Re: tulip.c and 21140-AC chip

Donald Becker (becker@cesdis1.gsfc.nasa.gov)
Tue, 19 Nov 1996 18:14:33 -0500 (EST)


On 19 Nov 1996, Goran Thyni wrote:

> I checked out the driver, and saw some stubs for the 21142 chip.
> Is this work in progress?

Yes -- it appears that the 21142 is a 21140a with the "SYM" (non-MII)
support removed. The SYM symbol-generation support was needed before
MII transceivers were available, so that the 21140 could use the then-new
copper-FDDI line drivers that made 100baseTx possible. Now the physical
symbol generation is done in the transceiver.

I didn't know that the 21142 was available yet.

> I have a card of this type and willing to assist if that the case.
>
> Quick and dirty patch to get though to prompt (line 673):
>
> ! for (i = infoleaf->count; i; i--) {
> ------
> ! for (i = infoleaf->count; i > 0; i--) {

I don't think this is patch is necessary for the 21140 (I put it in anyway,
since it's a "free" way to avoid a some crashes from a bad SROM), but the
'42 has a different SROM format for the "infoleaf".

Are you interested in looking at the Digital documentation on the
SROM/EEPROM format? (I'm out of town right now, and won't be able to look
at it until next week.)

Donald Becker becker@cesdis.gsfc.nasa.gov
USRA-CESDIS, Center of Excellence in Space Data and Information Sciences.
Code 930.5, Goddard Space Flight Center, Greenbelt, MD. 20771
301-286-0882 http://cesdis.gsfc.nasa.gov/pub/people/becker/whoiam.html