From rpark@mit.edu Wed Jan 03 10:27:35 1996
Path: ashpoly!cascade!transat!sunet!nordrelay!mit!rpark
From: rpark@mit.edu (Raj Park)
Newsgroups: comp.sys.m68k
Subject: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Jan03.102735.8762@mit.edu>
Date: Wed, 03 Jan 1996 10:27:35 GMT
Organization: Massachusetts Institute of Technology
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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.
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?

-- 
Raj Park | rpark@mit.edu
PGP Key fingerprint: B56B 9CD0 3513 405A
"Keep the channels open."

From bjohansson@uni-hamburg.de Wed Jan 03 22:05:35 1996
Path: ashpoly!cascade!transat!eunet-de!hansebox!uni-hamburg!bjohansson
From: bjohansson@uni-hamburg.de (Bill Johansson)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Jan03.220535.7465@uni-hamburg.de>
Date: Wed, 03 Jan 1996 22:05:35 GMT
References: <1996Jan03.102735.8762@mit.edu>
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In article <1996Jan03.102735.8762@mit.edu>, rpark@mit.edu (Raj Park) 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.

-- 
Bill Johansson | bjohansson@uni-hamburg.de
PGP Key fingerprint: F38A 96E5 D7E9 90EF
"Keep the channels open."