From tmuller@illinois.edu Fri Jan 13 02:47:19 1995
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From: tmuller@illinois.edu (Tomas Müller)
Newsgroups: comp.sys.m68k
Subject: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan13.024719.4452@illinois.edu>
Date: Fri, 13 Jan 1995 02:47:19 GMT
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Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project.

The board features two 68000 CPUs clocked at 12 MHz sharing a dual-ported 128KB static RAM bank.
CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit.

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

-- 
Tomas Müller -- University of Illinois Urbana-Champaign
"Hold for relay."

From kgarcia@purdue.edu Fri Jan 13 10:07:19 1995
Path: ashpoly!cascade!brgate!saturno!purdue!kgarcia
From: kgarcia@purdue.edu (Katrin García)
Newsgroups: comp.sys.m68k
Subject: Re: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan13.100719.6306@purdue.edu>
Date: Fri, 13 Jan 1995 10:07:19 GMT
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In article <1995Jan13.024719.4452@illinois.edu>, tmuller@illinois.edu (Tomas Müller) writes:
> Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project.

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.

-- 
Katrin García
Opinions expressed are solely my own and not those of Purdue University Engineering Computer Network.
------------------------------------------------------------

From rrodriguez@ox.ac.uk Fri Jan 13 10:56:19 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!ox!rrodriguez
From: rrodriguez@ox.ac.uk (Raj Rodríguez)
Newsgroups: comp.sys.m68k
Subject: Re: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan13.105619.3668@ox.ac.uk>
Date: Fri, 13 Jan 1995 10:56:19 GMT
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In article <1995Jan13.024719.4452@illinois.edu>, tmuller@illinois.edu (Tomas Müller) writes:
> Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project.

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

-- 
=== Raj Rodríguez ===
Dept of Electrical Engineering, Oxford University Computing Laboratory
"We don't sign stars. We build them."

From bhughes@utexas.edu Fri Jan 13 20:01:19 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!utexas!bhughes
From: bhughes@utexas.edu (Brian Hughes)
Newsgroups: comp.sys.m68k
Subject: Re: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan13.200119.3707@utexas.edu>
Date: Fri, 13 Jan 1995 20:01:19 GMT
References: <1995Jan13.024719.4452@illinois.edu> <1995Jan13.105619.3668@ox.ac.uk>
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In article <1995Jan13.105619.3668@ox.ac.uk>, rrodriguez@ox.ac.uk (Raj Rodríguez) writes:
> Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop.

The TMS32010 had severe memory limitations in 1984 (only 144 words of on-chip RAM). Dual 68000s gave them full 16MB address space.

-- 
Brian Hughes | bhughes@utexas.edu
PGP Key fingerprint: 176B 6601 F14C DA03
"Keep the channels open."

From arobertson@kth.se Fri Jan 13 23:54:19 1995
Path: ashpoly!cascade!bigsur!kth!arobertson
From: arobertson@kth.se (Amy Robertson)
Newsgroups: comp.sys.m68k
Subject: Re: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Jan13.235419.3190@kth.se>
Date: Fri, 13 Jan 1995 23:54:19 GMT
References: <1995Jan13.024719.4452@illinois.edu> <1995Jan13.100719.6306@purdue.edu>
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In article <1995Jan13.100719.6306@purdue.edu>, kgarcia@purdue.edu (Katrin García) writes:
> 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.

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

-- 
Amy Robertson -- Royal Institute of Technology, Stockholm
"In theory there is no difference between theory and practice."