S100 Computers

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New S-100 Boards 
This section of this web site lists of many of the new S-100 boards I and others have recently constructed.  Still utilizing the basic IEEE-696 S100 bus format, we are incorporating modern designs into these new S100 bus boards.  The long term goal being to adapt most major microprocessor chips (and support IC''s) to the S-100 bus.   We have for example S-100 boards with master and slave CPU's like the 8086, 80286, 80386, 80486 family, the 68000/68030 Motorola family, the PDP11, all the way up to more recent CPU's like the Edison SoC.  This has been, and will continue to be, a multi-year project.  A core of enthusiastic people have got together to do this.  

Index Table Of New S-100 Boards Described on this Web Site.  
As new additional prototype and final S-100 boards are made they will be documented here:-a
          
S100 Board debugging for beginners
IDE to Hard Disk Controller Board
IBM PC keyboard to ASCII S-100 Converter board
  4 Megabyte S100 Static RAM Board
  S-100 Bus System Monitor Board
Interrupt Controller and Clock/Calendar board
  S-100 Bus Extender Board
EPROM/RAM Board
  S-100 Bus Prototype Board
  Serial I/O Board (with Speech Chip Synthesis and USB Port)
  Z80 CPU Board
  ZFDC Board (A Z80 based FDC board utilizing the Western Digital 2793)
A Propeller Driven Console IO board.
8086 CPU Board  
  68000/68010 CPU Board
  A MS-DOS Hardware Support S100 Board
  6502 CPU Board
  8088 Master/Slave CPU Board
  80286 CPU Board
  LAVA-10 SVGA Video Board
  80386 CPU Board
  S100 Bus Terminator & Prototype Board
  MSX Compatible VDP Video Board
  IBM-PC ISA bus to S-100 bus converter board
  Parallel Ports I/O Board
  V2 - Z80 Master/Slave CPU Board
  V2 - 80286 Master/Slave CPU Board
  V2 - MSDOS Support Board
  V3 - MSDOS Support Board
  16MB Static RAM Board
  V2 - System Monitor Board
  V2 - Version of MSDOS Support board
  8 MB Static RAM Board (for 80386 board)
  32 MB Static RAM Board (for 80386 board)
8080A CPU Board
S100 Bus Front Panel Control Board
V6 - 16 MB Static RAM Board
  8 Bit VGA Video Board
  V2 - Version of EPROM/RAM Board
  V2 - 80386 CPU Board
  MEM8Plus Board
  Z80 SBC Board
  OPL3 Game/Serial Board
  Introduction to the 8MB Mezzanine RAM mini-Boards
  80486 CPU Board
  Edison CPU Board
  Mini Buffered Prototype Board
  16 Bit VGA Board
  Dazzler II Board  
  Digital PDP-11 CPU Board
  Edison II CPU Board
68030 CPU Board 
  Bus Display Board
  PDP11 CPU board
  V2 PDP11 CPU Board
  PDP11 Support Board
  MEGA 328-2560 CPU Board
  FPGA Board
  SERCON Board
  V1 FPGA Board Examples
  V2 FPGA Board
  V2 FPGA Board Examples
  FPGA Z80 SBC
FPGA 80286 SBC
  FPGA Disk Controller Board 
  V4 Dual IDE/CF Card Board
  AMD 9511 Math Board  
  SUPER IO Board  
  Raspberry Pi CPU Board  
  SUPER IO Board II  
  RAM+ROM II BOARD
  Z180 S100 Bus SBC
  3P+2S IO Board 
  FPGA 80486 SBC
  FPGA_VGA_LCD Board
  12 Slot S100 Bus Motherboard
  IDE-2CF+SD Card Board
  Dual SD Card Board
  S100 Computers Front Panel Board
  Z80 V3 Master CPU Board
    

Order Form for S100 Computers Boards. 
 When a new board is announced at  https://groups.google.com/g/s100computers you can get one by filling in this e-mail "order form" below.
New boards typical take 3-4 weeks to arrive.  Payment for boards is via PayPal after you receive your board(s). 
The price will be announced in the Google Groups posting for each board. 
This form is to be used only for new boards. For old boards see below.
Please take care to enter your exact name and shipping address.       
Name:   
E-mail:  
Name of S100 Board  
Number of Boards      

Name & Exact Shipping Address:-



Reorder Of Past S100Computers Boards
I must stress however this is a hobby based group of people (spread actually around the world these days). There is no central organization or person “in charge”.  I and a few others design and produce new S100 boards (at our own expense) and when done, typically do a “group purchase” of a new board.  These are bare boards which must then be stocked with chips etc.  Typically I provide basic build/testing instructions and if needed, basic software.   The major ones are listed in the table above.   In many cases updated versions of the boards were/are being made.  

