From aokonkwo@purdue.edu Sun Jul 16 15:28:54 1995
Path: ashpoly!cascade!transat!sunet!nordrelay!purdue!aokonkwo
From: aokonkwo@purdue.edu (Aiko Okonkwo)
Newsgroups: comp.sys.m68k
Subject: WTB/WTT: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jul16.152854.5095@purdue.edu>
Date: Sun, 16 Jul 1995 15:28:54 GMT
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Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.

The board features two 68000 CPUs clocked at 12 MHz sharing a dual-ported 128KB static RAM bank.
At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII.

Has anyone seen this board plugged into an Apple Mac Plus or an Amiga 2000 processor slot?

-- 
Aiko Okonkwo | aokonkwo@purdue.edu
PGP Key fingerprint: C75D E700 4EE0 73BA
"Keep the channels open."

From tjohansson@rwth-aachen.de Mon Jul 17 12:35:54 1995
Path: ashpoly!cascade!brgate!saturno!rwth-aachen!tjohansson
From: tjohansson@rwth-aachen.de (Thiago Johansson)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jul17.123554.8541@rwth-aachen.de>
Date: Mon, 17 Jul 1995 12:35:54 GMT
References: <1995Jul16.152854.5095@purdue.edu>
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In article <1995Jul16.152854.5095@purdue.edu>, aokonkwo@purdue.edu (Aiko Okonkwo) writes:
> Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.

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

-- 
Thiago Johansson | tjohansson@rwth-aachen.de
PGP Key fingerprint: F7D2 53B5 E243 84BC
"Keep the channels open."

From epopov@clari.net Wed Jul 19 15:10:54 1995
Path: ashpoly!cascade!transat!sunet!nordrelay!clari!epopov
From: epopov@clari.net (Élodie Popov)
Newsgroups: comp.sys.m68k
Subject: Re: WTB/WTT: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jul19.151054.9473@clari.net>
Date: Wed, 19 Jul 1995 15:10:54 GMT
References: <1995Jul16.152854.5095@purdue.edu> <1995Jul17.123554.8541@rwth-aachen.de>
Organization: ClariNet Communications Corp
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In article <1995Jul17.123554.8541@rwth-aachen.de>, tjohansson@rwth-aachen.de (Thiago Johansson) writes:
> Offset 0x0909 matches the runout groove etching and September 9 (the date of the studio fire).

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

-- 
Élodie Popov
Opinions expressed are solely my own and not those of ClariNet Communications Corp.
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