Old-timers Needed for Retro Prop Project

Humanoido

I have a retro prop project and have searched the net looking for a post of the most recent ad in computer magazines around 1975 for the SCELBI computer. While I have have found early scanned ads from computer magazines, none of these are the more recent one. The more recent ad shows a photo of the computer with nothing on top (no boards, no expansion, i.e. it is a rectangular box with a row of toggle switches).

The Early Days of Personal Computers, Stephen B. Gray, in CREATIVE COMPUTING VOL. 10, NO. 11 / NOVEMBER 1984 / PAGE 6 said...
www.atarimagazines.com/creative/v10n11/6_The_early_days_of_persona.php
The following is taken from the only chapter written for that unpublished history, in which the Scelbi-8H was to have been an important milestone. First Advertised Personal Computer Using a Microprocessor. The first advertisement for a personal computer based on a microprocessor appeared in the March 1974 issue (p. 154) of QST, an amateur radio magazine. The ad was for the Scelbi-8H, manufactured by Scelbi Computer Consulting, Inc., of Milford, CT. Scelbi's founding father, Nat Wadsworth, was a design engineer with General DataComm Industries in Danbury, CT, when Intel gave a seminar nearby on the 8008 microprocessor. But when he and several other young engineers tried to talk management into simplifying products with the 8008, they got nowhere. Wadsworth, intrigued by the capabilities of the 8008, cornered several other company engineers and asked, "Why don't we design a nice little computer and each build our own to use at home?" Two of them agreed, and Wadsworth and Robert Findley designed most of the system.

Also does anyone knows the status of Nat Wadsworth?

humanoido

Leon

I remember it. It was featured in a book about the 8008, it had a red cover.

Leon

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Amateur radio callsign: G1HSM
Suzuki SV1000S motorcycle

Bill Henning

Here is a few links for you:

http://en.wikipedia.org/wiki/SCELBI
http://en.wikipedia.org/wiki/File:SCELBI_8H_Computer.jpg
http://userwww.sfsu.edu/~hl/c.Scelbi8H.html
http://apple2history.org/museum/computers_apple1/scelbi8h.html <-- has a jpeg of an ad

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Please use mikronauts _at_ gmail _dot_ com to contact me off-forum, my PM is almost totally full
Morpheus & Mem+dual Prop SBC w/ 512KB kit $119.95, 2MB memory IO board kit $89.95, both kits $189.95
www.mikronauts.com - my site 6.250MHz custom Crystals for running Propellers at 100MHz
Las - Large model assembler for the Propeller Largos - a feature full nano operating system for the Propeller

Fred Hawkins

Not old enough it seems. All I can offer is May 1979's Reader Service card for Byte Magazine. Circle 318 to get further information from Scelbi Computer Consulting Inc. "Just add a 15-cent stamp and drop it in the mail"...

Their display ad on page 232 was about Personal Information Management System, Z80 Instuction Handbook (Just $4.95), Calculating with BASIC, Learn Microprocessors, and the ever-popular 6800 & 8080 Software Cookbooks (Only $10.95 EACH). They seem to have been out of the hardware biz by then.

Post Edited (Fred Hawkins) : 10/14/2009 8:09:03 PM GMT

Parsec

What's the cutoff for being considered an old timer?

Humanoido

Fred Hawkins said...
Not old enough it seems. All I can offer is May 1979's Reader Service card for Byte Magazine. Circle 318 to get further information from Scelbi Computer Consulting Inc. "Just add a 15-cent stamp and drop it in the mail"... Their display ad on page 232 was about Personal Information Management System, Z80 Instuction Handbook (Just $4.95), Calculating with BASIC, Learn Microprocessors, and the ever-popular 6800 & 8080 Software Cookbooks (Only $10.95 EACH). They seem to have been out of the hardware biz by then.

By the time of 1979, they had gone into book publishing as it made more money than the SCELBI computer.
Here's something interesting. While searching for information, I came across the following in MICROCOMPUTER DIGEST .

