From lmuller@cmu.edu Mon Nov 28 11:08:35 1994
Path: ashpoly!cascade!mxgate!coyoacan!cmu!lmuller
From: lmuller@cmu.edu (Lisa Müller)
Newsgroups: comp.sys.m68k
Subject: [SPECULATION] Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1994Nov28.110835.3967@cmu.edu>
Date: Mon, 28 Nov 1994 11:08:35 GMT
Organization: Carnegie Mellon University School of CS
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Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board.

Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14.
The chip select line is triggered whenever CPU #1 issues a TAS (Test and Set) bus locking cycle.

Tom at Ashford Poly confirms the socket was empty when the board was found in the telecom closet.

-- 
Lisa Müller
Opinions expressed are solely my own and not those of Carnegie Mellon University School of CS.
------------------------------------------------------------

From klindqvist@illinois.edu Mon Nov 28 13:44:35 1994
Path: ashpoly!cascade!transat!ukc!fennimore!illinois!klindqvist
From: klindqvist@illinois.edu (Kenji Lindqvist)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1994Nov28.134435.2196@illinois.edu>
Date: Mon, 28 Nov 1994 13:44:35 GMT
References: <1994Nov28.110835.3967@cmu.edu>
Organization: University of Illinois Urbana-Champaign
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In article <1994Nov28.110835.3967@cmu.edu>, lmuller@cmu.edu (Lisa Müller) writes:
> Further progress on reverse-engineering the empty socket U14 on the TWIN-68 Rev C coprocessor board.
> Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14.

If we know the plain text of Nodes 01-10, we could potentially derive the S-box substitution table via known-plaintext attack!

My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise!

-- 
Kenji Lindqvist | klindqvist@illinois.edu
PGP Key fingerprint: 3DFE 520E 3F84 7448
"Keep the channels open."