It is unfortunately a bit difficult for new people to get started since many by now already have their basic starting boards.   However from time to time a new “run” of an old board is done.  This needs somebody to organize and arrange a run.  It is more trouble than you might think to organize.  The boards are usually made by a (Chinese) company call PCBcart.com or more recently JLCPCB.com  for us.   The required board fabrication Gerber files are available at the bottom of each board’s description on this site.  From time to time a "board run" is proposed by a member.  Later when you are more experienced, you could start one yourself.   About every 6 months I announce a general "backorders" run of most S100Computers S100 boards.  It will be announced here
    
https://groups.google.com/forum/?fromgroups#!forum/s100computers
 
Ordering Older S100 Boards
Todd Goodman maintains a stock of some of our most popular boards.
They are listed here (along with a number of other "ReteroBrew Computer" boards). 
Please see:-

https://wiki.bonedaddy.net/doku.php?id=boardinventory

Alternatively you can get started quickly by scanning eBay for S100 bus motherboards, computer systems or S100 bus boards themselves. 
Here is a good place to start:-
 http://www.ebay.com/sch/items/_W0QQ_sopZ10?_nkw=s100&_sacat=11189&_trksid=p3286.m270.l1313&_odkw=s-100&_osacat=11189
NEW USERS
 To help new users here are some suggested S100 Bus setups:-

 Beginner: 
Z80 SBC or the Z180 SBC
 
Starter Z80/CPM system:
Z80 CPU Board + Console IO Board + Duel IDE/CF Board + 16MB RAM+ SMB

Starter Z80/CPM system II:
V3 Z80 80 CPU Board + Console IO Board  +  Duel IDE/CF Board + 16MB RAM 
 
Better Z80/CPM system:-
Add  ZFDC Board + Serial IO board
 
Basic 8086/MSDOS system:
Add 8086 Board + MSDOS Support board
 
Better MSDOS system:
Add Baby 80486 + VGA (16 bit) Board.
 
Sophisticated MSDOS system:
Add Full Size 80486 + OTT 32/64 MB RAM
 
Other popular boards:
68030K CPU Board, Dazzler II Board, RAM+ROM Board, Parallel Ports Board, PIC/RTC Board, 80286, 80386.
  

 Note to Beginners.
Please note that building an S100 Bus computer system using these boards is not for beginners in electronics. While the build instructions for each board may look simple,  getting them to run correctly is an S100 Bus computer setup is difficult for anybody with little electronics experience.  Because of the time required to build and test new boards I will have no time to help you debug your board/setup.  Please keep this in mind if you order a board.  For beginners I highly recommend they start with something like a Arduino, Propeller or Raspberry computer system. Also, please keep in mind many of the S100Computers boards require a ROM/GAL programmer. Most of the newer more complex boards also require a CPLD programmer or a  FPGA programmer as well.

Remember this is a true hobby/non-profit operation!  Support is limited.




MY OWN S-100 SYSTEM
By way of showing the evolution of these boards, I will describe my own S-100 IEEE-969 system.  This is a completely "homebrew system". Originally built in the early 1980's utilizing many of the S-100 boards of that era.  As I add new S-100 boards, I will go into some detail in an effort to help others build similar systems or allow them revive S-100 systems they may have stored away or have recently acquired. 

While none of this is rocket science, it does require some degree of electronic knowledge, familiarity with the S-100 bus and for the software, a working knowledge of CP/M, CP/M86 and MS-DOS (Programs, BIOS & Drivers) .  If you wish to become more informed about the S-100 bus itself try and get your hands of the book "Interfacing to the S-100/IEEE696 Microprocessors" by Sol Libes & Mark Garetz.  This book is commonly regarded as the "bible" for this field.

This will be a long term "work in progress" report. The index table above will direct you to new S-100 boards built or being tested.   See each boards section for more details.

Readers such as yourself are encouraged to participate by joining the S100Computers Google Groups forum. 

Here was my starting point for a S-100 system built with boards from the 80's. With this as a basis over time, we will swap out many of these boards into new more exciting and efficient boards using more modern IC's.

