SMD disk specifications

Mattis Lind mattislind at
Mon Dec 16 00:22:08 CST 2019

måndag 16 december 2019 skrev Eric Smith via cctalk <cctalk at>:

> On Sun, Dec 15, 2019 at 3:05 AM jim stephens via cctalk <
> cctalk at> wrote:
> > I don't know that I recall SMD being a product as much as a reference to
> > the interface they had though.
> >
> "SMD" was in fact a product name. The CDC976x, BK4XX, BK5XX, BK6XX, and
> BK7XX series drives had the official name "CDC(R) Storage Module Drive",
> from whence came the "SMD" name for the interface, starting with the 9760
> in 1973.  MMD and CMD drives came along a few years later. AFAIK the MMD
> drives weren't too popular in the early years, but gained traction in the
> 1980s. CMD drives, on the other hand, were an instant hit, starting with
> the 9427 "Hawk" drive in 1977.

The Hawk was quite different from the Phoenix. Actually it was not a
Cartridge Module Drive, rather it was called Cartridge  Disk Drive. While
the CMD and SMD drives could be used on the same host interface the Hawk
could not since the interface was different from the SMD interface.

More information about the cctech mailing list