From: becker@super.org (Donald J. Becker) Subject: Re: 3c501 cards Date: Mon, 14 Dec 1992 18:41:34 GMT
In article <724336546.AA26409@remote.halcyon.com> Jim.Corbett@f35.n152.z1.fidonet.org (Jim Corbett) writes:
> > I have recently come into a rather large quantity of
> > 3c501 cards
> > (~30). I would be happy to sell them for $20 plus
> > shipping. Buy 5 or
> > more and get a discount! I realize that currently the
> > 3c501 drivers
> > haven't been released even in alpha yet, but I have
> > been given to
> > understand that they are in progress.
>
>I am not familur with that card, what is it, 8 bit, 16 bit?
>
> * Origin: Intermittent Connection, Eugene OR 503-344-9838 (1:152/35)
>
It's a first generation 8 bit ethernet card using the SEEQ 8001 chip.
I would not recommend using a 3c501 for several reasons:
The 3c501 is far too braindamaged to use. It can only do one thing
at a time -- while you are removing one packet from the single-packet
buffer it cannot receive another packet, nor can it receive a
packet while are loading a transmit packet. This was fine for
a network between two 8088-based computers where processing a packet
took 10's of msecs. (10Mb/sec was faster than the IBM-PC bus!)
but in an environment where machines are expected to send and
receive streams of back-to-back packets the 3c501 just cannot
function.
If he is referring to my pre-alpha 3c501 driver -- it's not finished,
its low on my list of priorities, and I'll never release it
beyond alpha when I do finish it because of the performance problems.
Documentation on the 3c501 is a problem. 3Com no longer prints the
3c501 documentation. They have a limited number of old copies, but
even those have a warning on the front that they (3Com) didn't have
their usual technical documentation on the board.
-- Donald Becker becker@super.org Supercomputing Research Center 17100 Science Drive, Bowie MD 21114 301-805-7482