25 Oct
2010
25 Oct
'10
6:46 p.m.
From: Mr Ian Primus <ian_primus at yahoo.com>
And glaringly so. To say that the 11/780 is the first
32 bit machine is just silly. Prime had a 32 bit machine in 1972. And I know that there
were others - but the Prime is the machine that I know the best :)
I think I'm right saying the Manchester 'Baby' had a 32 bit word in 1948,
actually 32 of them on one Williams tube. However as it was a serial machine the data path
to memory was actually one bit wide so it depends how you define bit size, but I was
taught it was the largest addressable unit of memory and by that definition it had a 32
bit word.
There was talk of the VAX design being the inspiration for the Motorola 68k. Isn't it
more likely that the PDP11 influenced the design of both the VAX and the 68k?
Actually as I worked for a defence contractor I knew about the 68k before I heard of the
VAX. The engineers did not believe the Motorola design was practical and we worried about
a large 64 pin chip in the environment of a military helicopter's avionics bay (G
forces, vibration, expansion, cooling etc) and it was decided to go with the 48pin Zilog
Z8001 instead. Possibly a big mistake but at the time sample Z8001s were available to us
but MC68000s were still estimated to be at best months away. When I left the company a
couple of years later we had just placed an order for a VAX 11/780 to augment our GEC
4080, GEC 4070 and a Prime.
25 Oct
25 Oct
6:56 p.m.
There was talk of the VAX design being the inspiration
for the Motorola 68k. Isn't it more likely that the PDP11 influenced the design of
both the VAX and the 68k?
Big microcoded CISC was the dominant thinking in computer architecture
at the time, so it is really hard to say that X influenced Y.
The engineers did not believe the Motorola design was
practical and we worried about a large 64 pin chip in the environment of a military
helicopter's avionics bay (G forces, vibration, expansion, cooling etc) and it was
decided to go with the 48pin Zilog Z8001 instead.
Why not use PGA or Flatpack?
--
Will
7:56 p.m.
On 25 Oct 2010 at 18:56, William Donzelli wrote:
The biggest problem at the time was supply and availability. We got
dog-and-pony shows from Intel, National, Zilog and Motorola. We
really liked Motorola, but, like National, delivery of actual silicon
(as well as production quantities) was "Real Soon Now". In fact, as
it I recall, it took National almost 3 years after their initial
presentation before they had production silicon ready for sale. The
big reason that the x86 got its popularity was because Intel was
substantially ahead of the crowd in availability.
Wasn't TI making some inroads with its I2L SPB9900 chips? I never
could get a sample from the TI sales rep.
How long did the Fairchild 9440 persist in military gear?
--Chuck
The engineers
did not believe the Motorola design was practical and
we worried about a large 64 pin chip in the environment of a
military helicopter's avionics bay (G forces, vibration, expansion,
cooling etc) and it was decided to go with the 48pin Zilog Z8001
instead.
Why not use PGA or Flatpack?
2:52 p.m.
On 26 Oct 2010 at 10:52, Eric Smith wrote:
Will wrote:
Well, maybe not from US manufacturers, but consider the NEC uPD768.
64-pin ceramic flatpack, 1978.
The quad flat package itself dates from at least the late 1960s.
See, for example, the Motorola XC177 in case 618, a 32-lead quad
ceramic package.
ISTR that the Japanese at the time were somewhat ahead of the US in
terms of high-density packaging. Didn't they originate the 64-pin
0.050" spaced DIP? I certainly recall seeing the fine-pitch DIP on a
lot of Japanese equipment.
I suspect that IBM and other mainframe manufacturers had some
proprietary high-density packaging at that time as well.
Bottom line is that in 1978 there were other alternatives to the 64-
pin 0.100" spaced giant DIP.
--Chuck
Why not use PGA or Flatpack?
Because
64-pin PGAs and flatpacks didn't exist in 1978. Even the
64-pin DIP was still fairly new. 
3:02 p.m.
