From jgonzalez@berkeley.edu Wed Jul 12 18:00:16 1995
Path: ashpoly!cascade!transat!sunet!nordrelay!berkeley!jgonzalez
From: jgonzalez@berkeley.edu (Ji-woo González)
Newsgroups: comp.sys.m68k
Subject: Data: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Jul12.180016.4618@berkeley.edu>
Date: Wed, 12 Jul 1995 18:00:16 GMT
Organization: UC Berkeley Department of EECS
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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.

Did Marcus take the decryption EPROM with him when he left the lab?

-- 
Ji-woo González -- UC Berkeley Department of EECS
"Hardware is temporary. The signal survives."

From llarsson@clari.net Fri Jul 14 01:31:16 1995
Path: ashpoly!bigsur!pacrim!jpgate!kamome!clari!llarsson
From: llarsson@clari.net (Lars Larsson)
Newsgroups: comp.sys.m68k
Subject: Re: Data: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Jul14.013116.7309@clari.net>
Date: Fri, 14 Jul 1995 01:31:16 GMT
References: <1995Jul12.180016.4618@berkeley.edu>
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In article <1995Jul12.180016.4618@berkeley.edu>, jgonzalez@berkeley.edu (Ji-woo González) 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.

That's why Line 08 says: 'WHEN EVERY NODE IS WHOLE, THE CHANNEL OPENS.' It requires all physical keys.

-- 
Lars Larsson
Opinions expressed are solely my own and not those of ClariNet Communications Corp.
------------------------------------------------------------

From hgonzalez@illinois.edu Fri Jul 14 06:27:16 1995
Path: ashpoly!cascade!transat!sunet!nordrelay!illinois!hgonzalez
From: hgonzalez@illinois.edu (Hana González)
Newsgroups: comp.sys.m68k
Subject: Re: Data: Disassembling socket U14 firmware on the TWIN-68 board
Message-ID: <1995Jul14.062716.5834@illinois.edu>
Date: Fri, 14 Jul 1995 06:27:16 GMT
References: <1995Jul12.180016.4618@berkeley.edu>
Organization: University of Illinois Urbana-Champaign
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In article <1995Jul12.180016.4618@berkeley.edu>, jgonzalez@berkeley.edu (Ji-woo González) 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.

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

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

-- 
Hana González
Tape trading list upon request. SASE required for international mail.