New to VAX (4000/200)

[Jochen Kunz]

On Thu, 01 May 2008 09:21:50 -0400
Sridhar Ayengar <ploopster at gmail.com> wrote:

> I thought the 4000-200 was designed to work in the BA123 or something 
> similar. 
The 4k2 CPU doesn't fit into a BA123 or BA23 because a connector on the
front of the CPU card is too high and the slots in the BA123 / BA23 are
to narrow. (Well, maybe it will fit if you mount it into the second
slot. But this leaves only one Q/CD slot for memory in case of the
BA23.) Usual for the 4k2 are the BA213 or BA215 "S-Box" style
enclosures. (BA215 is about half a BA213.) The slot with is larger in
the S-Boxes and there are special QBus cards with "S-Box handles".
But there are a few 4k2 in BA440 boxes. I suppose DEC switched from
BA213 to BA440 style boxes at the end of the 4k2 live time. 

> The BA440 has those processor-memory interconnect slots to
> the right of the Qbus, right?
Yes. IIRC this special CPU slot also brings one of the two DSSI buses
to the backplane.
-- 


tsch__,
       Jochen

Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/