Microcomputer Digest,Vol 2, #7 Jan, 1976, p3 said...
$90 4-BIT MICROCOMPUTER KIT
Comp-Sultants, Inc. is now offering their
MICRO 440 4-bit computer kit (PC board, Intel
4040, clock interface, 256 bytes of RAM and an
87 page manual) for only $90 in single units;
$75 in quantities greater than ten. All other
parts needed to complete the microcomputer kit
are standard and can be purchased elsewhere.
The PC boards are early-run versions without
plate-through holes. This represents a
significant savings in cost, at the expense of
having to solder the components on both sides.
For an additional $20, Comp-Sultants will
throw in the major components of the power
supply/TTY interface (PC board, transformer,
and regulators).

I looked for a photo of this computer on the web but didn't find it.
Does anyone remember the kit? Sure would like to find the manual posted somewhere!
The 4-bit computer was amazing, though soon eclipsed by the 8-bit.

humanoido

Post Edited (humanoido) : 10/15/2009 2:57:02 AM GMT

Humanoido

Parsec:

To actually remember "retro" computers, one would need to be old enough to have lived through the birth of the personal computer hobby era, which had roots 1971 and through 1974. Intel’s first microcomputer add appeared in November 1971. There are many interesting stories from this era regarding the first microcomputers, which were often built from scratch or a board and scrounged parts.

humanoido

Parsec

Bummer, I was born in 1976. I did build a Z80 based project from scrounged parts when I was 17 though, so maybe i'm a 1/3 qualifier

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No electrons were harmed while rendering this message.

Chris Savage

As someone proficient with 6502, 68xx, 680x0, Z80 and several microcontrollers this certainly has my attention. But if I got involved it would mean putting several current projects on hold again...and I have got to stop doing that.

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Chris Savage

Parallax Engineering
50 72 6F 6A 65 63 74 20 53 69 74 65
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Cluso99

*history*

I officially entered (work) electronics in 1970 and computers (Singer/ICL System Ten Engineer) in 1974. Singer released a VDU (Video Terminal) for it's computer based on an Intel 8008 and used 1702 EPROMs.

The Intel 4004 (not 4040?) was originally designed by Intel to be a smart calculator but the client rejected it saying that was not what they wanted and Intel realised what they had. I do not recall any computer kits offering the 4004 by Intel and although later recognised as the first microprocessor, at that time this was not the case. We were following preliminary microcomputer chips information in 1973, but none were available at the time. IIRC the most complex chip in 1973 was the 1757 ??? which was a full UART in a 40 pin ceramic chip. I was involved with an electronic teletype regenerator design with my boss using this chip. Previous chips were 24 pin with the UART as seperate transmitter and receiver chips.

IIRC Intel announced/released the 8080 in 1975 followed closely behind by Motorola and the 6800 in 1976. I was in the process of building an 8008 based computer when I bought a Motorola D1, followed by a D2 kit as soon as they were released in 1976. I then designed many commercial products using 6802, 68705, Z80, Z8681, etc.

*end history lesson*

As you are aware, I am fully occupied with the ZiCog/TriBlade project at the moment.

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade, RetroBlade,·TwinBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: Micros eg Altair, and Terminals eg VT100 (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm

Ale

I'm just a bit older than Parsec and only had my first computer when I was 10. So I'm not really an old-timer, but love those days where knowing meant much more than moving a pointer around and using Word...
Now, let's go back to this nice board (the Prop-CPLD thing) and see if I get it to work... (I should be working on my (chemistry) thesis... electronics can me).

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Visit some of my articles at Propeller Wiki:
MATH on the propeller propeller.wikispaces.com/MATH
pPropQL: propeller.wikispaces.com/pPropQL
pPropQL020: propeller.wikispaces.com/pPropQL020
OMU for the pPropQL/020 propeller.wikispaces.com/OMU

heater

humanoido, Sorry can't help with info but have to ask what actually is the project here ?

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For me, the past is not over yet.