MY SYSTEM IN 2009
 My Box With Arrows

MY SYSTEM 2011
My System Arrows2

 MY SYSTEM 2013
My System 2013


MY SYSTEM 2014
 
  My System 2014
My S-100 System (As of April 2014)

  
 MY SYSTEM 2016
  
  My System 2016 
 

MY SYSTEM 2026
 A lot of boards have been added/changed since 2016. I now have multiple S100 Boxes. Below is my "final" Box setup, where I place my commonly
use "working" boards. I switched over from the above "Homemade" box to the Parastream IMSAI box with its new power supply.
   
  My System 2026


Getting Started in KiCAD.
All our boards are designed using KiCAD.  This is an open-source software tool for the creation of electronic schematic diagrams and PCB artwork. This is a fairly complex program to learn and will typically need weeks of practice to build up a board.  After the board circuit is generated with KiCAD it must then have all the chips arranged on the board and connected with 100's if not over a 1000 traces and vias.   This is done with another program called Freerouter.  Finally the resulting Freerouter files must be converted to Gerber files for the factory to actually fabricated the board.    For most of our boards I provide the most recent Gerber & Drill files to have a board fabricated. You may use these files -- at your own risk -- to have any board on this site made for non-commercial use.

KiCAD.
KiCAD is an open-source software tool for the creation of electronic schematic diagrams and PCB artwork. Beneath its singular surface, KiCAD incorporates an elegant ensemble of the following standalone software tools:-

    KiCAD project manager
    EESchema schematic editor
    CVpcb footprint selector
    PCBnew circuit board layout editor
    GerbView Gerber viewer
    Bitmap2Component component maker

KiCAD can be considered mature enough to be used for the successful development and maintenance of complex electronic boards. KiCAD does not present any board-size limitation and it can easily handle up to 16 copper layers and up to 12 technical layers. KiCAD can create all the files necessary for building printed boards, Gerber files for photo-plotters, drilling files, component location files and a lot more.

Despite its similarities with other PCB software tools, KiCAD is characterized by an interesting work-flow in which schematic components and footprints are actually two separate entities. This is often the subject of discussion on Internet forums.

The KiCAD work-flow is comprised of two main tasks: making the schematic and laying out the board. Both a components library and a footprints library are necessary for these two tasks. KiCAD has plenty of both. Just in case that is not enough, KiCAD also has the tools necessary to make new ones.
     
  KiCad Diagram
   
The main KiCAD web site can be seen here. From there you can obtain excellent instructions, videos and examples as to how to lay out printed circuit boards.  However be aware to layout complex printed circuit boards like we have here needs many hours of experience and should not be taken on lightly. 

To get started please review the following files:-
Getting_Started_in_KiCad.pdf
cvpcb.pdf
eeschema.pdf
KiCad.pdf
pcbnew.pdf
gerbview.pdf

Please note, in Dec 2015 a newer version of KiCAD has been placed in the public domain.  Unfortunately some of the files for the previous version of KiCAD (the above 2013 version) are no longer compatible with this newer version. They can be converted, but for now I will stick with the 2013 format. All our current files should work with that version.  The 2013 KiCAD version is way more than adequate for all our needs.

      
  Ki CAD buttons 
    
Initially you use the eeschema button to draw your schematic.  This is by far the most time consuming and hardest part of the program.  As I said above it takes many long hours to master this part.   You then need to convert this schematic to an actual board layout with all the IC's etc. physically in place.  

From your schematic you make a .net file

You then call in the second program cvpcb that uses the .net file to assign each IC in your schematic an actual board "footprint".  Most common footprints are already available as .mod files that come with the many KICAD "libraries".  Cvpcb generates a .cmp with all the boards components footprints.

You then use the program pcbnew to do the actual board layout. It utilizes all the .net and .cmp file data to layout your board. All the traces are shown initially as lines connecting IC pins to IC pins. Pcbnew generates a board layout file with a  .kicad_brd extension.  (Note older version of KiCAD used a .brd file extension. This is no longer supported).

Also included (see bottom of this page) is a collection of S100 footprint files specific for our S100 boards.  Make sure when you setup KiCAD that these files are on the default file search paths for these programs.  (Set Preferences, Library, User defined search path....  for eeschema, cvpcb and pcbnew).

For small simple boards you can move/edit etc. these lines by hand.  For complex S100 boards like we have here however, it is really necessary to use a trace layout program called Freerouter.  The windows .exe program can be downloaded from here.  It is completely self contained and should run in any folder on your system. 

You feed it a .dsn file (generated with pcbnew using the file menu "Export" command).  It returns a .ses file which is reaccepted by pcbnew.  See the above diagram. Rout optimization for complex S100 boards like these is a slow process. Complex boards can takes days.  You can watch the number of "vias" decrease, and the overall length of all the boards traces decrease over time.  When you see no further improvement its time to stop.   The critical file we want in the end is the pcbnew generated .kicad_brd file with the optimized board traces supplied by freerouter. That file is then used by the pcbnew "Plot" command to generate the boards "Gerber files". These files are required by board manufactures to fabricate your board.

