[net.news] The satellite buffer board -- ideas are welcome...

lauren@vortex.UUCP (Lauren Weinstein) (12/17/84)

I've gotten a lot of messages from people asking how they can
help with the project.  I can mention one place right now where
detailed technical suggestions can be of use--the design
issues of the message buffering board.  While the demod/decoder
(the pair that will hopefully be available as a set for $500)
have to meet all sorts of protocol, video, and cable standards,
we are under no such constraints for the add-on buffering board
that would sit between the decoder and the "mainframe" computers
receiving articles.

This board will need to take serial ASCII, at speeds varying
(probably) between 1200 and 9600 bps over time, extract and
store as many messages as possible (as selected by mainframe
commands regarding catagories, sequence numbers, etc.) and make
them available to the mainframe in a solid, flow-controlled
manner.  This board would contain as much memory as reasonably
affordable, and the more sophistication that can be built onto
the board and its firmware, the better.  This board will also
be responsible for error correction (through merging of multiple
message transmissions), keeping track of received and needed
message sequence numbers, and a host of other functions that are
best handled outside people's mainframe systems.

The practical limit on memory for the board will probably 
relate to money.  As I've mentioned before, I'd sure like
to see this board cost no more $150 to $200 (including memory,
manufacturing and distribution costs, etc.) if possible.  Of course,
ideally, it would also be subject to the same sort of buyback
and rental arrangements that (I'm hoping) would eventually 
be available for the demod/decoder.

The firmware for this board could get quite complicated quite 
quickly, and I KNOW that I will NOT have the time (nor the
inclination, to be frank) to do that coding.  The satellite carrier
may be able to contribute to the board's design and manufacturing,
since they could apparently get considerable use of their own
out of such a device, particularly if it were fully addressible
and had some TV display capabilities of its own.  Their participation
may well serve to help keep the price down since it might mean
higher volume demand for the equipment.

In any case, I will probably be talking to them about the board
issues in early January, and I'd appreciate specific technical
suggestions (memory, CPU, etc.) that people out there could
make that I could bring to the table for those discussions.
Please only tell me about components you've worked with yourself
rather than relay second-hand info if possible.  Your suggestions
regarding memory and related components for the buffering board could be
of great use if the project is to proceed beyond the experimental stage.

By the way, another place where assistance will be needed down 
the line will be in the design of the mainframe software to
interface the board (and thus the demod/decoder) to the Usenet
software running on the mainframes.  This may well be a substantial
task in itself, since it will involve sending out specialized
uucp messages to the stargate for message retransmissions in some
cases and involves a number of other unique aspects as well.
Please don't volunteer for the mainframe software effort yet--it's still
too early for that...

All replies regarding the buffering board hardware design should be 
sent to me as uucp mail, not posted to this group.  Thanks again.

--Lauren--