Subject: Re: VAXstation 3100 fun.
To: Bertram Barth <bertram@ifib.uni-karlsruhe.de>
From: Matthew N. Dodd <winter@jurai.net>
List: port-vax
Date: 09/29/1997 14:39:34
Ah this fits...  Time to get the source now...

On Mon, 29 Sep 1997, Bertram Barth wrote:
> I'm not absolutely sure, but this behaviour might be due to the way
> LANCE is adressing its memory and interacting with the ROM routines.
> 
> LANCE adresses within an 16MB area, either lower 16MB or upper 16MB,
> switchable by one bit in some register. AFAIK the ROM routines initialize
> the LANCE in a way that it's reading and wirting into an area located
> at the highest available memory. The NetBSD/vax boot-routines use an
> fixed area in the lower 16MB of memory. Without re-initializing the
> LANCE in case of > 16MB, thus both sides are using the same offset into
> different areas of memory, this is the reason why netbooting doesn't
> work.
> 
> For 3100/76 LANCE is re-initialized and should work with any size of
> memory (un-tested), AFAIK for other 3100's the reinitialization is
> not implemented.
> 
> Ciao,
> 	bertram
> 
> PS: The above mentioned register is not an register of the LANCE chip,
>     but some internal register. Anyway, correct initialization of LANCE
>     wrt. to this register should solve the netboot problems...

/* 
   Matthew N. Dodd		| A memory retaining a love you had for life	
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