 derivative.

    DOH!

    Of course it did, it was the original Trash 80s that use the Z80

    Leave a comment:


  • Churchill
    replied
    Originally posted by NickFitz View Post
    No need to top yourself yet, Diver: the TRS80CC may have had a Zilog chip (as implied by the "80"), but it also ran OS/9 - so that's probably where you used that OS, although the instruction set used by the processor specified for this contract would be somewhat different
    Wrong, wrong, wrong.

    The Tandy Color(sic) Computer utilised a 6809 derivative.

    Leave a comment:


  • NickFitz
    replied
    Originally posted by Diver View Post
    No need to top yourself yet, Diver: the TRS80CC may have had a Zilog chip (as implied by the "80"), but it also ran OS/9 - so that's probably where you used that OS, although the instruction set used by the processor specified for this contract would be somewhat different

    Leave a comment:


  • NickFitz
    replied
    Originally posted by Platypus View Post
    I thought the Tandy was a Zilog Z80 processor?

    MAC boys no, but Apple II boys I think.

    I programmed 6502 on a Commodore Pet
    The Apple II (and, indeed, Apple I) had a 6502 processor (which was manufactured by MOS Technology, not Motorola). The original Mac had a 68000, which was from Motorola, and all Macs had 680x0 chips until the PowerPC range was introduced (although Mac OS could still run 680x0 code under automatic emulation right until OS X was introduced - indeed, a friend of mine only got rid of his last Mac OS 9.x machine a couple of years ago, when he'd found a suitable replacement for a font utility he'd been using from his 68030 Mac II onwards).

    The Apple III also had a 6502-family processor, although nobody really likes to talk about that one - in fact, when a batch of Apple IIIs were stolen from a warehouse at the time when they were still on sale, the local police chief described the thieves as "dumb"

    Z80 was for people who prized high-level processor instructions over computational efficiency. People who can't think down to the level of "these values are asserted on the low-order 8 bits of the address bus and the upper 8 bits of the address bus are ignored during the fetch of the operand... of course, that's why accessing values in page zero saves a clock cycle! "

    Having an instruction that meant they didn't have to keep track of the loop index themselves was more important to the Zilog enthusiasts.

    In my experience, many of them would crow about "their" processor running at 6 MHz, while 6502s in competing systems "only" ran at 2 Mhz... they didn't even realise that the microcoding of the Z80, compared to the hard-wiring of the 6502, meant that the Z80 had to run at 6 MHz to have the same speed as a 6502 running at 2 MHz - but this also meant that it consumed more power and ran hotter.

    There are good reasons why the 6502 was called "the first RISC processor". And there are good reasons why RISC processors didn't win out over CISC processors, the primary reason being that most people who dignify themselves with the term "programmer" are too ignorant of the way a von Neumann architecture processor works to be able to make any adequate use of it.

    The triumph of the Intel chip is a triumph of the dumb masses over the truly competent. Still, we're stuck with it now
    Last edited by NickFitz; 13 July 2008, 04:33.

    Leave a comment:

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