Humanoido

heater:

The project(s) involve the simulation of retro computers (1971 - 1974) in terms of hardware and software, and to recall some of the early stories and gold treasured information that "Old timers" have in memory and are willing and able to share. It is often that these insights, impressions, and techniques of yesteryear are lost, yet they should remain an important part of thinking and knowledge today. For example, we went to the Moon, yet there are few people in NASA that were a part of this team (if any) that can recreate the Saturn V Moon rocket to take us there again. We must reinvent the technology. Perhaps if we had actual duplicates or simulated duplicates, the great journey of returning to the Moon would be less compromised, more equitable and economical. Of course, you will say, "why not just imitate the Atari, Apple, Tandy TRS-80, MITS Altair, or some more popular computers?" I think it is equally, if not more, productive, creative, and beneficial to additionally show recognition and remembrance of those very early microcomputers which, although were less popular, still remain a very important and undeniable link to paving the way towards the evolution of today's microcomputer.

humanoido

Humanoido

It is also really cool that some of us can actually share the excitement of the microcomputer hobby era with today's young people, showing not only the importance of history but pave a mind set towards the future.

humanoido

Toby Seckshund

I suppose I get close to old (b 1958) but I, along with most people of that era, just didn't have that sort of money around to splash out on toys. Wireless World ran a series on a Z80 based system, which turned into a commertial project, the Nasco Mk1 (always known just as Nascom1 ). It had to be constucted, had no PSU (4 rails req), less than 1Kb user ram but did give video out alond with a proper keyboard (magnetic saturation ). It cost over 1 month's salary, my father told me I was a prat.

When an application presented itself, in a chemical treatment bed my father designed, they wouldn't use it as it was too new and unproven, and used an indexed disk which was awful. My father told me I was still a ...

Come on chaps, help me get that killer app that impresses my father!

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Style and grace : Nil point

heater

humanoido.

Yep, I totally agree with you. That's why I originally wanted to put together a MITS Altair lookalike. I was fascinated with the idea of compiling and running CP/M from the actual original sources and then being able to run those old programs on it. Not to mention toggling in code using the front panel switches and blinken lights. Kind of "software archeology". The Altair hardware part of this plan is a bit on hold as we sort out ZiCog on the TriBlade etc etc.

There seem to be many people who feel like this given the number of simulators that have been created for CP/M machines, Apples, old games machines etc etc. What's generally missing is the physical hardware experience.

One of the most amazing examples is the Apollo guidance computer emulator. You can down load compile and run the original Apollo guidance software. www.ibiblio.org/apollo

I thought I was going back in time far enough looking at the Altair. I'd never heard of the Scelbi-8H.

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For me, the past is not over yet.

Toby Seckshund

Heater

We are getting close to the abucus jokes again !

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Style and grace : Nil point

heater

Yep, but no one is going to want to blow up my abacus when I leave it on the bus.

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For me, the past is not over yet.

Cluso99

humanoido:

There were no microcomputers until about 1975-6. Prior to that, the smallest were minicomputers based on TTL, DTL and transistors and used core (ferrite rings) for memory. The NASA moon computer would not have been regarded as a microcomputer at the time. Microcomputers were coined when the first microcomputer chips evolved. People started to build 8008 based computers, but to my knowledge, most, if not all were abandoned in favour of the Intel 8080 and Motorola 6800 as the support circuitry was far too complicated. So by the time hobbyists (myself included) got the parts together (saved the cash for the bits) the 8080 and 6800 killed them.

I have emulated a 1969-1993 (supported to 2000) Friden/Singer/ICL System Ten and System 25 around 1990 using a 33MHz 486 computer. It ran 3x the speed with maximum memory and disks for the current model. It was commercially validated.

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade, RetroBlade,·TwinBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: Micros eg Altair, and Terminals eg VT100 (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm

Toby Seckshund

Clusso

I remember a computer at my first place of work, in 1974, that looked like a chest freezer without the cold bits. There were cards slotted everywhere that had just a couple of transistor flip-flops on each. Whilst it was big I just couldn't see how it had enough gates etc to run Cobal, perhaps there was other parts I never got to see.

