Hi all
I think you're likely to be correct, Tony, about the application being
just a link adapter to something remote, except that the RS422 is at
the other end of the board from the I/O connector on what is normally
the rear panel of a PC.
I have a bare B008 PCB, but not a fully assembled one. If you would
like me to look at the bare PCB to answer any other question about the
board, please let me know
Best wishes
Paul
On 21/11/2017 10:48, tony wrote:
Hi all
The bed of nails could be used in place of a C004 for another reason –
it would need a piece of code to configure it. Replacing it with fixed
wiring saves that – as the other extra board is an RS422 driver and
the unused TRAM sockets have a link hardwired through, I would guess
that this board was used in some sort of test setup as the simplest
and cheapest way to drive some remote(ish) transputers from a PC. If
there were no TRAMs with transputers on the board, then this board
would simply have been a link adapter (can’t remember the part number)
mapped into the memory space of the PC then driving via RS422. As
such, someone may have been using it without transputers at all – just
as a means of getting a nice simple high speed serial link for some
sort of one off piece of kit. In that case, an RS422 connected to
another link adapter may have been all that was at the other end – or
they used RS422 then connected to a TRAM and so that all the
transputers were in the remote kit and this was simply a cheap way of
booting them over a reasonable distance.
They may have removed the C004 from the B008 socket and used it in
their own kit at the other end.
Tony Gore
/Aspen Enterprises Limited/email tony@xxxxxxxxxxxx
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tel +44-1278-761000 GSM +44-7768-598570 URL: www.aspen.uk.com
<http://www.aspen.uk.com/>
Registered in England and Wales no. 3055963 Reg.Office Aspen House,
Burton Row, Brent Knoll, Somerset TA9 4BW. UK
*From:*Paul Walker (4Links) [mailto:paul@xxxxxxxxxxxx]
*Sent:* 21 November 2017 08:43
*To:* Lawrence Dickson <tjoccam@xxxxxxxxxxx>; tony <tony@xxxxxxxxxxxx>
*Cc:* Øyvind Teig <oyvind.teig@xxxxxxxxxxx>; Roger Shepherd
<roger.shepherd@xxxxxxxxx>; occam-com@xxxxxxxxxx; PeterMorris
<ptr.mrrs@xxxxxxxxxx>
*Subject:* Re: Ravenscar profile and occam on the transputer
Dear Larry, Tony
The "Bed of Nails" is a C004 32-port crossbar switch whose data sheet
(including pinout) you can find at:
http://www.datasheets360.com/pdf/-5874436622983995731
Not everyone wanted a C004, and it's possible that, at the time we
designed the B008, the C004 was not in production, so the 84-pin array
was a way for users to construct their own link network without having
to bother with configuring the C004.
Lifting the pin array should not cause any damage, but I don't think
you will see very much underneath it.
Best wishes
Paul
On 20/11/2017 17:54, Lawrence Dickson wrote:
TRY AGAIN AFTER REDUCING SIZE OF ATTACHMENTS . . . sorry if some
of you get it twice . . .
Thank you, Tony! I guess RS-422 could do a link because it is
capable of 10 Mbits/second according to Wikipedia. But that still
leaves the bed of nails a mystery (what did it replace)? Peering
under the TRAM-like thing (which I am afraid to pull because it
may have some essential connection with the wire wrap on the bed
of nails) I see IMS B008 221-CRBD-302-05 dated 1990, which seems
to fit page 3 of my User Guide (also dated 1990), except for CRBD
instead of CBRD. But surely the bed of nails is not standard.
Close-ups attached.
Larry