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Vintage Computers Any vintage computer systems, calculators, video games etc., but with an emphasis on 1980s and earlier equipment.

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Old 27th Jun 2024, 12:26 pm   #21
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Default Re: Intellec 8 Mod 80

Hi Jones - welcome to the forum, you will fit right in here. As Owen mentioned your first few posts will be held for moderation, but that will wear off after a while.

A unified request to the museum might help.
Good idea, maybe those interested should form an 'Intellec User Group' for the specific purpose of approaching museums etc for help with information and any other resources they may be willing to share.

While I'm not saying they won't try to help individuals (Realtime seems to have had a decent response when asking for info about his SC/MP development system) common sense / allowance for human nature suggests they are more likely to respond if they feel they will be helping out a group of interested people rather than just one individual.
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Old 27th Jun 2024, 4:06 pm   #22
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Location: Biggin Hill, London, UK.
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Default Re: Intellec 8 Mod 80

Originally Posted by jonesthechip View Post
Just found this fine web forum after a little light searching for 'Intellec 8 mod 80' microcomputers. I'm restoring an Intellec 4 mod 40 (from my college days) and I'm missing the native assembler tape. (WTH didn't I keep a copy from 50 years ago?) I'd spotted the museum copy of the 8080 assembler early last year and I've been asking them nicely if a copy (paper or electronic) could be made. The idea would be to reverse engineer the tape contents to see how the assembler worked and then roll my own 4040 flavour. Seeing that there are a number of enthusiasts with 8 mod 80 boxes in the UK, and elsewhere on the planet, having the actual assembler would complete their systems. A unified request to the museum might help. Any information gleaned from the tape would be shared as source code and a hex file.
Regarding hardware, I've built a 20mA current loop <> USB serial adapter to pretend to be a 33ASR, and a high-speed tape interface that uses an Arduino.
To aid writing the 4040 code I've coerced a Teensy 4.1 to emulate the intellec 4 mod 40 and execute 4040 code at the correct rate. A lightbulb moment arose when I realised that the Teensy could be made to emulate similar vintage intellecs, such as those withe 8008 and 8080 processors.
If anybody has any thoughts on where to look for original paper tapes for these wonderful beasts, please get in contact!
I am sure you have it, but the schematics for the Intellec 4 Mod 40 are on bitsavers (may be hiding in the 'components' section).

I built a 20mA loop <-> RS232 interface for my Intellec shortly after I got it. I normally use it now with an HP Palmtop as the terminal, this has the advantage it can capture/store the received data from the Intellec and II can then transfer it with kermit to something more modern. I don't have space for a modern PC on my workbench.

Not having the original high-speed paper tape punch/reader I built interfaces to a Facit 4070 punch and Trend UDR700 reader. However if you're prepared to share the design details, I'd be interested in seeing your Arduino-based interface.
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Old 27th Jun 2024, 6:28 pm   #23
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Location: Northampton, Northamptonshire, UK.
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Default Re: Intellec 8 Mod 80

When I had a quick look earlier, I did find quite a bit of info on the Intellec 4 MOD 40 etc. including a post from jonesthechip on VCFED in Jan 2023 asking about the Paper-Tape based 4040 RAM-Resident Editor-Assembler that originally came with these units. But it didn't seem to get much of a reply, from anyone who actually had this.

I note that the https://en.wikipedia/org/wiki/Intellec page mentions Tony Duell!

And it seems MAME emulates these Intellec units: https:://
- But maybe MAME only has the unit's original firmware and not the additional software.

On Herb Johnson seems to have acquired several of these units. And he does have lots of downloads on there, like the ROM Dumps:
But I couldn't see the Editor-Assembler so it may be worth contacting him about it.
- Although I've also found Herb Johnson himself asking for this at: in Dec 2022.

Various downloads of scanned manulas for the Intellec etc are here:

But I've yet to find the code for the originally-supplied paper-tape Editor-Assembler.

It seemed if you had originally joined Intel's MCS user Club / Library, you got given access to all of the source code.
With a list of some of the contents Herb Johnson got from the Lawrence Hale collection, at:

And Intel produced a Cross-assembler in ANSI-FORTRAN (MAC4 for the MCS-40) for you to run on whatever particular system you had. With that probably being more available online these days (even if it originally came on reels of magnetic tape that may be harder to work out the format compared to being able to see it on paper tape)
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Old 30th Jun 2024, 9:30 am   #24
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Location: Wrexham, Wrexham County Borough, Wales, UK.
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Default Re: Intellec 8 Mod 80

FYI I have a complete set of the original info for the intellec 4 mod 40, and one hell of as lot of intel MDS series II/III manuals.
As regards asking the museum nicely for a copy of the tape, a group approach would be a good idea. They've been friendly in their replies, just need to incentivise them to do the job. I'd even chip in a (small) sum of Australian beer tokens if a monetary offer was made...
In other news, I've made an Arduino emulator for a high-speed paper tape interface for the intellec boxes. It's a little crude, simply loads HEX that's part of the compiled programme but the electronics works just needs a bit more effort on the sketch software. The actual intellec communicates via some opto interfaces and an Atmel processor (to swap 110<>300 baud) into a TTL/USB serial interface. I'll get a circuit diagram together...
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