KiCAD comes with a large selection of library footprints.
If you need a specilized chip footprint there are a couple really useful tools for quickly creating schematic libraries and PCB modules (footprints) here:-
http://kicad.rohrbacher.net/quicklib.php
http://kicad.rohrbacher.net/quickmod.php

This site (at the bottom of each boards description page) has the required .kicad_brd file you need to generate the Gerber and drill hole files for the manufacturing of all S100Computers boards.

Using S100Computer KiCAD files
All S100computers S100 boards now have a Gerber .zip file at the bottom of each boards page. If you wish to use these files for your own run its easiest if you use only this .zip file.    If you do your own layout, I suggest the following approach:-

When you “Plot” the files in KiCAD place them in an empty/new sub-folder (Gerber).  Then go to that folder and combine them all into one .zip file.  This is the file you send to the board manufacture.  In that folder the should be a total of 12 files including the zip file.  Always, no exception.  If less, go back to the “plot” dialog and find out what file is missing.  (This assumes you will not have a silkscreen on the back of the board).
 
One quirk of freerouter is that sometimes it places vias between the gold edge connectors.  I largely mitigate this by placing a protected/keep-out area on the bottom ¼ of the connectors.  See this picture:-
  
  S100 Connector-Freerouter
   
It must be less than half the height of the connector pads.  Even then,  after the board is resolved, occasionally you will have to hand tweak some vias by moving them upwards.  I also like to when possible, avoid traces running near the tops of the gold pads by pushing them up. 

While on this, in general before I send a board to freerouter I hand lay down some wide major power lines.  When a board is done I tweak things like moving around an Vcc traces that are on 3 sides of a pad/via away slightly. Highlighting the Vcc traces and running extra traces (if possible) to the power pins of the major power hungry chips like a 1508 CPLD.   This often requires shifting freerouter traces and using multiple vias.  So in many case the final Gerber file will NOT be the same as the original Freerouter/KiCAD "Plot" files.
 
Finally before you save the Gerber plot files be sure to do a “design check”.  On a few occasions, (~3 times for probably 1000 runs), freerouter had a via too close to a trace.
 
So if you wish to use these S100Computers files for your own run, use only the .zip Gerber file at the bottom of each boards page.  If you “roll your own”  you need to go through the above steps.  The .zip files are all you need to send to most board fabricators.  A summary of the major KiCAD commands can be obtained here.

Lastly one trick, before you import the freerouter .ses file back into KiCAD save the .kicad_pcb file with another name such as xxx(no traces).kicad_pcb.  That way if you wish to modify the board you will not have to remove all the freerouter traces (KiCAD removes your own hand drawn traces as well).

S100 Board Manufactures.
 Almost any printed circuit board manufacture can fabricate these relatively simple two sided printed circuit boards. Issues are cost, time and what their setup/minimum order is. Highly recommended for production boards (with gold plated fingers etc.) is JLCPCB Circuits Prototype Boards site. They are very cost effective and have an amazing fast turn around time and quality considering they are in Hong Kong (a few days).  In the US  Advanced Circuits for prototype boards (no gold etc.) is an option. They are more expensive but reliable with good quality work.  In the past I also used PCBCart in China also with good results but slower delivery. 
      
  PCB MSG New 
     
Here is a interesting video showing how PC boards like ours are made. (From YouTube link).
 


Parts Lists.
Most of the boards on this site use common 74LSxx style chips.  If you are going to build a number of S100 boards (or repair them),  you really should build up a stash of these chips.  I get most of my components from Jameco, Mouser, Anchor-Electronics, Unicorn Electronics or for discontinued chips UTSource, and in that order.  I use Jameco for all the support stuff, sockets, jumpers etc.    I wish I had time to write-up a detailed BOM for each board, fortunately Richard Chin and Rick Bingham have done so for some boards - thanks Richard & Rick.  If you want to contribute please send one on to me.

KiCAD Download           (Note this is a large file, 197MB).
KiCAD Footprints etc.     (Note this is a large file, 17MB).
KiCAD Documentation    (8MG file)

Freerouter Download
KiCAD Commands Summary
JLCPCB Circuits Prototype Boards site
Advanced Circuits Prototype Boards site
PCB Cart Commercial Boards site

This page was last modified on 02/28/2026