23 Apr
2016
23 Apr
'16
8:41 a.m.
From: Brent Hilpert
I'd say the 74181 (1970) deserves a mention here.
Simpler (no register
component, ALU only) but it pretty much kicked off the start of
IC-level bit slicing.
Yes, it was used in quite a few machines. Among the PDP-11's alone, it is
found in the -11/45, /05, /40, /04 and /34, to name a few that I checked
quickly, and almost certainly others too (e.g. /70).
Noel
23 Apr
23 Apr
11:38 a.m.
On 04/23/2016 07:41 AM, Noel Chiappa wrote:
The 11/45 and 11/70 are mostly the same processor.
Definitely, the data paths boards and FPU are the same part
numbers.
Jon
From: Brent
Hilpert
I'd say the 74181 (1970) deserves a mention
here. Simpler (no register
component, ALU only) but it pretty much kicked off the start of
IC-level bit slicing.
Yes, it was used in quite a few machines. Among the PDP-11's alone, it is
found in the -11/45, /05, /40, /04 and /34, to name a few that I checked
quickly, and almost certainly others too (e.g. /70).
1:06 p.m.
On 04/23/2016 05:41 AM, Noel Chiappa wrote:
I recall reading about the 74181 introduction back in the day--it
created great excitement and speculation about how far the industry was
From: Brent
Hilpert
> I'd say the 74181 (1970) deserves a mention here. Simpler (no
> register component, ALU only) but it pretty much kicked off the
> start of IC-level bit slicing. from a computer-on-a-chip. I think I still have a
couple of the things
in my hellbox.
In the day, I'm not certain that TTL had the edge on integration,
however. It always seemed that DTL and RTL had the edge in complexity.
Before the 181, I was playing around with the RTL 796 dual full adder
and an 8-bit Fairchild DTL memory--IIRC the latter used a 7V clock.
The interesting thing was that there seemed to be a distrust of LSI
chips early on. I recall working on a project around 1973, where the
lead engineer preferred to design his own UART from SSI rather than use
one of the new UART chips.
--Chuck
5:34 p.m.
On 2016-Apr-23, at 10:06 AM, Chuck Guzis wrote:
On 04/23/2016 05:41 AM, Noel Chiappa wrote:
I recall reading about the 74181 introduction back in the day--it
created great excitement and speculation about how far the industry was
from a computer-on-a-chip. I think I still have a couple of the things
in my hellbox.
In 1972 or 1973 one of Radio Electronics or Popular Electronics had a construction article
for the E&L Instruments Digi-Designer.
If you recall, the Digi-Designer was essentially a vehicle for E&L's new plug-in
breadboard. For those younger, yes, -those- plug-in breadboards, that are still the most
prevalent hardware prototyping/educational technique today.
AIR, the 74181 was featured as an experiment to wire up on the Digi-Designer in that
article.
From:
Brent Hilpert
> I'd say the 74181 (1970) deserves a mention here. Simpler (no
> register component, ALU only) but it pretty much kicked off the
> start of IC-level bit slicing. In the day, I'm not certain that TTL had the edge
on integration,
however. It always seemed that DTL and RTL had the edge in complexity.
Before the 181, I was playing around with the RTL 796 dual full adder
and an 8-bit Fairchild DTL memory--IIRC the latter used a 7V clock.
I think TTL was quickly on par for density with DTL & RTL and overtook them by the
late 60s.
I have 7490s (decade counter) from late-1966 and early-1967, and many TTL MSI functions
were there by 1969.
The 7484 (16-bit memory) is listed in the TI 1969 TTL databook.
RTL was passe by then and DTL was heading that way. I don't think DTL got any more
complex than such as the 8-bit memory you mention, at least in the main.
I was surprised by the early date code on the 7490s when I ran across them in a piece of
test equipment.
The interesting thing was that there seemed to be a
distrust of LSI
chips early on. I recall working on a project around 1973, where the
lead engineer preferred to design his own UART from SSI rather than use
one of the new UART chips.
--Chuck
6:46 p.m.
On 04/23/2016 02:34 PM, Brent Hilpert wrote:
I was surprised by the early date code on the 7490s
when I ran across
them in a piece of test equipment.
What was surprising to me is how quickly the industry standardized on
the TI 7400/5400 parts. Early (ca 1967) Moto databooks had MTTL I,
MTTL II and MTTL III that were essentially sui generis. By 1969, the
MC7400/5400 had pretty much taken over. Things moved really quickly
back then.
I recall the mW MRTL "experimenter's pack" with HEP part numbers. IIRC,
about half the projects in the accompanying booklet used the RTL stuff
in analog, not digital applications.
--Chuck
7:15 p.m.
On 04/23/2016 05:46 PM, Chuck Guzis wrote:
On 04/23/2016 02:34 PM, Brent Hilpert wrote:
Lots of designers and system manufacturers were VERY leery
of adopting anything single-source.
When a number of chip makers (Nat Semi, Motorola, Signetics,
Fairchild) all jumped onto making compatible 7400 parts, the
industry had the confidence that parts in the series would
be available for a long time. Back in the late 60's, early
70's the industry was moving at a breakneck pace, and chip
families had very short lifetimes before their makers hopped
onto the next new thing. (Oh, yeah, you said the same thing
in the last sentence!)
Jon
I was surprised by the early date code on the
7490s when I ran across
them in a piece of test equipment.
