Subject: Re: New virtual bus.
To: Anders Magnusson <>
From: Brian D Chase <>
List: port-vax
Date: 07/13/1999 14:16:21
On Tue, 13 Jul 1999, Anders Magnusson wrote:

> Because mainbus should only be used as a "top-level bus holder" for
> the different machine types. Therefore it is already splitted like:
> sbi*	at mainbus0	# 780, 8600
> cmi*	at mainbus0	# 750
> bi*	at mainbus0	# 8200
> vsbus0	at mainbus0	# 2000, 3100, 4000/x0
> mvbus0	at mainbus0	# MV2, MV3, 3[3-9]00, 4000/x00
> The here given bus is actually the main bus in the specific architecture.
> "Nexus" in the old config system were used as the "master bus" but the
> same for all architectures, which made the structure a little bit 
> chaotic in the code.

I think maybe the vsbus / mvbus are less than ideal names for the busses.

For example, will the MicroVAX 3100/{10,20,10e,20e} or the later model 
MicroVAX 3100/{40,80,90} models fall under the vsbus structure or the
mvbus structure?

I think we've determined that systems like the MicroVAX 3100/10 more
closely conform to the layout of the vsbus, but the MicroVAX 3100/10 isn't
a VAXstation.  I've no idea what you'd name the bus for such systems.  I
suppose we could say that the "vs" in vsbus stands for "VAX-small".

(You did ask for feedback :-)

Brian "JARAI" Chase | | VAXZilla LIVES!!!