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Style and grace : Nil point

Leon

Parsec said...
What's the cutoff for being considered an old timer?

I suppose I'm a real old timer at 67. I saw my first computer, an English Electric valve/tube DEUCE, when I was nine years old, at the Science Museum in London, at the time of the 1951 Exhibition. It was playing Nim against visitors (acms.synonet.com/deuce/zv08.pdf), and we joined the, very long, queue. It was obviously going to take over an hour for my turn so my parents gave up and took me home after a few minutes. I subsequently joined English Electric, Kidsgrove, as a student apprentice 10 years later; they still had a working DEUCE. It was decommissioned a year later and donated to Staffordshire College of Technology, where the aforementioned document came from. The program was written directly in machine code; a form of assembly language called Autocode was subsequently developed, which made things much easier.

Leon

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Amateur radio callsign: G1HSM
Suzuki SV1000S motorcycle

Post Edited (Leon) : 10/17/2009 1:26:50 PM GMT

Toby Seckshund

I did get hold of a ferrite ring matrix a long time ago, but sram finally became available so I never did any thing electrical with it.

Good picture for macro-photography though!

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Style and grace : Nil point

heater

Wow, Toby. Please put the pictures up for us.

I wanted to by a ferrite ring memory from an electronics surplus store on the Edgeware Road about 1970. Just didn't have enough pocket money that day.

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For me, the past is not over yet.

Toby Seckshund

Sadly it was on 35mm, 35 years ago. Got qdos from the art teacher. My parents beggered off to the south coast in '83 and the matrix along with pics got lost/chucked .

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Style and grace : Nil point

Humanoido

There was an ad with a SCELBI kit at a very attractive price. I always wanted one but somehow missed it. I later thought I could pick one up on ebay but the version I wanted never appeared. When the RCA CDP1802 MPU chip came out, I devoted all my attention to building a microcomputer around it. This chip was popular as NASA had several spacecraft, including Voyager, that used it. The 1802 chip led to several popular microcomputer kits such as the COSMAC ELF, a How To Build series was run in the August 1976 edition of Popular Electronics (with other part series that followed), the NETRONICS Elf II, the RCA VIP, the Quest Super Elf, and others. There are several emulations available, as well as the original source code and numerous support documents. I think an emulator would be possible for the Propeller chip.

www.cosmacelf.com/history1.htm

http://www.decodesystems.com/cosmac/index.html said...
The RCA CDP1802 COSMAC microprocessor is a one-chip CMOS 8-bit register-oriented central processing unit introduced in 1976. Although the 1802 is now more than 30 years old, it continues to prove itself in many industrial and commercial applications. It is also the furthest microprocessor from Earth, having been used on board the Voyager spacecraft. (Voyager 1 is now the furthest human-made object from the Earth, at more than 100 A.U. distance.) Certain versions of the chip were extremely resistant to cosmic ray upset, making it well-suited for use in space.

The 1802 was first popularized for hobby use in a 1976 Popular Electronics article that described the "COSMAC Elf" computer. Around the same time commercial companies began offering similar products based on the 1802. The 1802 is interesting for a number of reasons, not the least of which is the fact that it uses static CMOS circuitry, meaning it has no minimum clock frequency. Also, most instructions execute in two clock cycles. It has sixteen general purpose registers, each of which are 16 bits wide. Any of these registers can be used as a program counter or an accumulator.

humanoido

heater

It looks like you can still by a a COSMAC ELF kit here www.sparetimegizmos.com/Hardware/Elf2K.htm#Build%20Your%20Own

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For me, the past is not over yet.

Cluso99

I threw a lot of core memory out in 2000 :-(
The computer pcbs were shipped to China to recover the gold.

