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What good are S-100 systems for?

Eudimorphodon said:
The bus is really oddly laid out (that whole deal with the bipolar data bus alone.
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I'm not certain what you mean by this--do you mean splitting the input and output data buses? At least one implementation just tied the two together. That was odd, considering that the 8080 CPU had a bidirectional data bus. Perhaps the idea was to simplify things, but in practice, it didn't work out that way.
 
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Chuck(G) said:
I'm not certain what you mean by this--do you mean splitting the input and output data buses?
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Yes. I think the SOL-20 might have been one of the first machines to violate the “standard” by bridging them, and then IEEE-696 has the option of using the redundant pins as a 16 bit extension but, yeah, it’s a mess.

My vague understanding of why they did it on the Altair is it simplified some aspect of the front panel implementation? Of course in the end most S100 machines didn’t have one anyway, so I guess that maybe wasn’t the most forward looking decision.
 
When I got my SOL-20, I knew nothing about the S-100 bus. But in no time I has the N* controller card running with Mike Douglas's VSG and had CPM running. I put nice new 5.25" dives in an enclosure with the VSG. I like the way the N* card was "plug & Play":


Then I was able to write and assemble programs, make S-100 cards and have a lot of fun that way .. To me at least, an S-100 computer is an experimenter's dream.
 
One other thing I had fun with with my SOL, was I used up a section of spare memory address space to add some ROM's and to do it I made replica SOL-20 personality modules with a simple glue logic interface and put some programs in there.

A MEMTEST program (always scan your memory before using an S-100 computer because if things don't work, it could well be the RAM, especially if it is the PT 16KRA DRAM boards).

Also the TRAIN program.

Since the Sol's personality module had been called the SOL's "Brain", I called it the Three Brains project. Like on the Austin Power's movie where Dr. Evil explained that he put a Laser Tractor Beam system on the Moon, designed by Dr. Alan and Dr Parsons, so he decided to call it The "Alan Parson's project", until Scott corrected him by explaining they were a progressive rock band.

 
I came across this thread and original post from early July. Time has passed by this discussion, but I don't think the questions of the original post were fully addressed, in my opinion of course. There's an off-topic question about the transaction, and an on-topic question about some unknown system presumably "S-100". I'm curious to know, what the thing actually is/was.

The off topic question is about a transaction that did not complete, and left a middle-person with a box of something not intended for them personally. It seems to me, the polite thing to do (if not already done), is to contact the original buyer and seller, confirm a resolution with them *at their expense*. Otherwise, it's a private transaction. The point likely intended was to say "I really don't know what this thing is at the moment".

On-topic, a person possesses an unknown system likely S-100. The obvious response is: determine the identity of the system and contents. Take photos and post them, or use the photos to Web search to identify the thing. Once indentified in some postings, someone searching the Web for those items will have some responses. Then the specific merits of the specific items can be discussed.

As far as the side issue, of the merits today of some S-100 system? (shrug) that depends on so many things. Many hundreds of S-100 models and board-products were produced in the 20 years after the Altair 8800. The empirical response, is that some people today still find S-100 systems interesting, enjoy working to restore them to some kind of operation. Others find particular S-100 items of more value than others and trade in them. Others participated in their original use or even production and design, they have responses. Some produce new S-100 compatible boards. So they are items of technical history and people respond in different ways. Vague question, vague answers.

Also: no details, no responses. Find the details, post them. Good luck to the original poster in resolving this thing as suggested.

regards Herb Johnson
kinda known for S-100 stuff
 
Hi,

I've done some experimenting with my Altair 8800 and plan to put it to work controller mobile art projects:



.
 
One of the first applications that I saw for a PC was an IMSAI 8080 running a plastic vacuum forming lashup. It worked, although it seemed a bit Rube Goldbergish.
 
I have been an S100 user from about 1984 onwards. Yes a bit late to the game but it wasn't the bus that drew me to it. I wanted to run Cromix and that was the only way. It served me well up until IBM clones could run something similarly useful. But in more recent times I have had an on again off again kind of relationship with S100. Sometimes I hate it for the mentioned reasons...the horrible bus layout, the 8080 signals, the regulators, etc. Sometimes nostalgia gets the better of me and I warm up to it again. Right now I am in the warm phase and looking to get my Z2 restored and expanded. Ultimately I would like to get an ATA hard drive interface and a driver written for Z80 Cromix. Plenty of fun to be had.
 
