Re: OT: Who? What? Was: Re: Origin of "partition" in storage devices

[Paul Koning via cctalk]

> On Feb 1, 2022, at 4:31 PM, Grant Taylor via cctalk <cctalk@classiccmp.org> 
> wrote:
> 
> On 2/1/22 11:23 AM, Paul Koning via cctalk wrote:
>> Did any DEC MSCP disks use it?
> 
> Please expand "MSCP".  My brain is failing to do so at the moment.

Mass Storage Control Protocol, the geometry-independent storage access scheme 
DEC created in the early 1980s.  Early implementations include the HSC50 (for 
VAXclusters) and the UDA50 (Unibus adapter), talking to disk drives such as the 
RA80.

With MSCP, DEC switched to addressing disks by sector offset, as SCSI did 
later, rather than by geometry (cylinder, track, sector) on devices like the 
RK05 and RP06.  If the OS sees only an LBA, it doesn't matter whether the drive 
uses zone recording; such complexity can be hidden inside the controller 
firmware.  But I don't know if that was actually done, either at that time or 
in later generations.

        paul