Simulated disk drive for RT-11?

[Ethan Dicks]

On 6/7/05, Pete Turnbull <pete at dunnington.u-net.com> wrote:
> On Jun 6 2005, 22:46, Allison wrote:
> 
> > Note there were differenet backplanes used in the BA23 those
> > that were compatable with uVAX-1, those that were uVAX-II
> > and the microPDP-11. Use the wrong one with the desired CPU
> > and bad results happen.
> 
> I've never seen more than one type of backplane in a BA23, and only one
> is listed in my manuals: H9278-A.  It's compatible with all of
> microPDP-11, uVAX-I and uVAX-II without so much as a jumper change.
>  Are you thinking of something else?

Agreed... One of the MicroVAX-IIs I own was originally shipped from
DEC in 1984 as a uVAX-I, then upgraded (for $17,000!) and I don't
remember a backplane swap being part of the deal.

Every BA-23 I have seen is Q22-CD for 3 slots, then Q22-serpentine for
the remaining slots.

Is there another kind?

-ethan