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View Full Version : A New Single Board Z80 based S100 bus board for first time users



monahan_z
November 13th, 2015, 03:55 PM
I’m delighted to announce that the Z80 SBC S100 bus computer board arrived this week and as best as I can tell is working perfectly fine. With 70 boards here that’s somewhat of a relief!

I have written up an extensive description and blow by blow assembly notes which can be seen here:-
http://s100computers.com/My%20System%20Pages/SBC%20Z80%20Board/SBC%20Z80%20CPU%20Board.htm

The board even works up to 8MHz – at least in my system with no wait states. The main change from the earlier prototype was I lowered the height of the IDE/CF card adaptor and better labeled the silkscreen.

This board should really help first time users get a functional system up and running. It has 128K of RAM and a way to switch the lowest 32K for use with CPM3. The Z80 monitor has routines to read and write sectors on the CF card and there is an XModem routine to download (binary) files from a PC and place them anywhere in RAM for execution.

So everything is there for somebody to write an efficient CPM3 BIOS. A CF-CARD image could be uploaded into a ZIP file so anybody could immediately have a functional CPM3 system. We need some volunteers for this potentially very useful software.

The board has numerous jumpers and can later on be morphed into a more extensive S100 multi-board system. It is however built as a starter S100 board.

I have double checked my build instructions but I might have missed something. If you see an error as you do yours please let me know.

Let’s at least for now keep all treads related to this board on the Google Groups S100Computers forum

Below is my current mailing list. I have got all your addresses except Rich Camarda. Rick please send me your address ASAP. If you are not on the list please let me know immediately by private e-mail. Do not send payments until you get your board(s). There will be instructions in the package.

Fabio Battaglia 3
Paul Birkel 2
Pete Plank 1
Todd Goodman 3
Alex Jacocks 1
Jeff Albrecht 2
Gary Kaufman 3
Matthew Turner 3
Rich Camarda* 2
Howard Feindel 2
Leonard Young 2
Robert Greenstreet 1
Pierre ROUSSIERE 1
Steve Jones 1
Vince Mulhollon 2
Dylan McNamee 1
Rob Doyle 1
Santo Nucifora* 3

Roger Hanscom 2
John Reeves 1
Jeff Galinat 2
David Ray 1
Jack Rubin 1
Tim Acker 1
Harold Rothwell 2
Neil Breeden 3
Rick Bromagem 2
Andrew Quinn 2
Brian Marstella 2
Jim Orchard* 1
Ian May 2
Greg Beat 1
Richard P McCoy 1
Wayne Warthen 2
William Dromgoole 1
Michael Narigon 2
Dave London 1
Dennis Bernardo D'Annunzio 1

MicroStrand
December 17th, 2015, 12:52 AM
The SBC-board is great, but the website s100Computers.com becomes as a whole more and more chaotic! Broken links, lots of typos, inconsistencies on several pages in format and descriptions, bad XHTML code, etc.! The site has lots of informations, but is on the other hand full of confusing errors. My advice: take some time for maintenance before you publish something!!! :confused:

glitch
December 17th, 2015, 06:13 AM
The SBC-board is great, but the website s100Computers.com becomes as a whole more and more chaotic! Broken links, lots of typos, inconsistencies on several pages in format and descriptions, bad XHTML code, etc.! The site has lots of informations, but is on the other hand full of confusing errors. My advice: take some time for maintenance before you publish something!!! :confused:

Sounds like an offer to rewrite it and take over maintenance!

monahan_z
December 17th, 2015, 11:42 AM
Currently the site folder on my computer is 3.98 GB. Unfortunately my goal is not to maintain a "cutting edge"/commercial style web site -- I just cannot devote that amount of time -- sorry. The main function is twofold:-
1. Act as a central source for information on old/original S100 boards and if possible make available for downloads the relevant manual in pdf format. This has involved the collection of information from many, many sites and private donations. It’s by no means complete but as far as I’m aware the only location for the largest collection free S100 bus board manuals (.pdf files).

2. The second is completely different and actually the main function of the site; it contains a collection of new S100 boards put together by myself and others that utilize the S100 bus to incorporate new circuits. Early boards were essentially reproductions of old S100 boards tweaked here and there. Newer boards are more complex aimed at utilizing the fuller capabilities of the IEEE-696 bus standard including multiprocessor arrangements. This has now involved adding an “overhead bus” connector to the boards to allow the use of 32 bit CPU and 4GB memory addressing. So far this has involved the production of about forty new S100 boards. However looking around here there must be at least 100 different prototype boards to get these as final versions. I spend probably 30 hours a week on the above and whiles others probably don’t spend as much time into the effort, their contributions are considerable.



There is now a hard core of users (a number overseas) that “play” with these boards and help others get started. While there is a growing software section to support the above, it is not a software depository site – there are many excellent ones out there.
As to errors etc. I generally set aside a slot Saturday mornings to add Web updates, corrections etc. (If I’m not traveling. I unfortunately travel overseas a lot). If you (or others) out there see an error, have a picture or pdf file for a board you wish to add/correct please e-mail directly (monahan AT vitasoft DOT org).
John

glitch
December 17th, 2015, 12:39 PM
One thing to note about this board: if you're planning on using it to troubleshoot a really early S100 system, you may run into issues if the original system was 8080-based. For instance, MITS 16K static RAM boards decode the 8080 state lines as part of their operation, and no CPU board other than an 8080 with the full state lines brought to the edge connector can satisfy that requirement. I seem to remember having a S-100 EPROM burner that wouldn't work with anything else as well, possibly due to how it accomplished burning (extremely long wait states).

