A while ago I found a mention of the 12665 at Jeff Moffat's site.
To quote a quote from there:
"The kit provides for communications between two computers over
long distances in a heavy industrial noise environment."
Go to:
http://oscar.taurus.com/~jeff/2100/iocards/iocards2.txt
and do a text search for 12665. According to the above it's the PCA
in interface kit type 12771. (Going up a level in the URL provides
an email address to get the manual.)
Perhaps (I'm speculating) it's RS-422/3 instead of RS-232.
(I've been compiling a list of HP 21 I/O interfaces with cross-refs
to web sources. I hope to put it up on the web 'real soon now'.)
Philipp Hachtmann wrote:
Hi folks,
does anybody know anything about this HP1000,21MX etc. card:
Part No. 12665-60011, labeled "serial interface"
I did not find any suitable information on bitsavers and don't know
where to look. If anybody knows that card...
Perhaps it is the standard serial interface/tty interface?
Please help....
Thanks,
Philipp