Re: PDP-8 ASCII question

From	Morten Reistad <first@last.name.invalid>
Newsgroups	comp.sys.prime
Subject	Re: PDP-8 ASCII question
Date	2016-04-05 16:05 +0200
Organization	Me, Myself and I
Message-ID	<9atctc-4ec.ln1@sambook.reistad.name> (permalink)
References	<7ac59376-b031-44ac-9601-490ec29b3ece@googlegroups.com> <3cSdnc2MWvG_jZ7KnZ2dnUU7-VfNnZ2d@giganews.com> <m4ibtc-eca.ln1@sambook.reistad.name> <58a75f84-abea-4d96-a79d-9ec639f6fc26@googlegroups.com>

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In article <58a75f84-abea-4d96-a79d-9ec639f6fc26@googlegroups.com>,
Jim Wilcoxson  <prirun@gmail.com> wrote:
>On Monday, April 4, 2016 at 10:18:33 PM UTC-4, Morten Reistad wrote:
>> In article <3cSdnc2MWvG_jZ7KnZ2dnUU7-VfNnZ2d@giganews.com>,
>> Dennis Boone <drb@ihatespam.msu.edu> wrote:
>> > > ISTR that the earliest Primes (up to the 400, ISTR) were embrace-and-extend
>> > > versions of the DDP-5xx architecture. Later versions had compatibility-mode
>> > > (R-mode?) that ran DDP-516 code. 
>> >
>> >Prime called the x16 mode S mode.  As far as I know, it existed
>> >until the end.  Even the 100 and 200 had R-mode, though, the "embrace
>> >and extend".
>> >
>> >The P300 added virtual memory.
>> 
>> They sure had a lot of processor modes, S, R, I, V and IX. This puts even
>> a '486 and an ARM8 (with 64, 32 and 24 bit modes plus thumb2) to shame.
>> 
>> -- mrr
>
>And within each processor mode are multiple addressing schemes indicated in a different way in each mode:
>
>- sector 0 relative
>- program counter relative
>- preindexed by index register
>- postindexed by index register
>- optional indirect
>- base register relative (4 varieties)
>- field address register relative
>- general register relative
>- gr indexed

I discovered this in october 1984 when I read the processor and PMA
manuals for Primos 19.3; while upgrading to 19.4.

That was when I decided that I'll stick to procedural languages, after
doing assembly programming for nearly a decade. First the 6502, then the
PDP10, then the Z80, a little PDP11s, and then the Prime. After a few
weeks with PMA I went for FTN, PLP, SPL and all the other Prime-specific
stuff. 

-- mrr

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Re: PDP-8 ASCII question Morten Reistad <first@last.name.invalid> - 2016-04-04 16:15 +0200
  Re: PDP-8 ASCII question Bob Eager <news0006@eager.cx> - 2016-04-04 18:23 +0000
  Re: PDP-8 ASCII question drb@ihatespam.msu.edu (Dennis Boone) - 2016-04-04 20:08 -0500
    Re: PDP-8 ASCII question Morten Reistad <first@last.name.invalid> - 2016-04-05 03:48 +0200
      Re: PDP-8 ASCII question Jim Wilcoxson <prirun@gmail.com> - 2016-04-05 06:27 -0700
        Re: PDP-8 ASCII question Morten Reistad <first@last.name.invalid> - 2016-04-05 16:05 +0200
          Re: PDP-8 ASCII question Greg Field <greg.field.au@gmail.com> - 2018-11-04 18:26 -0800
            Re: PDP-8 ASCII question Jim Wilcoxson <prirun@gmail.com> - 2018-11-05 07:15 -0800

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