From mokonkwo@ox.ac.uk Sat Mar 02 08:02:21 1996
Path: ashpoly!bigsur!pacrim!jpgate!kamome!ox!mokonkwo
From: mokonkwo@ox.ac.uk (Mikhail Okonkwo)
Newsgroups: comp.sys.m68k
Subject: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Mar02.080221.4497@ox.ac.uk>
Date: Sat, 02 Mar 1996 08:02:21 GMT
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Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project.

Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.
At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII.

One 28-pin EPROM socket (labeled U14) is completely empty. What firmware was supposed to be in that socket?

-- 
Mikhail Okonkwo | mokonkwo@ox.ac.uk
PGP Key fingerprint: 9744 0C37 264B F40E
"Keep the channels open."

From thughes@ox.ac.uk Sat Mar 02 15:37:21 1996
Path: ashpoly!cascade!transat!eunet-de!hansebox!ox!thughes
From: thughes@ox.ac.uk (Thiago Hughes)
Newsgroups: comp.sys.m68k
Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Mar02.153721.8934@ox.ac.uk>
Date: Sat, 02 Mar 1996 15:37:21 GMT
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In article <1996Mar02.080221.4497@ox.ac.uk>, mokonkwo@ox.ac.uk (Mikhail Okonkwo) writes:
> Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project.

Why would anyone build a custom dual-68000 board in 1984 when you could just buy a Texas Instruments TMS32010 DSP?

-- 
Thiago Hughes
Opinions expressed are solely my own and not those of Oxford University Computing Laboratory.
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From hlopez@kiae.su Mon Mar 04 03:49:21 1996
Path: ashpoly!cascade!transat!sunet!nordrelay!kiae!hlopez
From: hlopez@kiae.su (Hugo López)
Newsgroups: comp.sys.m68k
Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Mar04.034921.5379@kiae.su>
Date: Mon, 04 Mar 1996 03:49:21 GMT
References: <1996Mar02.080221.4497@ox.ac.uk>
Organization: Kurchatov Institute of Atomic Energy, Moscow
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In article <1996Mar02.080221.4497@ox.ac.uk>, mokonkwo@ox.ac.uk (Mikhail Okonkwo) writes:
> Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project.
> Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'.

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

-- 
Hugo López | hlopez@kiae.su
PGP Key fingerprint: AA31 DB3C 2132 B83A
"Keep the channels open."

From lchoi@kiae.su Mon Mar 04 22:55:21 1996
Path: ashpoly!cascade!mxgate!coyoacan!kiae!lchoi
From: lchoi@kiae.su (Liam Choi)
Newsgroups: comp.sys.m68k
Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump
Message-ID: <1996Mar04.225521.2978@kiae.su>
Date: Mon, 04 Mar 1996 22:55:21 GMT
References: <1996Mar02.080221.4497@ox.ac.uk> <1996Mar04.034921.5379@kiae.su>
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In article <1996Mar04.034921.5379@kiae.su>, hlopez@kiae.su (Hugo López) writes:
> The TMS32010 had severe memory limitations in 1984 (only 144 words of on-chip RAM). Dual 68000s gave them full 16MB address space.

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

-- 
Liam Choi
Opinions expressed are solely my own and not those of Kurchatov Institute of Atomic Energy, Moscow.
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