View Full Version : A new S100 Bus 80386 CPU Board

December 21st, 2015, 03:25 PM
Im delighted to announce 3 new boards from S100Computers.com

The main board is a new V2 CPLD based 80386 master/Slave CPU board. As many of you know this board has been a long time in coming. While relatively simple on the surface when you get down to it there were a number of frustrating issues. Im very happy with the final product however. It uses a common AMT-1508 CPLD to translate all the 80386 signals into the corresponding s100 bus signals. The CPU can address two RAM areas. The lower 16MB of addressable S100 bus RAM (at 7-8MHz) and all RAM above this (in Protected Mode) at 14-16MHz. To address the latter a ribbon cable bus connector which I call the S100-OTT bus for Over the top is used. This is a 32 wide data, 4GB capacity bus.

The CPU is controlled by the 80386 Monitor in Real and Protected modes. The board can boot MSDOS V4.01 directly using our MSDOS Support board. All the main S100 bus signals are programmable.
The second board is a S100-OTT 32 or 64MB Static RAM (32 bit wide) board to be used with this board in Protected Mode.
The Third board is a new version of our 16MB S100 bus Static RAM (8 or 16 bit wide) board. This one has a number of improvements over the earlier boards.

To get started please see here for information about the V2 80386 board.

As has been the case in the past I will order a batch of each of these bare boards for S100 bus users. Please note the 80386 board is quite a complex board. I have written up some detail instructions in building and debugging it. That said it is not a beginners board.

Batch orders for boards like this go out rarely. If you think you would like to take a go at a board in the future you might want to get it now. The price of each board (depending on numbers) is between $12-$14 per board + shipping costs.

Two things.
1. Do not send money at this stage. I will send a bill with the board(s) themselves.
2. Please order the board only on the S100Computers Google Forum


This way the chance of your order getting lost is less. I will publish a total list before sending the order out just to be safe. It will take at least a month before you receive your board(s). They are fabricated in China by PCBCart.


December 22nd, 2015, 06:48 AM
Great work, John!

December 22nd, 2015, 07:22 AM
While relatively simple on the surface when you get down to it there were a number of frustrating issues.
... and the old chaos remains with much much more issues. :roll:
Shame on you John! :picture:

December 22nd, 2015, 08:57 AM
The shame is on you, Micro, for complaining about a completely non-commercial site which works fine, has tons of information, no ad rubbish, and is something I for one enjoy visiting much more than 90% of the javascript-infected, bling-focused commercial sites out there. We have been through that in the other thread. Leave it, please.