From deriksson@uu.net Wed Nov 15 15:54:04 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!uu!deriksson
From: deriksson@uu.net (Dmitri Eriksson)
Newsgroups: comp.sys.m68k
Subject: [FLAME] Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Nov15.155404.4398@uu.net>
Date: Wed, 15 Nov 1995 15:54:04 GMT
Organization: UUNET Technologies, Falls Church VA
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Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14.

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.

-- 
Dmitri Eriksson -- UUNET Technologies, Falls Church VA
"The hatch is open. Is anyone listening?"

From mfischer@titech.ac.jp Fri Nov 17 10:52:04 1995
Path: ashpoly!cascade!transat!sunet!nordrelay!titech!mfischer
From: mfischer@titech.ac.jp (Min-jun Fischer)
Newsgroups: comp.sys.m68k
Subject: Re: [FLAME] Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Nov17.105204.1820@titech.ac.jp>
Date: Fri, 17 Nov 1995 10:52:04 GMT
References: <1995Nov15.155404.4398@uu.net>
Organization: Tokyo Institute of Technology Computer Centre
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In article <1995Nov15.155404.4398@uu.net>, deriksson@uu.net (Dmitri Eriksson) writes:
> Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14.
> Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14.

Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984.

-- 
Min-jun Fischer -- Tokyo Institute of Technology Computer Centre
"When every node is whole, the channel opens."