Rugged Nova/1601

Christian Kennedy chris at
Sun Nov 11 23:00:11 CST 2018

On 11/6/18 1:22 AM, erik--- via cctech wrote:

> Yes, lot of metal inside those Rolms. Although all Aluminium, they 
> are veeery heavy and I always wondered how many of them also have
> been used in airborne applications, where weight is an issue ;-)

One of the more interesting problems we faced at ROLM MSC (as opposed to
the telecom side) was the fact that all hardware was designed to be
tri-service.  Salt spray and fungal resistance required that the cases
be sealed with thermal frames to conduct heat to external heat
exchangers, but that created interesting issues when sticking the box on
an aircraft (but was a lifesaver with disk drives, as otherwise flying
heads had a tendency to crash with altitude).  The chassis ended up
being quite heavy due to the hammer and drop tests (as others have
noted, intended to simulate the shock of depth charges), as well as the
shaker table tests (driven by a pair of Really Freaking Big McIntosh
audio amps).

The result of all of this was that the machines tended to be much
heavier and thermally complex than they the might have needed to be for
the Air Force, but the desire for commonality in some weapons systems
(GLCM/SLCM comes to mind) across services made the choice a good one.

As for the 1601 (aka AN/UYK-12(V)), it very much did exist and was
exhibited in 1969 at the Fall Joint Computer Conference, one year after
the Nova took its bow, running the same demo software.  It was deployed
as part of the AN/ALR-46 Radar warning system, which was found on the
B-52, F-4 and F-111

Note that even the 1601 was a ROLM-specific design that implemented the
DG instruction set under license.  ROLM deviated from this somewhat with
the 1602 and 1666, bolting in their own extensions to the ISA.  The
one-half-ATR chassis MSC-14 is actually a punch, where the S/140 prints
and microcode were used more or less verbatim (although some tweaks were
ultimately needed due to timing issues arising from the different card
form factors); the Hawk was very much a ROLM-specific design and caused
us software types some fits, because the the microcode guys frequently
missed the "reserved, must be zero" and "reserved, may be zero" notes in
Wallach's Eagle Architecture doc (at one point they proposed a
loop-in-microcode approach to implementing the purge ATU instruction
because it only showed up twice in the AOS/VS code base, until it was
pointed out that the damn thing was executed on every context switch...)

Christian Kennedy, Ph.D.
chris at	AF6AP | DB00000692 | PG00029419	PGP KeyID 108DAB97
PGP fingerprint: 4E99 10B6 7253 B048 6685 6CBC 55E1 20A3 108D AB97
"Mr. McKittrick, after careful consideration…"

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