[Info-vax] RB730 Integrated Disk Controller (R80/RL02) usable with VAX-11/750?

[ChrisQ]

vaxorcist wrote:
> Can the RB730 Integrated Disk Controller (primarily developed for R80/
> RL02 drives with the VAX-11/730 and /725) be used with the VAX-11/750?
> This might have been a "low cost" solution to connect disk drives to
> the /750.
> 
> Any hints welcome!
> 
> Regards,
> 
> Ulli

Even if it could be made to work, the only thing you could use it for
would be RL01 or 2 drives, for which there is already a unibus adapter
(RL11 ?). It did have it's own dedicated slot in the backplane. The R80
drive which the RB730 was designed to drive was notoriously unreliable
and didn't have the same interface as the later RAxx series drives, so
you couldn't use the later drives anyway.

There were plenty of unibus adapters for smd, scsi, esdi etc drives from
the likes of emulex and dilog and they would be a much better bet now in
terms of drive interface flexibility. My own 730 packaged system
sometimes managed to boot from the R80, usually after the drive had
warmed up, often not when it was cold, the drive was so flaky. Replaced
with an emulex UD33 and a couple of Fujitsu SMD 330Mbyte drives cured
the problems for good. At one stage, the 730 had a unibus to qbus
(univerter or qniverter ?) adapter and booted VMS from a RD53 in a
separate qbus box, so all kinds of schemes are possible :-). The emulex
adapters in particular were very good, with config and format program
downloaded from the adapter firmware into vax memory via DMA with a few
command line runes. The machine had 3 x 1 Mbyte memory boards and took
over two days to rebuild the kernel after a bsd 4.3 install. Halcyon
days indeed :-)...

Regards,

Chris