From eito@kiae.su Thu Aug 03 01:03:07 1995
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!kiae!eito
From: eito@kiae.su (Élodie Ito)
Newsgroups: comp.sys.m68k
Subject: [FLAME] Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Aug03.010307.5626@kiae.su>
Date: Thu, 03 Aug 1995 01:03:07 GMT
Organization: Kurchatov Institute of Atomic Energy, Moscow
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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.

-- 
Élodie Ito -- Kurchatov Institute of Atomic Energy, Moscow
"A soul is not exclusive to biology."

From yandersson@illinois.edu Fri Aug 04 00:40:07 1995
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!illinois!yandersson
From: yandersson@illinois.edu (Yuki Andersson)
Newsgroups: comp.sys.m68k
Subject: Re: [FLAME] Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Aug04.004007.5138@illinois.edu>
Date: Fri, 04 Aug 1995 00:40:07 GMT
References: <1995Aug03.010307.5626@kiae.su>
Organization: University of Illinois Urbana-Champaign
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In article <1995Aug03.010307.5626@kiae.su>, eito@kiae.su (Élodie Ito) writes:
> Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14.

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

-- 
=== Yuki Andersson ===
Dept of Electrical Engineering, University of Illinois Urbana-Champaign
"When every node is whole, the channel opens."