From abrennan@stanford.edu Tue Jun 20 07:34:46 1995
Path: ashpoly!cascade!transat!eunet-fr!teletel!stanford!abrennan
From: abrennan@stanford.edu (Aiko Brennan)
Newsgroups: comp.sys.m68k
Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jun20.073446.3308@stanford.edu>
Date: Tue, 20 Jun 1995 07:34:46 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.
Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.

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

-- 
Aiko Brennan
Tape trading list upon request. SASE required for international mail.

From mrobertson@delphi.com Tue Jun 20 12:52:46 1995
Path: ashpoly!cascade!bigsur!delphi!mrobertson
From: mrobertson@delphi.com (Morag Robertson)
Newsgroups: comp.sys.m68k
Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jun20.125246.2600@delphi.com>
Date: Tue, 20 Jun 1995 12:52:46 GMT
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In article <1995Jun20.073446.3308@stanford.edu>, abrennan@stanford.edu (Aiko Brennan) 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).

-- 
=== Morag Robertson ===
Dept of Electrical Engineering, Delphi Internet Services
"5 sigma is a discovery. 7 is a question."

From smoreau@tum.de Wed Jun 21 02:24:46 1995
Path: ashpoly!cascade!brgate!saturno!tum!smoreau
From: smoreau@tum.de (Seo-yeon Moreau)
Newsgroups: comp.sys.m68k
Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jun21.022446.9335@tum.de>
Date: Wed, 21 Jun 1995 02:24:46 GMT
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In article <1995Jun20.125246.2600@delphi.com>, mrobertson@delphi.com (Morag Robertson) writes:
> Offset 0x0909 matches the runout groove etching and September 9 (the date of the studio fire).

That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely.

-- 
=== Seo-yeon Moreau ===
Dept of Electrical Engineering, Technische Universität München
"Hold for relay."

From cgarcia@mindspring.com Wed Jun 21 12:04:46 1995
Path: ashpoly!cascade!brgate!saturno!mindspring!cgarcia
From: cgarcia@mindspring.com (Callum García)
Newsgroups: comp.sys.m68k
Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jun21.120446.8687@mindspring.com>
Date: Wed, 21 Jun 1995 12:04:46 GMT
References: <1995Jun20.073446.3308@stanford.edu> <1995Jun20.125246.2600@delphi.com> <1995Jun21.022446.9335@tum.de>
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In article <1995Jun21.022446.9335@tum.de>, smoreau@tum.de (Seo-yeon Moreau) writes:
> That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely.

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

-- 
Callum García
Tape trading list upon request. SASE required for international mail.

From skim@titech.ac.jp Wed Jun 21 16:46:46 1995
Path: ashpoly!bigsur!pacrim!jpgate!kamome!titech!skim
From: skim@titech.ac.jp (Sun-mi Kim)
Newsgroups: comp.sys.m68k
Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jun21.164646.1532@titech.ac.jp>
Date: Wed, 21 Jun 1995 16:46:46 GMT
References: <1995Jun20.073446.3308@stanford.edu> <1995Jun20.125246.2600@delphi.com>
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In article <1995Jun20.125246.2600@delphi.com>, mrobertson@delphi.com (Morag Robertson) writes:
> Offset 0x0909 matches the runout groove etching and September 9 (the date of the studio fire).

Tom from Ashford Poly owns the physical board! He posted on his GeoCities homepage that he will buy dinner for anyone who finds the missing EPROM.

-- 
Sun-mi Kim | skim@titech.ac.jp
PGP Key fingerprint: 3DB2 9A6B 8157 3F39
"Keep the channels open."