Re: DECSYSTEM 20

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Article #1710

#1710

From: Bill Pechter
Date: Mon, 31 Jul 1989 14:40

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In article <976@mplvax.EDU> cdl@mplvax.ucsd.edu.UUCP (Carl Lowenstein) writes:
>Some of the medium-early 11's (11/10 and 11/05 specifically)
>had a register set that was addressable on the bus by a program.
>Others of earlier and later vintage did not.
>

I believe every 11 had the registers addressable on the bus via a program...
Includeing the 11/70.  The trick was knowing the addressing space (memory
management).
a

>Of course, all *Real* PDP-11's can read and load their
>register set through the front panel lights and switches. 
>Nowadays, the lights and switches must cost more than
>the CPU chip, so they don't make them like that.


I remember and love the front panels -- especially the DecDatasystem 570
version of the 11/70 (or the unreleased 11/74 type where the 11/05 type short
switches were used.

Bill

-- 
Bill Pechter -- Home - 103 Governors Road, Lakewood, NJ 08701 (201)370-0709
Work -- Concurrent Computer Corp., 2 Crescent Pl, MS 172, Oceanport,NJ 07757 
Phone -- (201)870-4780    Usenet  . . .  rutgers!pedsga!tsdiag!scr1!pechter
  **   MS-DOS is CP/M on steroids, bigger bulkier and not much better  **

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<3256@wpi.wpi.edu> <EGDORF.89Jul21195924@zaphod.lanl.gov> <443@anasaz.UUCP> <BRUCE.89Jul23155646@heather.pooh.com> <3893@phri.UUCP> <433@scr1.UUCP> <976@mplvax.EDU>

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Path: arc1-ca.pugleaf.net!utzoo!attcan!utgpu!watmath!att!tsdiag!scr1!pechter
From: pechter@scr1.UUCP (Bill Pechter)
Newsgroups: comp.arch
Subject: Re: DECSYSTEM 20
Message-ID: <441@scr1.UUCP>
Date: 31 Jul 89 14:40:05 GMT
References: <3256@wpi.wpi.edu> <EGDORF.89Jul21195924@zaphod.lanl.gov> <443@anasaz.UUCP> <BRUCE.89Jul23155646@heather.pooh.com> <3893@phri.UUCP> <433@scr1.UUCP> <976@mplvax.EDU>
Reply-To: pechter@scr1.UUCP (Bill Pechter)
Organization: CONCURRENT COMPUTER,OCEANPORT NJ
Lines: 28
Summary: register address via Unibus

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