[3c509] N-Way Auto Negotiation and Full Duplex

Wm. G. McGrath wgm@telus.net
Mon Sep 16 20:37:01 2002


Hi all,

I am slowly solving the puzzle of full duplex with the 509B, and
have managed to get the card to boot in full duplex mode after
compiling the latest version of the driver (1.18c) and installing,
and configuring it appropriately. Here's the output from boot:

>eth0: 3c5x9 at 0x300, 10baseT port, address  00 60 97 55 4a a1, IRQ
>5. 3c509.c:1.18c 1Mar2002 becker@scyld.com
>http://www.scyld.com/network/3c509.html

>eth0: Forcing 3c5x9b full-duplex mode if_port: 12, sw_info: bf31
>eth0: Setting Rx mode to 1 addresses.

Now it seems I am up against ethernet history. I am told that 509B
full duplexing was developed prior to N-Way Autonegotiation. So my
switch, a D-Link DSS-8+, does not recognize the 509B as full duplex
capable and seems to connect in half-duplex mode - that is the full
duplex indicator led doesn't light. The card works but I'm not sure
what mode it is in really. If I go by the boot messages the card is
in full duplex mode. If I rely on the switch indicator it's in half
duplex mode. Here's what the manual says:

>The "Full-Duplex/Collision" LED indicator depends upon LAN card
>capabilities for full duplex or half duplex. 
>If the attached device does not support auto-negotiation or has
>auto-negotiation disabled, an auto sensing process is initiated to
>select the speed and set the duplex mode to half-duplex.
>(Pretty clear huh. :/)

So I have two questions really. One, how can I test the link and see
what mode it's in or what kind of speed I'm getting. 

But more importantly, is there a work around. Can I manually set a
parameter to activate nway autonegotiation? Is there some way to
modify the driver to autonegotiate with the switch?

Does anyone know anything about old time full duplex and N-Way 
autonegotiation?

	bill