[3c509] Question about Half-Duplex negotiation

Donald Becker becker@scyld.com
Thu Jan 10 17:53:45 2002

On Thu, 10 Jan 2002, Bill Cattey wrote:

> To: 3c509@scyld.com
> Subject: [3c509] Question about Half-Duplex negotiation

Note that this is the 3c509 list, for the ISA '509 card.
You want the 'vortex' list, for the PCI cards.

I've Cc:ed this to the vortex list.

> Eventually we traced the problem to the fact that the machine
> had somehow came through the autonegotiation with our subnet
> to attempt to speak half-duplex to our full duplex port.

The typical problem is that the switch port is forced to full duplex.

> (The way I determined this was to have our network operations folks look
> at what I was doing and then use mii-diag to force full duplex, and
> watch that make the problem go away.  Interestingly testing two other
> identical
> GX150's on the same subnet turned up one working fine, and another one
> that had problems till we told it BE full duplex.)
> The driver I'm running is:
> 3c59x: Donald Becker and others. www.scyld.com/network/vortex.html
> 02:0c.0: 3Com PCI 3c905C Tornado at 0xec80. Vers LK1.1.16
> (Mind you, the next line in dmesg output said:
>   ***WARNING*** No MII transceivers found!

That's a bad message -- there could be a timing issue at work here.

Try the alternate 3c59x.c driver updates at

> bash-2.04# ./vortex-diag -a -v
> vortex-diag.c:v2.05 5/15/2001 Donald Becker (becker@scyld.com)
>  http://www.scyld.com/diag/index.html
> Index #1: Found a 3c905C Tornado 100baseTx adapter at 0xec80.
> Saved EEPROM settings of a 3Com Vortex/Boomerang:
>  3Com Node Address 00:06:5B:47:D0:78 (used as a unique ID only).
>  OEM Station address 00:06:5B:47:D0:78 (used as the ethernet address).
>  Manufacture date (MM/DD/YYYY) 6/10/2000, division , product .

Hmmm, this appears to be a rather old card -- produced just about the
time when the first "Cx" chip was released.

>  MII PHY found at address 1, status 0024.
>  MII PHY found at address 2, status 0024.
>  MII PHY found at address 3, status 0024.
>  MII PHY found at address 4, status 0024.

It really does appear to be an early "Cx" board, with bogus transceiver
responses.  Using an updated driver should work around the problem.

Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Second Generation Beowulf Clusters
Annapolis MD 21403			410-990-9993