From keriksson@berkeley.edu Sat Mar 18 07:55:34 1995
Path: ashpoly!cascade!transat!eunet-de!hansebox!berkeley!keriksson
From: keriksson@berkeley.edu (Karen Eriksson)
Newsgroups: comp.sys.m68k
Subject: Discussion: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Mar18.075534.6922@berkeley.edu>
Date: Sat, 18 Mar 1995 07:55:34 GMT
Organization: UC Berkeley Department of EECS
NNTP-Posting-Host: berkeley.edu
X-Newsreader: Netscape 1.1N
Lines: 10

Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.

CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit.
At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII.

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

-- 
Karen Eriksson
Tape trading list upon request. SASE required for international mail.

From dmacdonald@ox.ac.uk Sun Mar 19 15:56:34 1995
Path: ashpoly!cascade!transat!ukc!fennimore!ox!dmacdonald
From: dmacdonald@ox.ac.uk (Dmitri MacDonald)
Newsgroups: comp.sys.m68k
Subject: Re: Discussion: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Mar19.155634.9282@ox.ac.uk>
Date: Sun, 19 Mar 1995 15:56:34 GMT
References: <1995Mar18.075534.6922@berkeley.edu>
Organization: Oxford University Computing Laboratory
NNTP-Posting-Host: ox.ac.uk
X-Newsreader: TIN [version 1.2 PL2]
Lines: 10

In article <1995Mar18.075534.6922@berkeley.edu>, keriksson@berkeley.edu (Karen Eriksson) writes:
> Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.
> CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit.

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

-- 
Dmitri MacDonald
Opinions expressed are solely my own and not those of Oxford University Computing Laboratory.
------------------------------------------------------------

From msilva@pipeline.com Mon Mar 20 19:58:34 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!pipeline!msilva
From: msilva@pipeline.com (Morag Silva)
Newsgroups: comp.sys.m68k
Subject: Re: Discussion: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1995Mar20.195834.4522@pipeline.com>
Date: Mon, 20 Mar 1995 19:58:34 GMT
References: <1995Mar18.075534.6922@berkeley.edu> <1995Mar19.155634.9282@ox.ac.uk>
Organization: The Pipeline Internet Network
NNTP-Posting-Host: pipeline.com
X-Newsreader: NewsWatcher 2.0b24
Lines: 8

In article <1995Mar19.155634.9282@ox.ac.uk>, dmacdonald@ox.ac.uk (Dmitri MacDonald) writes:
> The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon.

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

-- 
Morag Silva
Tape trading list upon request. SASE required for international mail.