From dlindqvist@kiae.su Mon Apr 01 21:04:49 1996
Path: ashpoly!cascade!brgate!saturno!kiae!dlindqvist
From: dlindqvist@kiae.su (Diego Lindqvist)
Newsgroups: comp.sys.m68k
Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Apr01.210449.2433@kiae.su>
Date: Mon, 01 Apr 1996 21:04:49 GMT
Organization: Kurchatov Institute of Atomic Energy, Moscow
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Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.

Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.
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?

-- 
Diego Lindqvist
Opinions expressed are solely my own and not those of Kurchatov Institute of Atomic Energy, Moscow.
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From anakamura@earthlink.net Wed Apr 03 04:40:49 1996
Path: ashpoly!cascade!brgate!saturno!earthlink!anakamura
From: anakamura@earthlink.net (Astrid Nakamura)
Newsgroups: comp.sys.m68k
Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Apr03.044049.5356@earthlink.net>
Date: Wed, 03 Apr 1996 04:40:49 GMT
References: <1996Apr01.210449.2433@kiae.su>
Organization: EarthLink Network
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In article <1996Apr01.210449.2433@kiae.su>, dlindqvist@kiae.su (Diego Lindqvist) writes:
> Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look.
> Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.

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.

-- 
=== Astrid Nakamura ===
Dept of Electrical Engineering, EarthLink Network
"A soul is not exclusive to biology."

From mvasiliev@clari.net Thu Apr 04 17:52:49 1996
Path: ashpoly!cascade!transat!ukc!fennimore!clari!mvasiliev
From: mvasiliev@clari.net (Mike Vasiliev)
Newsgroups: comp.sys.m68k
Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Apr04.175249.9607@clari.net>
Date: Thu, 04 Apr 1996 17:52:49 GMT
References: <1996Apr01.210449.2433@kiae.su> <1996Apr03.044049.5356@earthlink.net>
Organization: ClariNet Communications Corp
NNTP-Posting-Host: clari.net
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In article <1996Apr03.044049.5356@earthlink.net>, anakamura@earthlink.net (Astrid Nakamura) 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.

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

-- 
=== Mike Vasiliev ===
Dept of Electrical Engineering, ClariNet Communications Corp
"The carrier frequency does not drift by accident."