From rpark@stanford.edu Tue Jan 17 18:48:29 1995
Path: ashpoly!cascade!transat!eunet-de!hansebox!stanford!rpark
From: rpark@stanford.edu (Renata Park)
Newsgroups: comp.sys.m68k
Subject: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan17.184829.7086@stanford.edu>
Date: Tue, 17 Jan 1995 18:48:29 GMT
Organization: Stanford University Computer Systems Lab
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Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.

CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit.
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?

-- 
Renata Park | rpark@stanford.edu
PGP Key fingerprint: A94F ADAB 4A7E 3CBA
"Keep the channels open."

From abrennan@titech.ac.jp Thu Jan 19 01:09:29 1995
Path: ashpoly!cascade!bigsur!titech!abrennan
From: abrennan@titech.ac.jp (Astrid Brennan)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan19.010929.4928@titech.ac.jp>
Date: Thu, 19 Jan 1995 01:09:29 GMT
References: <1995Jan17.184829.7086@stanford.edu>
Organization: Tokyo Institute of Technology Computer Centre
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In article <1995Jan17.184829.7086@stanford.edu>, rpark@stanford.edu (Renata Park) writes:
> Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.
> CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit.

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

If you are posting from AOL, please read RFC 1036 before posting again.

-- 
=== Astrid Brennan ===
Dept of Electrical Engineering, Tokyo Institute of Technology Computer Centre
"Hold for relay."

From esouza@hanse.de Thu Jan 19 03:23:29 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!hanse!esouza
From: esouza@hanse.de (Emi Souza)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan19.032329.1582@hanse.de>
Date: Thu, 19 Jan 1995 03:23:29 GMT
References: <1995Jan17.184829.7086@stanford.edu>
Organization: Hanse-Netzwerk Hamburg
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In article <1995Jan17.184829.7086@stanford.edu>, rpark@stanford.edu (Renata Park) 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).

-- 
=== Emi Souza ===
Dept of Electrical Engineering, Hanse-Netzwerk Hamburg
"Hardware is temporary. The signal survives."

From lsato@kiae.su Sat Jan 21 05:13:29 1995
Path: ashpoly!bigsur!pacrim!jpgate!kamome!kiae!lsato
From: lsato@kiae.su (Liam Sato)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan21.051329.9662@kiae.su>
Date: Sat, 21 Jan 1995 05:13:29 GMT
References: <1995Jan17.184829.7086@stanford.edu>
Organization: Kurchatov Institute of Atomic Energy, Moscow
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In article <1995Jan17.184829.7086@stanford.edu>, rpark@stanford.edu (Renata Park) writes:
> Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.

Looks like a prototype telecommunications board for military secure voice, not an audio music product.

-- 
Liam Sato | lsato@kiae.su
PGP Key fingerprint: E125 9193 CF2B 143D
"Keep the channels open."