9 Oct
2009
9 Oct
'09
1:38 p.m.
On Fri, Oct 9, 2009 at 3:42 PM, Chuck Guzis <cclist at sydex.com> wrote:
On 9 Oct 2009 at 14:14, Ethan Dicks wrote:
Maybe a DUP-11? IIRC, that's one of DECs comm adapters with a
COM5025. It's just a serial chip with a bus interface - no smarts at
all. All of the protocol implementation would be thrust on your box.
In our experience, there were certain protocol implementation details
that different vendors completed to varying degrees of success.
I think one list member ever has piped up that
they found a COMBOARD
in a rescued system...
That brings back a bunch of ugly memories. ?Back around 1983, we had
an 11/750 on lease running BSD and a leased 9600 bps line (Bell 208
modem). ?The dealer who supplied the system did so with the assurance
that he could provide bisync/HASP support on BSD. ?I don't recall
what the board was in the 750, but I seem to remember it was
something like a DU-11 (it's been far too long). ?The vendor brought
in everyone he could hire to fix it and eventually gave up. ?At $5K
per month for a leased line sitting idle, we were none too happy.
COMBOARDs were available for 4.0BSD and 4.1BSD (it's where I cut my
teeth on UNIX), but since we delivered a hardware-software solution,
we couldn't come close to approaching the price of a
DEC-card-and-software solution. OTOH, our stuff _did_ work and did
work efficiently, so we did occasionally get a sale to someone who
tried stuffing a DUP-11 or DUV11 into their box and was unhappy about
a host-driven solution, but with the higher up-front cost,
I think we eventually ended up using an IBM PC-XT with
a sync adapter
to do the job.
Some people went that route in the 1980s, but our customer base, at
least, wanted to move largish files and wanted a certain amount of
robustness that a desktop machine didn't offer, and were willing to
pay more than the cost of a dedicated PC to do it.
-ethan