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View Full Version : Group Effort S-100 Prototype Board



monahan_z
September 13th, 2009, 11:48 AM
I have made a number of very useful point to point wire soldered S-100
boards over the years which I would now like to get down on a printed
circuit format (and increase my bus speed). Things like a slave 286,
an IBM Keyboard to ASCII parallel port adaptor (Z80 driven), a S100 to
IBM-PC ISA bus converter board, a detailed diagnostic hex display
front panel board etc. There are more I intend to do such as a 80386
with static RAM, an internet board etc.

One of the real pains in doing a point to point board is the
monotonous effort needed to buffer the (24) address lines, the 16 data
lines, and the major status & control lines. A prototype PC board with
a row of buffers along the bottom would be very useful. The rest of
the board should be a simple grid or holes/solder pads since LSI chips
can vary tremendously. The Ackerman prototype board:-
See here (http://www.s100computers.com/Hardware%20Folder/Ackerman%20Digital%20Systems/Kludge%20Board/Kludge.htm)

does all this, but it is overkill with little space left on the board.
For example these days you need only one +5V Regulator.


To accommodate the varied uses I and others would have, I propose a
row of headers just above the above buffers where different daughter
boards could be attached. They press on to a row of pins on the S-100
board. Now the real advantage of this arrangement is that while the
"S100 base board" would be somewhat expensive to make with its gold
connectors etc., the adaptor boards could be quickly made by outfits
like PC-Express that charge ~$60 for 3 boards. You can test many
designs with this arrangement and everybody can do their own thing.
Done right little S100 board real estate would be lost.


My problem is I have no experience currently doing PC board
fabrication. I use Novaram's DipTrace (V1.5), free web download to do
schematics. Itís far better than anything else I have seen free on the
web, and it has a schematic to PC board layout converter but I am
inexperienced in going further (currently).


Anyway, was wondering if anybody else would be interesting in a
prototype board like this and/or could help in its production.

RickNel
October 21st, 2009, 04:14 PM
John has worked this through, together with Andrew Lynch, and is now about to get a set of these advanced powered and buffered s-100 proto boards made up. He's inviting expressions of interest from people interested in having one or more. See full layout and schematic of the card on his site www.s100computers.com.

monahan_z
October 22nd, 2009, 09:20 AM
Thanks Rick, we are joing to send out for a run of 10 boards right now unless we hear otherewise. The layout can be seen at:-
http://www.s100computers.com/Cards%20For%20Sale.htm

NobodyIsHere
November 5th, 2009, 04:07 AM
Hi! The PCBs for the www.s100computers.com & N8VEM S-100 buffered prototype board arrived last night. They look really nice. I will be sending an email to everyone who contacted me to order their own PCBs.

Thanks and have a nice day!

Andrew Lynch