21143:Asymmetric result

M.Brands shrike@il.fontys.nl
Sun Jul 11 09:32:46 1999

On Sat, Jul 10, 1999 at 10:27:04PM -0400, Donald Becker allegedly wrote:
> On Sat, 10 Jul 1999, devdrvr wrote:
> > With the 21143-TD or PD what is the right way to specify to one versus the
> > other?
> For almost all uses you shouldn't need to specify anything.  Just leave the
> setting at the default at 0, "autonegotiate/autoselect".
> The reasons for overriding the default media type:
>   Some older cards didn't have a transceiver table in the serial ROM.
>   A few current cards don't have correct tables.
>   Older switches and 21140-SYM cards can't autonegotiate full duplex.

How about cards connected by a crosslink cable? I've got two Digital
DE500BA (21143-PC chipset) connected by a 1.2 meter CAT5 cross-link
cable (IBM made). When I let them autonegotiate, they settle for
10baseT. If I force on of the cards to 10baseT-FD or 100baseTX, the
other one also switches to 10baseT or 100baseTX. However, if I force
100baseTX-FD, I get a transferrate of about 130 kbyte/sec :(

If I swap one of the cards for an Intel EEPro 100, 100baseTX-FD does
work correctly. (Doesn't matter which card.) I've used both the tulip
driver (0.91e) and the DE4x5 driver. Note that autonegotiation still
doesn't work.

I assume that the cards are dropping to 10baseT when autonegotiating is
caused by the fact that when the first machine comes up, it sees there's
no machine at the other end of the cable yet and switches to the lowest
setting (10baseT). When the other machine comes up, the link is running
at 10baseT, so it also start using 10baseT. Is this correct? (Messages
printed by the DE4x5 driver seem to support

Btw. I've used options=5 to force 100baseTX-FD...

tulip.c:v0.91e 5/27/99 becker@cesdis.gsfc.nasa.gov
eth1: Digital DS21143 Tulip rev 48 at 0xe400, 00:00:F8:09:09:93, IRQ 9.
eth1:  EEPROM default media type Autosense.
eth1:  Index #0 - Media 10baseT (#0) described by a 21142 Serial PHY (2) block.
eth1:  Index #1 - Media 10baseT-FD (#4) described by a 21142 Serial PHY (2) block.
eth1:  Index #2 - Media 100baseTx (#3) described by a 21143 SYM PHY (4) block.
eth1:  Index #3 - Media 100baseTx-FD (#5) described by a 21143 SYM PHY (4) block