Very interesting Thomas, thanks for sharing.
You can of course program an Alpha using VAX Macro-32, as a compiled language, if that is
your kind of thing.
Regards, Mark
From: owner-hecnet at Update.UU.SE <owner-hecnet at Update.UU.SE> On Behalf Of
Thomas DeBellis
Sent: 22 April 2020 23:59
To: hecnet at Update.UU.SE
Subject: Re: [HECnet] Apparently good news from VSI
Why, indeed. I think after you've programmed enough assembler, you find things to
like and detest about all of them. So I've done BAL-360, PDP-10, PDP-11, PDP-8, Intel
80286 and up as well as VAX and Alpha. There were others. Which one did I like most?
Why, the ones I got paid to work on, of course.
After that, what mattered was how friendly the development environment was and in that
regard, the 360 really drove me crazy; very poor non-interactive debugging tools (at the
time). The PDP-10's debugger was wonderful as well as the instruction set and a
reasonable amount of registers. The PDP-8 mimicked that to a certain extent, so the fact
that there is only one accumulator presented an interesting challenge. Ditto my
experience with the 11. I honestly don't remember enough VAX assembler to comment
meaningfully on it.
Passing to the Intel chips, I would really say it mattered what development tools you
used. Microsoft's show the Macro-10 heritage and the Codeview debugger was completely
reasonable. There were a number of things that bothered me, but the register file
wasn't one of them; not after the PDP-8. The segmented memory model never bothered me
at all; not when it offered half a gigabyte of virtual address space on the 286 (2**13
selectors * 64K). As a matter of fact, I thought it was great because it gave more
granularity than guard pages, which is all you can use on the VAX, Alpha and PDP-10.
But really, only a real nerd (like me) would care about any of this. Otherwise, you
really can't tell; not in most high level languages. And I think Linus probably said
it best when he noted that the Intel chips were so fast that register scheduling really
didn't matter. It's true, particularly because behind the curtain it's doing
register score-boarding.
You might want to check out AMD's 64 bit extensions to the 80x86 ISA; I've taught
that assembler and it's quite reasonable, particularly if you are not using the arcane
AT&T syntax: 16 registers and more flexibility in using them; very close to the VAX
and PDP-10. I miss PushA, though. Or maybe I like x86-64 because I got paid to use it.
Really, Paul; this is a matter of personal taste more than anything else--I don't
think it's possible to decide anything more than what you like...
_____
On 4/22/20 9:44 AM, Paul Koning wrote:
I can see an Alpha, but why would you want a wacko architecture created by Intel?
It's not as if they have any track record of designing nice CPU architectures.
paul
_____
On Apr 22, 2020, at 9:30 AM, Keith Halewood <mailto:Keith.Halewood at
pitbulluk.org> <Keith.Halewood at pitbulluk.org> wrote:
I might actually go out and buy a cheap alpha or itanic at some point now?.. if such
things exist.