Need boot ROM for Asus A7M266-D motherboard

Donald Becker becker at
Wed Dec 11 17:53:53 PST 2002

On Wed, 11 Dec 2002, Tom Bartol wrote:
> On Tue, 10 Dec 2002, Donald Becker wrote:
> > On Tue, 10 Dec 2002, Jack Wathey wrote:
> > > model A7M266-DL, which is just the A7M266-D bundled with a 3Com 100
> > > Mbps NIC, model PCI-L3C920.  According to 3com, the chipset on this
> > > Unfortunately, the A7M266-DL bundle does not include a boot ROM,
> > > although the NIC has a socket for one, and the manual says that one
> >
> > Get a 29 series Flash chip of the right pin count.
> > A likely part is the Atmel AT29c010 128Kx8, which was the recommended
> > part for earlier boards.
> I am assuming that this part will come as a blank ROM and that we would
> have to flash it with the appropriate boot code.


> We're pretty computer
> savvy but have never programmed or flashed our own chips.  Several
> questions now arise:
>   1) Is there a vendor that supplies these ROMs already flashed with PXE
>      boot or other suitable boot code (e.g Etherboot).

There likely is a one-person operation somewhere, but I don't know of

>   2) if not then I assume we'd have to obtain necessary hardware and
>      software to flash our own chips.

I you are running Scyld Beowulf, you already have the software that we
have written to do this -- 'vortex-diag'.
If you are running some other system, you can get the source code at

> 3) Etherboot doesn't specifically mention support for the 3C920.

It very likely works -- the 920 is just one of the 905c chip with
slightly different EEPROM programming.

> > I'm curious: those are the two main players, what was lacking?
>   Both the Tyan and Gigabyte boards came very close to satisfying our
>   needs but fell short in the following ways:
>   1) The Tyan board (model S2466) will not do WOL, and does not
>      properly ignore keyboard absence.

Those are both likely fixed with BIOS updates.

>  It does, however, boot reliably
> via PXE boot and will search repeatedly (even forever) for a boot
> server until one is found

That is very useful. It's much better than what other, earlier PXE
implementations do: terminate and leave the machine in a useless state.

[[ The PXE spec forces all of the server parts to be modified.  And to
correctly implement the spec, the PXE server parts really have to built
together as one program to communication with each other.  But the stuff
the PXE authors controlled, the BIOS, isn't changed when they add PXE on
top. ]]

> (useful for times when the boot server is slow to respond to the boot
> request).

Another reason that we had to write our own PXE server...

>   2) The Gigabyte board (model 7DPXDW-P) does do WOL and PXE boot and does
>      properly ignore an absent keyboard.  However WOL works only in
>      soft-poweroff mode

Do you mean that the OS has to initialize the NIC first?
What NIC does it use?

>      of power-supply from line voltage via a power strip).  Also the PXE
>      boot sequence gives up after 5 tries and requires hitting the reset
>      switch to initiate another boot attempt (not useful for when the boot
>      server is too slow to respond during the 5 tries).

More precisely, 4 timeout-retransmits, before that single-threaded,
single-interface PXE client exits and different single-threaded PXE
tries the next interface.  After trying the interfaces, one-by-one, it
the BIOS tries the next boot media.  If there isn't one, the BIOS just
goes into a busy-loop.

A proper implementation would send the PXE requests on all interfaces at
once, and then select from among the replies.  But the standard doesn't
say that explicitly, so...

Donald Becker				becker at
Scyld Computing Corporation
410 Severn Ave. Suite 210		Scyld Beowulf cluster system
Annapolis MD 21403			410-990-9993

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