Full Duplex Lights

B. James Phillippe bryan@terran.org
Thu Jul 22 00:47:39 1999

On Thu, 22 Jul 1999, Jason Thomas wrote:

> Mogens Kjaer [mk@crc.dk] wrote:
> > Jason Thomas wrote:
> > > 
> > > Does anyone have any idea when the state for the full duplex lights
> > > will be implemented into the tulip drivers, or if it has already been
> > I think the explanation is, that the LED's are controlled differently
> > on all tulip NIC's, so to make them work would be a big job.

The LED's are typically either wired into the PHY chip and controlled
by the hardware, or they are connected directly to the MAC chip general
purpose pins and must be enabled by programming the MAC chip with the
proper settings contained in the SROM.  Cards designed using the first
method will have working LED's before the OS has even booted.  In the
latter case, all you really need to do is parse the SROM correctly and then
set the general purpose pins to be inputs or outputs based on that
information.  I have seen failures in some versions of the tulip driver to
perform this step properly.

All that said, if the driver and tulip-diag report the controller as being
in FDX mode and you're getting the right performance figures, ignore the
LED for now.  If you're getting worse performance than normal, it's
possible that one controller is in FDX and the other is not.

# bryan at terran dot org
# http://www.terran.org/~bryan