What was surprising to me is how quickly the
industry standardized on
the TI 7400/5400 parts. Early (ca 1967) Moto databooks had MTTL I,
MTTL II and MTTL III that were essentially sui generis. By 1969, the
MC7400/5400 had pretty much taken over. Things moved really quickly
back then.
9:05 p.m.
On 2016-Apr-23, at 4:15 PM, Jon Elson wrote:
On 04/23/2016 05:46 PM, Chuck Guzis wrote:
Fellow here did some research into the 181 history and came to a similar conclusion:
http://ygg-it.tripod.com/id1.html
He suggests TI being the first to contract for a second-source sent the buyers (esp.
military) to the 7400 series.
On 04/23/2016 02:34 PM, Brent Hilpert wrote:
Lots of designers and system manufacturers were VERY leery of adopting anything
single-source.
When a number of chip makers (Nat Semi, Motorola, Signetics, Fairchild) all jumped onto
making compatible 7400 parts, the industry had the confidence that parts in the series
would be available for a long time. Back in the late 60's, early 70's the
industry was moving at a breakneck pace, and chip families had very short lifetimes before
their makers hopped onto the next new thing. (Oh, yeah, you said the same thing in the
last sentence!) I was surprised by the early date code on the
7490s when I ran across
them in a piece of test equipment.
What was surprising to me is how quickly the
industry standardized on
the TI 7400/5400 parts. Early (ca 1967) Moto databooks had MTTL I,
MTTL II and MTTL III that were essentially sui generis. By 1969, the
MC7400/5400 had pretty much taken over. Things moved really quickly
back then.
10:32 p.m.
I recall going to Mike Quinn's and seeing barrels of RTL.
I wish now that I'd bought a bunch of them.
Most DTL can be replace by a TTL except a few with different
pinouts and the NAND with the diode expand pin.
My oldest equipment has a mix of DTL and TTL.
Dwight
24 Apr
24 Apr
4:33 p.m.
On 4/23/2016 8:32 PM, dwight wrote:
I recall going to Mike Quinn's and seeing barrels
of RTL.
I wish now that I'd bought a bunch of them.
Most DTL can be replace by a TTL except a few with different
pinouts and the NAND with the diode expand pin.
My oldest equipment has a mix of DTL and TTL.
Dwight
All I ever saw was the ads like this.
https://www.flickr.com/photos/oskay/4455981283/
Ben
6:51 p.m.
On 04/24/2016 03:33 PM, ben wrote:
On 4/23/2016 8:32 PM, dwight wrote:
Wrong coast! Poly Paks was an East Coast outfit.
Mike Quinn's was at the Oakland, CA airport. I first saw it
in the early 1990's, I think, when it was still in the WW-II
temp building on the airport property. You were literally
walking on 3" of crunched circuit boards in the back rooms!
There were large tables covered with circuit boards and
small units, and the stuff that slid off the tables just
became the floor covering.
They had tons of boards out of computers and electronic
equipment. The best stuff was kept in front in glass cases
next to the cash register.
Jon
I recall going to Mike Quinn's and seeing
barrels of RTL.
I wish now that I'd bought a bunch of them.
Most DTL can be replace by a TTL except a few with different
pinouts and the NAND with the diode expand pin.
My oldest equipment has a mix of DTL and TTL.
Dwight
All I ever saw was the ads like this.
https://www.flickr.com/photos/oskay/4455981283/
25 Apr
25 Apr
6:51 p.m.
Ah PolyPaks!
The parts were always guaranteed. If they were bad,
you could send them back and then you could test the next
one.
They surely created the term "You-Test-Em".
Dwight
________________________________________
From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Jon Elson <elson at
pico-systems.com>
Sent: Sunday, April 24, 2016 3:51 PM
To: General at classiccmp.org; Discussion@
Subject: Re: bit slice chips (was Re: Harris H800 Computer)
On 04/24/2016 03:33 PM, ben wrote:
On 4/23/2016 8:32 PM, dwight wrote:
Wrong coast! Poly Paks was an East Coast outfit.
Mike Quinn's was at the Oakland, CA airport. I first saw it
in the early 1990's, I think, when it was still in the WW-II
temp building on the airport property. You were literally
walking on 3" of crunched circuit boards in the back rooms!
There were large tables covered with circuit boards and
small units, and the stuff that slid off the tables just
became the floor covering.
They had tons of boards out of computers and electronic
equipment. The best stuff was kept in front in glass cases
next to the cash register.
Jon
I recall going to Mike Quinn's and seeing
barrels of RTL.
I wish now that I'd bought a bunch of them.
Most DTL can be replace by a TTL except a few with different
pinouts and the NAND with the diode expand pin.
My oldest equipment has a mix of DTL and TTL.
Dwight
All I ever saw was the ads like this.
https://www.flickr.com/photos/oskay/4455981283/
23 Apr
23 Apr
7:10 p.m.
On 04/23/2016 04:34 PM, Brent Hilpert wrote:
> The interesting thing was that there seemed to be a distrust of LSI
> chips early on. I recall working on a project around 1973, where the
> lead engineer preferred to design his own UART from SSI rather than use
> one of the new UART chips.
>
Well, he may have been worried about availability, or
possibly the part going obsolete.
Those are other issues that a designer might be concerned
about, as well as reliability.
Jon
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bfranchuk＠jetnet.ab.ca -
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