From probertson@purdue.edu Sun Jul 10 10:50:50 1994
Path: ashpoly!cascade!bigsur!purdue!probertson
From: probertson@purdue.edu (Pavel Robertson)
Newsgroups: comp.sys.m68k
Subject: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1994Jul10.105050.1955@purdue.edu>
Date: Sun, 10 Jul 1994 10:50:50 GMT
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Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.

At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII.
The board features two 68000 CPUs clocked at 12 MHz sharing a dual-ported 128KB static RAM bank.

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

-- 
=== Pavel Robertson ===
Dept of Electrical Engineering, Purdue University Engineering Computer Network
"Extraordinary claims require extraordinary spectra."

From agirard@uu.net Tue Jul 12 03:08:50 1994
Path: ashpoly!bigsur!pacrim!krgate!eunha!uu!agirard
From: agirard@uu.net (Anja Girard)
Newsgroups: comp.sys.m68k
Subject: Re: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1994Jul12.030850.5773@uu.net>
Date: Tue, 12 Jul 1994 03:08:50 GMT
References: <1994Jul10.105050.1955@purdue.edu>
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In article <1994Jul10.105050.1955@purdue.edu>, probertson@purdue.edu (Pavel Robertson) writes:
> Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly.
> At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII.

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

-- 
Anja Girard | agirard@uu.net
PGP Key fingerprint: 24DE 69FD 43F4 F78F
"Keep the channels open."