Subject: Re: full duplex ethernet trouble
To: Charles M. Hannum <>
From: David Laight <>
List: tech-userlevel
Date: 07/19/2004 07:52:33
> It's not really debatable.  We implemented "auto-advertisement" in two 
> different projects I worked on, and complaints about duplex mismatches and 
> whatnot effectively disappeared.

I presume you mean that you 'force' the configuration by setting the
ANAR registers to only allow the option you want?

I did that once - in order to stop FDX being negotiated since I had no
way of detecting the result of the negotiation (and it was a pcmcia card).

One slight difficulty is that the ANAR register doesn't (usually) affect
autodetect - so a 10M or 100M (single speed) hub will always connect.
So if you've set the ANAR to 100M FDX, and plug into a 10M hub the link
will come up.....


David Laight: