Subject: Re: 3COM ethernet controllers
To: Mark Randelhoff <>
From: Frank van der Linden <>
List: tech-net
Date: 04/19/2001 15:04:56
On Thu, Apr 19, 2001 at 02:33:57PM +0200, Mark Randelhoff wrote:
> I would really appreciate some information about the difference between the
> 3COM 3c905a-TX and 3com3c905b and c -TX's.
> I am running 1.4.1 on and i386, and the 3c905a works OK but the b and c's do
> not.... I know that 1.5 supports the 3c905c-TX.
> What changed in the implementation of the driver between 1.4.1 and 1.5?
> Why was this necessary?
> Was this a result of a change in the hardware implemention or for
> performance?
> How simple would it be to include this functionality in 1.4.1?

The 3c905 cards before the 'B' revision contained both the old
PIO (programmed I/O) interface and the more efficient DMA interface.
The 'ep' supports used the PIO interface, but not the DMA interface
(and as such it also supports some older cards).
The 'ep' driver is included in 1.4.x.

The 3c905 cards revision 'B' and above, only have the DMA interface.
So, the 'ep' driver could not support them. The 'ex' driver was
written to support the DMA interface.

Coming back to the point, the 'ex' driver is included in 1.4.x,
and the 905C is recognized since 1.4.2. The easiest thing to
do for you is to just use an 1.4.2 kernel.

- Frank

Frank van der Linden                 
Quality NetBSD CDs, Support & Service.