New LinkSys CardBus vs. Old LinkSys CardBus

Nathan Anderson
Wed Dec 23 20:56:29 1998

Hey Donald!  Thanks for taking the time to personally respond to my

Donald Becker wrote:
> > not.  The other strange thing about this card is that the tulip driver
> > is not extracting the correct MAC address from this card.  The address
> > is always shown to be 00:80:00:80:00:80.
> This is the 'TD' card, with a larger EEPROM.
> I don't have one to test with, but please try the following change to line
> 391:
> -#define EEPROM_ADDRLEN 6
> +#define EEPROM_ADDRLEN 8
> This should allow the driver to work, but only with the 'TD' card!
> Please send a report.
> If this works correctly, I can change the driver to use the chip revision
> number to select the EEPROM_ADDRLEN value.

Well, here's my official report. ;-)

It kind-of works now.  At least the MAC is read correctly now.  The card
still doesn't work, however.  After the driver is loaded and a link is
established, about two seconds later I still get a "transmitter stopped"
on this card.  (That is, on the TD card even with the dongle connected
and a link from the dongle to the hub in place, I still get "transmitter
stopped".)  Still same CSR5 and CSR6.

Also, my new startup messages with the TD card:

kernel: tulip.c:v0.90f 12/17/98 
kernel: eth0: Digital DS21143 Tulip at 0x280, 00 e0 98 04 33 ab, IRQ 3. 
kernel: eth0:  EEPROM default media type Autosense. 
kernel: eth0:  Index #0 - Media MII (#11) described by a 21142 MII PHY
(3) block. 
kernel: eth0: ***WARNING***: No MII transceiver found! 

???  No MII transceiver found?  Is that fatal?

Also, about my original question: which card would be the better one to
keep and use?  I'm leaning toward the first card right now as it
actually seems to work [;-)].

Also, would you be so kind as to (briefly; I don't wish to take up your
time -- if it can't be done briefly then forget it :-)) describe what an
MII transceiver is?  I'm trying to understand the differences between
the tulip cards that do have transceivers and those that don't.  Is it
reasonable to assume that, based on the messages and diagnostics I've
done so far on both cards, that the first card has an MII transceiver
while the TD-based card doesn't?

Perhaps if you could just point me in the direction of a FAQ or
something, that would be the best thing. :-)

> >  With the special PCMCIA-revision of 0.89
> > (0.89L), the lights act normally and the card appears to work okay
> !! I'll check that out.  The drivers should behave identically.

That's what I thought.

Note that it is only with the older card that the 0.90 and above drivers
behave like this.  The lights on the newer TD-based card I have work
with either revision of your driver.
> > The final weird problem I am experiencing with this card is that /unless
> > the dongle is connected to the card/, I get:
> > eth0: The transmitter stopped!  CSR5 is f0068002, CSR6 b3860002.
> Yes.  The dongle appears to contain some vital circuitry that must exist
> when the card is powered up.  If the dongle isn't plugged in, the MII
> transceiver isn't detected.  Since the EEPROM on many cards is wrong, the
> driver relies on detecting the MII transceiver to switch into MII mode.
> A driver designed to work only with the LinkSys card will not have this
> problem, since it just "knows" the transceiver connection is MII and ignore
> the incorrect EEPROM table.

Ah, I that's why the Windows drivers that come with the card
don't fuss when the dongle isn't connected.

> > The problem that is common to both cards is that both of them
> > occasionally (and randomly) lock up the machine.  Hard.  One time (and
> > only once) was a message displayed on the console before a lockup.  I
> > have not seen it happen since on subsequent lockups.  The message said,
> > "Unknown interrupt."
> This is likely a hardware or CardBus controller setup issue.
> Does it happen with other OSes?

The thought had occurred to me.  It does not happen under other s/w
platforms (only other one tested is Win95 though ;-)).  I just wanted to
know whether you or anyone else had experienced lockups with this card
and your driver.

> > It's interesting because the
> > Windows driver disk that came with the newer (second) card I just got
> > works with both cards, but the older Windows drivers only work with the
> > first card.
> It's much easier to write a backwards-compatible driver than one that
> predicts future hardware changes ;->.

Haha. ;-)  Of course. ;-)  I was just surprised that the differences
between the two cards could be so diverse as to require a change in the
driver, that's all.

Thanks again,

-- Nathan Anderson    16 yrs old