I bought a second hand Singer System Ten in 1977 (18 months old). It was the length of my garage, and I insulated the walls and a/c. I maintained it until 2000. It saved me having to organise free computer time for programming from 1am-5am each day. A 10MB disk (spelt "disc" then) was the size of a washing machine and was worth A$16,000 ea new in 1976 - I had 4 ! I also had the maximum core memory - 110Kx6 bits. IIRC it had a parity bit also. Core was worth $6,000 per 10Kx6.

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Links to other interesting threads:

· Home of the MultiBladeProps: TriBlade,·RamBlade, RetroBlade,·TwinBlade,·SixBlade, website
· Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
· Prop Tools under Development or Completed (Index)
· Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
· Search the Propeller forums·(uses advanced Google search)
My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm

localroger

I have a COSMAC Super ELF which was handed down to me around 1983 by the slightly older guy who built it. I'm technically just old enough to have bought and built it myself -- I would have been about 14 years old -- but I didn't have the money or the tools to assemble and troubleshoot such a complex kit at that age. It still works. After it sat in a box for years I finally figured out what to do with it -- I had it framed. (And yes, the frame hinges open and I ran the power plug to the outside world so it can technically still be used.) But I like to glance at it occasionally (glances) to remind myself how far things have come in the last 30 years.

It has occurred to me that it should be possible for a Prop to completely emulate this little fellow, including its expansion memory and video output, without any support chips at all (which is especially amusing since the original Super ELF has over 30 IC's in addition to its 1802 CPU). The problem is, I still wouldn't have any practical use for it.

Humanoido

I built the COSMAC ELF from scratch, using the plans in Popular Electronics. It was a one board computer and more fun than you can imagine. The second COSMAC ELF I built could do a lot more, with RAM, video generator, RF modulator, full size keyboard, Kansas City Standard Tape Cassette, parallel dot matrix ink printer, and Tom Pittman's TINY BASIC.

I remember building up many software routines to compensate floating point, mathematical routines, fast sorts, scientific plots and graphics. I even wrote some games in real time like Lunar Lander. For the first big project, it was converted to a car computer, complete with video maps displayed on the small portable 5-inch SONY TV along with calculated distances and various parameters while interfaced to the car. I believe it was the first car computer but I never manufactured it for that purpose - it was a project strictly for my own use during long trips.

The next big project, it calculated the mathematics and formula for machines to generate giant optics automatically. The results from this project were astounding and published in the news. Then next project calculated the position of the Star of Bethlehem and plotted a star field with constellations and Bethlehem graphics. I called it my time travel project. With the project, even more interesting, I found another "Star of Bethlehem" that will appear in the future. Results were published.

Over the years there were many more exciting projects created with this amazing home built computer. Here's the good news: a Propeller chip can already run TINY BASIC (see the HYDRA CD). Plus, the "video modulator" is already built into the chip, so to speak. It could be a simple matter to change it to the Tom Pittman version, using the 128K card. The original 68K version listing of Tom Pittman TINY Basic (from the HEX dump listing) is here: www.ittybittycomputers.com/IttyBitty/TinyBasic/TB68R.txt

My idea is a little different. I think the emulation can take place with the TINY BASIC language and not at the 1802 chip emulation level. This could be a much more simple project. Is anyone with me on this???

humanoido

Post Edited (humanoido) : 10/18/2009 7:17:17 PM GMT

Humanoido

For getting started on the Propeller 1802 simulated language project, the following Tiny Basic Manual is helpful because it contains a list of commands from the 1802 version. I expect the USR function with any addresses and registers would be irrelevant.

www.ittybittycomputers.com/IttyBitty/TinyBasic/TBuserMan.txt

humanoido

Humanoido

TINY BASIC can fit into 2 or 3 K of memory. It may be interesting to engage multiple Propeller chip versions (run by each cog) and communicate together.

en.wikipedia.org/wiki/Tiny_BASIC

The TINY BASIC Experimenter's Kit

users.telenet.be/kim1-6502/tinybasic/tbek.html

humanoido

Post Edited (humanoido) : 10/19/2009 4:16:37 AM GMT