Subject: Re: VAXstation 3100 fun.
To: None <port-vax@NetBSD.ORG>
From: Allison J Parent <allisonp@world.std.com>
List: port-vax
Date: 09/29/1997 13:47:59
<From: der Mouse <mouse@Rodents.Montreal.QC.CA>
<This sounds suspicious. 16M is 22 bits. Aren't Q-bus addresses 22
Qbus is 22 bits address and 4mb! It takes 24bits to address 16mb. Also the
LANCE chips was not used on Q-BUS( is not a componenet of DEQNA or DELQA).
The Lance appeared in the non-bus boxen such as the VS2000, 3100-, and
VAXmate. I believe it's existance is spawned from the PC market and was
DMA limited to the then generous 16mb space of the systems of the time.
It takes a lot of BITS, PINS or muxing to go for larger address spaces.
The idea of more than 16mb in a non mainframe scale system is relatively
recent.
Allison