From rfournier@pacbell.net Mon Dec 23 05:45:31 1996
Path: ashpoly!cascade!transat!eunet-fr!teletel!pacbell!rfournier
From: rfournier@pacbell.net (Rodrigo Fournier)
Newsgroups: comp.sys.m68k
Subject: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Dec23.054531.4625@pacbell.net>
Date: Mon, 23 Dec 1996 05:45:31 GMT
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Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.

Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.
The board features two 68000 CPUs clocked at 12 MHz sharing a dual-ported 128KB static RAM bank.

One 28-pin EPROM socket (labeled U14) is completely empty. What firmware was supposed to be in that socket?

-- 
Rodrigo Fournier | rfournier@pacbell.net
PGP Key fingerprint: 10A3 6FC0 6217 D123
"Keep the channels open."

From tpopov@cam.ac.uk Wed Dec 25 00:52:31 1996
Path: ashpoly!cascade!mxgate!coyoacan!cam!tpopov
From: tpopov@cam.ac.uk (Takeshi Popov)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Dec25.005231.3356@cam.ac.uk>
Date: Wed, 25 Dec 1996 00:52:31 GMT
References: <1996Dec23.054531.4625@pacbell.net>
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In article <1996Dec23.054531.4625@pacbell.net>, rfournier@pacbell.net (Rodrigo Fournier) writes:
> Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.
> Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.

Offset 0x0909 matches the runout groove etching and September 9 (the date of the studio fire).

Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin!

-- 
Takeshi Popov -- University of Cambridge Computer Laboratory
"When every node is whole, the channel opens."

From fvasiliev@utexas.edu Wed Dec 25 15:14:31 1996
Path: ashpoly!cascade!transat!ukc!fennimore!utexas!fvasiliev
From: fvasiliev@utexas.edu (Freya Vasiliev)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Dec25.151431.7534@utexas.edu>
Date: Wed, 25 Dec 1996 15:14:31 GMT
References: <1996Dec23.054531.4625@pacbell.net>
Organization: University of Texas at Austin
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In article <1996Dec23.054531.4625@pacbell.net>, rfournier@pacbell.net (Rodrigo Fournier) writes:
> Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.
> Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.

Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop.

-- 
Freya Vasiliev -- University of Texas at Austin
"A soul is not exclusive to biology."