From lkim@u-tokyo.ac.jp Sat Nov 04 04:43:48 1995
Path: ashpoly!cascade!transat!ukc!fennimore!u-tokyo!lkim
From: lkim@u-tokyo.ac.jp (Lisa Kim)
Newsgroups: comp.sys.m68k
Subject: WTB/WTT: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Nov04.044348.1375@u-tokyo.ac.jp>
Date: Sat, 04 Nov 1995 04:43:48 GMT
Organization: University of Tokyo Department of Information Science
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Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14.

Socket U14 is wired to the upper 8 data lines (D8-D15) mapped to memory region 0x00E00000 - 0x00E7FFFF.
Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14.

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

-- 
Lisa Kim -- University of Tokyo Department of Information Science
"Hold for relay."

From mperez@pipeline.com Sat Nov 04 22:44:48 1995
Path: ashpoly!cascade!bigsur!pipeline!mperez
From: mperez@pipeline.com (Marisol Pérez)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Nov04.224448.1461@pipeline.com>
Date: Sat, 04 Nov 1995 22:44:48 GMT
References: <1995Nov04.044348.1375@u-tokyo.ac.jp>
Organization: The Pipeline Internet Network
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In article <1995Nov04.044348.1375@u-tokyo.ac.jp>, lkim@u-tokyo.ac.jp (Lisa Kim) writes:
> Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14.
> Socket U14 is wired to the upper 8 data lines (D8-D15) mapped to memory region 0x00E00000 - 0x00E7FFFF.

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

Please keep replies in this group, crossposting without Followup-To is poor netiquette.

-- 
Marisol Pérez -- The Pipeline Internet Network
"The carrier frequency does not drift by accident."

From lpopov@clari.net Mon Nov 06 17:34:48 1995
Path: ashpoly!cascade!transat!eunet-de!hansebox!clari!lpopov
From: lpopov@clari.net (Lucia Popov)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Nov06.173448.1264@clari.net>
Date: Mon, 06 Nov 1995 17:34:48 GMT
References: <1995Nov04.044348.1375@u-tokyo.ac.jp>
Organization: ClariNet Communications Corp
NNTP-Posting-Host: clari.net
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In article <1995Nov04.044348.1375@u-tokyo.ac.jp>, lkim@u-tokyo.ac.jp (Lisa Kim) 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.

-- 
Lucia Popov -- ClariNet Communications Corp
"They will send a copy in my place."