Computer Old Farts Forum
 help / color / mirror / Atom feed
* [COFF] Butler Lampson's 1973 Xerox PARC memo "Why Alto?"
@ 2023-07-08  7:45 steve jenkin
  2023-07-09 21:03 ` [COFF] " Clem Cole
  0 siblings, 1 reply; 4+ messages in thread
From: steve jenkin @ 2023-07-08  7:45 UTC (permalink / raw)
  To: COFF

What struck me reading this is the estimated price (~$10K) to build an Alto, elsewhere I’ve seen $12K and 80 built in the first run.
 [ a note elsewhere says $4,000 on 128KB of RAM. 4k-bit or 16-kbit chips? unsure ]

I believe the first "PDP-11” bought by 127 at Bell Labs was ~$65k fully configured (Doug M could confirm or not), although the disk drive took some time to come.
Later, that model was called PDP-11/20.

Why the price difference?

PARC was doing DIY - it’s parts only, not a commercial production run with wages, space, tooling & R+D costs and marketing/sales to be amortised,
with a 80%+ Gross Margin  required, as per DEC.

Why didn’t Bell Labs build their own “Personal Computer” like PARC?
They had the need, the vision, the knowledge & expertise.

I’d suggest three reasons:

	- The Consent Decree. AT&T couldn’t get into the Computer Market, only able to build computers for internal use.
		They didn’t need GUI PC’s to run telephone exchanges.

	- Bell Labs management:
		they’d been burned by MULTICS and, rightly, refused the CSRC a PDP-10 in 1969.

	- Nobody ’needed’ to save money building another DIY low-performance device.
		A home-grown supercomputer maybe :)


It’s an accident of history that PARC could’ve, but didn’t, port Unix to the Alto in 1974.
By V7 in 1978, my guess it was too late because both sides had locked in ‘commercial’ positions and for PARC to rewrite code wasn’t justified: “If it ain’t Broke”… 

Porting Unix before 1974 was possible:
	PARC are sure to have had close contact with UC Berkeley and the hardware/software groups there.

Then 10 years later both Apple and Microsoft re-invent Graphical computing using commodity VLSI cpu’s.

Which was exactly the technology innovation path planned by Alan Kay in 1970:

	build today what’ll be cheap hardware in 10 years and figure out how to use it.

Ironic that in 1994 there was the big Apple v Microsoft  lawsuit over GUI’s & who owned what I.P.
Xerox woke up up midway through and filed their own infringement suit, and lost.
 [ dismissed because approx they'd waited too long ]

	<https://en.wikipedia.org/wiki/Apple_Computer,_Inc._v._Microsoft_Corp.>

==============

PDF:
	<http://bwl-website.s3-website.us-east-2.amazonaws.com/38a-WhyAlto/Acrobat.pdf>

Other formats:
	<http://bwl-website.s3-website.us-east-2.amazonaws.com/38a-WhyAlto/Abstract.html>

==============

--
Steve Jenkin, IT Systems and Design 
0412 786 915 (+61 412 786 915)
PO Box 38, Kippax ACT 2615, AUSTRALIA

mailto:sjenkin@canb.auug.org.au http://members.tip.net.au/~sjenkin


^ permalink raw reply	[flat|nested] 4+ messages in thread
* [COFF] Re: Butler Lampson's 1973 Xerox PARC memo "Why Alto?"
@ 2023-07-09 19:50 Noel Chiappa
  0 siblings, 0 replies; 4+ messages in thread
From: Noel Chiappa @ 2023-07-09 19:50 UTC (permalink / raw)
  To: coff; +Cc: jnc

    > From: steve jenkin

    > What struck me reading this is the estimated price (~$10K) to build an
    > .. [ a note elsewhere says $4,000 on 128KB of RAM. 4k-bit or 16-kbit
    > chips? unsure ]

16K (4116) - at least, in the Alto II I have images of. Maxc used 1103's
(1K), but they were a few years before the Alto.


    > I believe the first "PDP-11" bought by 127 at Bell Labs was ~$65k fully
    > configured

I got out my August 1971 -11/20 price sheet, and that sounds about right. The
machine had "24K bytes of core memory .. and a disk with 1K blocks (512K
bytes ... a single .5 MB disk .. every few hours' work by the typists meant
pushing out more information onto DECtape, because of the very small disk."
("The Evolution of the Unix Time-sharing System"):

 11,450	Basic machine CPU + 8KB memory
  6,000	16KB memory (maybe 7,000, if MM11-F)
  4,000	TC11 DECtape controller
  4,700	TU56 DECtape transport
  5,000	RF11 controller
  9,000	RS11 drive
  3,900	PC11 paper tape
-------
 44,050

(Although Bell probably got a discount?)

The machine later had an RK03:

  https://minnie.tuhs.org/cgi-bin/utree.pl?file=V1/u0.s

but that wasn't there initially (they are 2.4MB, larger than the stated
disk); it cost 5,900 (RK11 controller) + 9,000 (RK03 drive).

Also, no signs of the KE11-A in the V1 code (1,900 when it eventually
appeared). The machine had extra serial lines (on DC11's), but they weren't
much; 750 per line.

    > Why the price difference?

Memory was part of it. The -11/20 used core; $9,000 for the memory alone.

Also, the machine was a generation older, the first DEC machine built out of
IC's - all SSI. (It wasn't micro-coded; rather, a state machine. Cheap PROM
and SRAM didn't exist yet.)

	Noel

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2023-07-09 21:52 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-07-08  7:45 [COFF] Butler Lampson's 1973 Xerox PARC memo "Why Alto?" steve jenkin
2023-07-09 21:03 ` [COFF] " Clem Cole
2023-07-09 21:51   ` Larry Stewart
2023-07-09 19:50 Noel Chiappa

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).