Otherwise, a known-good SBC is probably the best way to test boards in isolation or whole systems. I personally use a Vector Graphic ZCB, but with a new board you'll be less likely to have problems with your SBC.

MicroStrand
December 18th, 2015, 01:09 AM
John, it is absolutely not necessary to explain what the site is good for, everybody knows it. It is the extreme huge amount of disturbing errors on nearly every single page. If I would start to proofread all your stuff, then it would be necessary with great certainty, to send you every week a whole list of errors. I understand that your time is limited, in this case it would be much better to hire someone with the maintenance of the site, instead of constantly waiting for anyone to do it for you in "baby-steps". A technical subject requires in principle for a high degree of accuracy in the descriptions, wherein it does not matter whether this happens in your free time or in your job. The reliability of information is an essential factor. The present condition in any case is an imposition and is not suited to create confidence in your work for the interested reader. :???:

Therefore, once again a reminder, you are the author and as such responsible for the publication of the pages! And a clean design and maintenance of sites has nothing whatsoever to do with a professional profile, it is rather a measure to problem avoidance and much less time consuming than you may think!

Tor
December 18th, 2015, 05:21 AM
Hmm.. I'm browsing s100computers.com from time to time, so I did that just again, and as is normal everything I did worked fine and I found what I expected to find. If there are issues they're probably very subtle. I have much more trouble with the google groups-based or even wiki-based sites (related to these boards) which to me are a bit information constrained. But I'm ok with s100computers.com, I don't see any big, or even medium problems.

ef1j91
December 18th, 2015, 05:26 AM
Not to hijack this thread further, but other than the occasional minor typo / misspelling, S100computers.com is a treasure-trove of information. It's certainly not "chaotic"!

smp
December 18th, 2015, 06:12 AM
Hmm.. I'm browsing s100computers.com from time to time, so I did that just again, and as is normal everything I did worked fine and I found what I expected to find. If there are issues they're probably very subtle.

Hear, hear! This is what I find when I browse www.s100computers.com, also. I'm sure that I have occasionally run across a broken or bad link, but most assuredly not the many bad links on every page that MicroStrand is indicating.

Many thanks to John Monahan for an outstanding resource. Please keep up the great work, John.

smp

Marty
December 18th, 2015, 06:43 AM
Hi All;

I agree with SMP and the other positive comments..

I have bought three Boards from John and crew, a Z80 Board, And an I/O Board and the Floppy Controller..

I have had NO trouble with them, nor with getting Help from John ..

Many thanks to John Monahan for an outstanding resource. Please keep up the great work, John.

I have nothing but PRAISE for them..

THANK YOU Marty

glitch
December 18th, 2015, 07:01 AM
It's a little chaotic, but it's also simple. Only problem I've had is searching for S100 board info using CTRL + F and thinking it's not available because it's in a broader subcategory (i.e. Godbout/Compupro EconoRAM boards). Not really a problem, in my mind.

I've submitted better board pictures on a few pages where John has requested them. IMO, the big thing to remember with sites like s100computers.com is that this is someone using their personal time to provide free information to the community. It's not some company that you're paying for services. If it comes to investing more time in making s100computer.com "professional" vs. working on S100 stuff, I'd rather John spend his time working on S100 stuff!

monahan_z
December 18th, 2015, 09:13 AM
Thanks for the support guy’s; I'll just ignore Micro Strand. He's new here and I suspect could never be satisfied. That said, one day I will try and double back and brush up some of the "high hits" pages. The pictures on the index page for example could do with an upgrade. They were originally put there with low resolution to accommodate the lower internet speeds of the time.
While I have you…. I am doing 10 hour stints these days to get new 80386 CPLD based CPU board done. A final version in due to arrive from China on Monday. Think you will like it. Almost every S100 signal is programmable in the CPLD. I will also be announcing a new 16MB Static RAM board. This is an extension of the past GAL based V5 board. It is not only a cleanup of that board but I have redone the 8/16 bit circuit for faster access taking full advantage of the two GAL’s. All the chips on the current V5 board can just be moved across to the new (V6) board.
I also did a new version of the 32/64MG daughter board for the above 80386 board. This time one GAL will do the trick. Unlike the original board this time you have a choice (like the above 16MB board) of using four Mezzanine boards OR soldering the SMD RAM chips directly to the board. I was worried about the many small traces/complexity on this board and so also did a board with just the Mezzanine boards alone, but with very wide/thick traces. So far I have not seen any advantage of the latter.
The corresponding 80486 board is still in the works - probably end of January.
Could I have people think after that what they would like to see next? I have a prototype Raspberry Pi SIMM ARM CPU module in the works. The S100 board would be its motherboard and allow control of all S100 signals. Could run Raspian etc. in an “S100” system and/or use it as a very intelligent HMDI video terminal. Toying with doing the same for the Edison CPU module, but I would welcome ideas/discussion for other boards. How for example do people feel about a HDisk controller for a Seagate 8” hard disk where you can see the head/disk movements – fun to watch – usefulness???
John
PS don’t request boards yet. I will send out notices when they are ready.

kyeakel
December 18th, 2015, 11:48 AM
John,
What I have always thought would be a nice to have, is a S-100 board that has a processor with a built in debug mode. I worked on some embedded stuff in the past that used Motorola HCS12 processors that had on-chip debug, and trigger and trace modules. Maybe the ARM chip from the Raspberry Pi has this?

Kipp

monahan_z
December 18th, 2015, 06:54 PM
Actually the Raspberry board should be able to do this in spades Kipp. The trick is in the programming. Does anybody out there have experience programming the Raspberry in say C++. In particular you have to program a LOT of pins.

John