From fsuzuki@clari.net Fri Apr 26 12:30:21 1996
Path: ashpoly!bigsur!pacrim!krgate!eunha!clari!fsuzuki
From: fsuzuki@clari.net (Fiona Suzuki)
Newsgroups: comp.sys.m68k
Subject: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Apr26.123021.2567@clari.net>
Date: Fri, 26 Apr 1996 12:30:21 GMT
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Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.

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?

-- 
Fiona Suzuki
Tape trading list upon request. SASE required for international mail.

From dduarte@uu.net Sun Apr 28 11:46:21 1996
Path: ashpoly!cascade!mxgate!coyoacan!uu!dduarte
From: dduarte@uu.net (Diego Duarte)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Apr28.114621.5200@uu.net>
Date: Sun, 28 Apr 1996 11:46:21 GMT
References: <1996Apr26.123021.2567@clari.net>
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In article <1996Apr26.123021.2567@clari.net>, fsuzuki@clari.net (Fiona Suzuki) writes:
> Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.
> Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.

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

-- 
Diego Duarte | dduarte@uu.net
PGP Key fingerprint: 1EA9 C98D AB24 7922
"Keep the channels open."

From lpark@inria.fr Tue Apr 30 03:51:21 1996
Path: ashpoly!bigsur!pacrim!krgate!eunha!inria!lpark
From: lpark@inria.fr (Lucia Park)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Apr30.035121.6718@inria.fr>
Date: Tue, 30 Apr 1996 03:51:21 GMT
References: <1996Apr26.123021.2567@clari.net>
Organization: INRIA Rocquencourt
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In article <1996Apr26.123021.2567@clari.net>, fsuzuki@clari.net (Fiona Suzuki) writes:
> Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.

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.

-- 
Lucia Park
Tape trading list upon request. SASE required for international mail.

From mstewart@illinois.edu Wed May 01 06:53:21 1996
Path: ashpoly!cascade!bigsur!illinois!mstewart
From: mstewart@illinois.edu (Mikhail Stewart)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996May01.065321.6817@illinois.edu>
Date: Wed, 01 May 1996 06:53:21 GMT
References: <1996Apr26.123021.2567@clari.net>
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In article <1996Apr26.123021.2567@clari.net>, fsuzuki@clari.net (Fiona Suzuki) writes:
> Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.

The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon.

-- 
=== Mikhail Stewart ===
Dept of Electrical Engineering, University of Illinois Urbana-Champaign
"Tape doesn't lie at 02:14. Ears do."

From teriksson@berkeley.edu Thu May 02 11:12:21 1996
Path: ashpoly!cascade!transat!sunet!nordrelay!berkeley!teriksson
From: teriksson@berkeley.edu (Tyler Eriksson)
Newsgroups: comp.sys.m68k
Subject: Re: [SPECULATION] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996May02.111221.1454@berkeley.edu>
Date: Thu, 02 May 1996 11:12:21 GMT
References: <1996Apr26.123021.2567@clari.net>
Organization: UC Berkeley Department of EECS
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In article <1996Apr26.123021.2567@clari.net>, fsuzuki@clari.net (Fiona Suzuki) writes:
> Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.

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

-- 
Tyler Eriksson
Opinions expressed are solely my own and not those of UC Berkeley Department of EECS.
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