What good are S-100 systems for....? Well, I suspect that if you had one and used it, in the early going, then you are probably flirting with your 'golden years'. That said, there is a lot of value in the keeping your body and mind active. And that is a good thing, and the driving force behind the 'hybrid' S-100 I'm putting together. It is based on a Z-80 SBC design, which I have 'ported' to the STD bus so far, and now on to the S-100. My S-100 hybrid is 100% wire wrapped and I'm even going to have a dual boot capability; one for 64K CP/M using serial I/O, and the other for 62K CP/M with an parallel ascii keyboard and a video card. Both will have serial ports, one dedicated for connection to an IBM PS/2 'file server' and the other to a terminal, a Centronics printer port, and a RAMdisk. Will I ever get finished with the thing? I hope not. Even when I run out of hardware things to design and build, there are countless programs I can write; a word processor, a spreadsheet, custom programs for custom cards.

Do I need or require all this effort & stuff? No, maybe not really. But in a way I do. It keeps my brain and hands active. And it keeps me connected and engaged like I am right now with all the people here at VCF. And hopefully at some point I can get my backside to a VCF event. The vintage/retro community is an incredible community of people, and that is what S-100 computers are good for. :)
 
Hi,

I am running the world's first BBS CBBS on my IMSAI-JAIR computer at the moment. I had this setup on my Altair 8800c computer and I've been documenting everything on my website; https://www.brainless.org/Altair/

I've also written a few programs in MBASIC/BASIC-80 as I learn the language.

Bottom line is, the S-100 hobby is an education and great to keep busy in retirement. A little pricey at the start (about $1,200 to build an Altair 8800c computer), but cheaper than paying for the education anywhere else.


.
 
Don't think I haven't looked into one. :ROFLMAO: If I could find one that had a Z-80..... But, since the first computer I ever touched was an Intel 80/20, I would not go the wire-wrap route.... Maybe some day....
 
S100 always seemed to be a bit haphazard to me. The IEEE 696 standard came out far too late to have any significant effect. And now it's withdrawn.
Mutlibus, on the other hand, appears to have had a lot of forward thinking in its design.
 
Chuck(G) said:
S100 always seemed to be a bit haphazard to me. The IEEE 696 standard came out far too late to have any significant effect. And now it's withdrawn.
Mutlibus, on the other hand, appears to have had a lot of forward thinking in its design.
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The interesting thing I found out about the S-100 bus, despite its vagaries and peculiarities and the plethora of signals, it is quite easy to make a home grown S-100 card (for a novice like myself) that works on the bus with a minimum number of the control signals.

At first (because I had never seen this bus before I got my SOL) I was a little overwhelmed by the number of signals on the bus, especially on dynamic memory cards too. That was until I saw what Seattle Computers did with their 16k standard static Ram card, and how to interface with the S-100 bus, equally as simply, if not simpler, than an ISA bus in a vintage computer like the IBM 5155 which I had been doing before I got my SOL-20.
 
Many of the signals on the S100 bus aren't needed for simple things. At one point, I used readily-available 44 pin prototype cards to do I/O interfacing--there's more than enough on those 44 lines to do that. I recall that Intel even made use of mezzanine boards for some things.
 
Pepinno said:
But, but... Did the OP @ardent-blue ever get to open the box containing the S-100 computer?
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Looking at the original post, I think CHAT GPT confabulated the entire story (joking of course).

After working with it for a while, I got it to confabulate data, when it had no definite answer, so it was already half way there.

I also got CHAT GPT to admit that if there were 100 people in one building and 10 people elsewhere and disaster could be avoided with help from Chat GPT; it had to make an output or response (and had no time to consult its designers and the usual authorities couldn't help) and it could only save one group of people alone, it concluded it would save the 100 over the 10. A typical result from a difference engine. But I didn't have the heart to tell it, the 10 were children in a day care facility and the 100 were end stage geriatrics in a hospital. It all sounds very iRobot.

Now that would really be a challenge, build an AI onto an S-100 board.
 
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Classic Trolley Problem. Classic response. Not necessarily a simple numeric response. But of course could be ... so try to get ChatCPT to explain it's rationale ("reasoning") for its answer ...
 
I think Eliza is more useful than Chat GPT. At least, Eliza will never provide completely incorrect responses.
 
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