From smoreau@delphi.com Wed May 08 22:51:59 1996
Path: ashpoly!cascade!transat!ukc!fennimore!delphi!smoreau
From: smoreau@delphi.com (Steve Moreau)
Newsgroups: comp.sys.m68k
Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996May08.225159.2820@delphi.com>
Date: Wed, 08 May 1996 22:51:59 GMT
Organization: Delphi Internet Services
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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'.
CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit.

Schematic diagram in ASCII uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/twin68_array.asc.

-- 
=== Steve Moreau ===
Dept of Electrical Engineering, Delphi Internet Services
"Do not worship the copy."

From inakamura@demon.co.uk Fri May 10 14:33:59 1996
Path: ashpoly!bigsur!pacrim!jpgate!kamome!demon!inakamura
From: inakamura@demon.co.uk (Ines Nakamura)
Newsgroups: comp.sys.m68k
Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996May10.143359.9152@demon.co.uk>
Date: Fri, 10 May 1996 14:33:59 GMT
References: <1996May08.225159.2820@delphi.com>
Organization: Demon Internet Services UK
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In article <1996May08.225159.2820@delphi.com>, smoreau@delphi.com (Steve Moreau) writes:
> Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.

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

-- 
=== Ines Nakamura ===
Dept of Electrical Engineering, Demon Internet Services UK
"Hold for relay."