14 Jul
2004
14 Jul
'04
11:28 a.m.
On Wed, Jul 14, 2004 at 09:38:54AM +0200, Ed wrote:
I have some conflicting info here. On one hand the
literature says that
DEC rebadged the CDC9762 as RM02 and RM03s...
OTOH, the CDC has a SMD interface yet the RM02/03 has a MASSBUS interface.
Furthermore, the CDC is listed to be at 80MB, yet the RM02/03 apparently
has 67MB only.
So, which is true? I'm confused.
Both... as shipped, the CDC 9762 is 80MB formatted; as shipped, the
DEC RM02/RM03 is 67MB from the same mechanism. The bottom of the
DEC RM02/RM03 is filled with DEC electronics that had a MASSBUS
interface on one end, and a 62-pin/26-pin interface that is *almost*
SMD. In reality, DEC made a couple of changes to the CDC cards in the
card cage in the back of the drive, so it's not trivial to take an RM02
and make it back into a 9762 unless you happen to have a set of original
CDC cards.
There's something about the logical layout of the RM02/RM03 that either
ignores some part of the drive capacity, or else it's using 13MB as
spare tracks. And it's not just on a real RM02/RM03; at SRC, we had
a 160MB Fuji SMD drive on our SI9900 controller as a system drive for
our VAX-11/750. It appeared to the VAX as a pair of RM03s, down to the
67MB available capacity (i.e., the driver wasn't patched to try to make
the 160MB drive _look_ like a single 160MB drive, unlike our Fuji Eagle,
that _was_ a patched RM05 to the system).
--
Ethan Dicks, A-130-S Current South Pole Weather at 14-Jul-2004 13:40 Z
South Pole Station
PSC 468 Box 400 Temp -75 F (-59.5 C) Windchill -113.8 F (-81 C)
APO AP 96598 Wind 11.7 kts Grid 034 Barometer 667.9 mb (11086. ft)
Ethan.Dicks(a)amanda.spole.gov http://penguincentral.com/penguincentral.html