On Aug 19, 12:10, Mike Ford wrote:
> Subject: Digital kinda ethernet card?
> I noticed my friends AlphaServer 2100 has the same card poking out the
back
> as one of the cards in my neatly sorted pile of old ethernet cards. The
> card is ISA and the back looks as follows from bottom to top, RJ45, fat
> LED, DB15 with a screw post on each end, fat LED. Is this a ethernet
card?
Almost certainly. The RJ45 will be 10baseT and the DA15 will be an AUI
connector (sometimes called 10base5 because they'd often be connected by a
drop cable to a thick wire transceiver, but in fact you could connect a
10base2 or 10baseT transceiver instead). There may be links to set which
is the active port, though modern cards sometimes do that under software
control, or autodetect a live link on the 10baseT when they power up.
The AUI connector usually has a clip mechanism rather than screwposts,
though. An ordinary miniature transceiver won't fit onto the screwposts.
The only other cards you're likely to see that are similar, is a few old
ISDN cards. They have an RJ45 for the S-bus (ISDN) connection, and one
make did use DA15 for a serial port, but they always had one more modular
jack (or 600-series jack) for a phone, too. They usually have a large
(2-3" x 3-4") covered section with the telecomms section isolated inside
it. Ethernet cards usually have a much smaller (1" square or so)
monolithic voltage converter/isolator to generate the isolated 10V supply
for the network driver.
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
Received on Thu Aug 19 1999 - 17:25:54 BST