On 10/26/2010 11:52 AM, Chuck Guzis wrote:
ISTR that the Japanese at the time were somewhat ahead
of the US in
terms of high-density packaging. Didn't they originate the 64-pin
0.050" spaced DIP?
I haven't seen a 0.050 inch pitch DIP. Perhaps
you're referring to the
0.070 inch pitch "Shrink-DIP", which was very common for a while from
Japanese vendors.
Rockwell and Motorola used a 0.050 inch pitch QUIP (each row on 0.100
inch pitch), Rockwell for 6500-series microcontrollers and related
parts, and Motorola for the MC10800 series ECL bit-slice components. I
don't recall exactly when the MC10800 series was introduced; perhaps
that actually could have been used for the MC68000 had Motorola wished
to do so. (Note that Intel, Zilog, and AMP used the term "QUIP" for an
entirely different ceramic leadless package.)
The JEDEC 68-position ceramic leadless chip carriers appeared around
1981, and Motorola offered the MC68000 in that package. The PLCC
appeared a few years later.
4:53 p.m.
On 26 Oct 2010 at 12:02, Eric Smith wrote:
I haven't seen a 0.050 inch pitch DIP. Perhaps
you're referring to
the 0.070 inch pitch "Shrink-DIP", which was very common for a while
from Japanese vendors.
Yes, my error--e.g. HD64180-style package. I remember seeing the
same package in Japanese 70's era telephone answering machines.
The JEDEC 68-position ceramic leadless chip carriers
appeared around
1981, and Motorola offered the MC68000 in that package. The PLCC
appeared a few years later.
The ceramic LCC was at least known by 1981--we got early steppings of
the 186 and 286 in that configuration. With the 68K it was pretty
close in terms of timeframe.
--Chuck
5:32 p.m.
Anent chp packaging...
In my hellbox, I've got a couple of Fujitsu MB8869 chips--I think
they're CRT controllers, (but that's just a guess; I've never seen a
datasheet). They date from around 1980 or earlier.
They're 64-pin PGA packages--ceramic with a metal "hood". Pins are
on 0.100" centers.
Not mounted in ZIF sockets, but rather just a conventional friction-
fit socket.
--Chuck
11:51 p.m.
I haven't seen a 0.050 inch pitch DIP. ?Perhaps
you're referring to the
0.070 inch pitch "Shrink-DIP", which was very common for a while from
Japanese vendors.
I remember seeing them. At one point I had a calculator that had the
Shrink DIP (0.070 inch) and and even finer pitch DIP (assume it was
0.050 inch). Oddly, they were both surface mounted gull wing style.
--
Will
11:46 p.m.
Because 64-pin PGAs and flatpacks didn't exist in
1978. ?Even the 64-pin DIP
was still fairly new.
I am pretty sure big flatpacks were available for hybrids back then.
Maybe Motorola did not offer it in the databook, but for a big enough
government contract, they would have stuffed the dies in the packs
(even third party).
--
Will
27 Oct
27 Oct
9:53 a.m.
New subject: Chip Packaging (was Happy Birthday VAX)
Mitsubishi had some large-scale(for the time) ICs packaged as flatpack
ceramic packages with 48 pins at a pitch smaller than 0.1" back in
1970/1971 timeframe. The chipset was used in calculators, specifically
the Denon DEC-311 (an unusual calculator that didn't support division),
as the MA8011/8012/8013. The socketing for the chips was quite
unusual.
As mentioned by an earlier poster, the Japanese did seem to have an
advantage in higher-density packaging over the US and others for a
period of time in the 1970's.
http://oldcalculatormuseum.com/denon311.html
Earlier yet, in 1965-ish timeframe, General Micro-Electronics built a
large-scale chipset for Victor's 3900 calculator that utilized round
ceramic flat-pack devices with 22 leads. Not quite at the level of a
68000 in terms of pincount, but still pretty amazing for the time.
Getting the packaging right was a huge undertaking at that time.
http://pail.bensene.com/d-victor3900.html (a draft, not yet completed).
Rick Bensene
The Old Calculator Museum
http://oldcalculatormuseum.com
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