From gwatanabe@ox.ac.uk Thu Mar 21 03:38:02 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!ox!gwatanabe From: gwatanabe@ox.ac.uk (Göran Watanabe) Newsgroups: comp.sys.m68k Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Mar21.033802.5453@ox.ac.uk> Date: Thu, 21 Mar 1996 03:38:02 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 11 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'. CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit. One 28-pin EPROM socket (labeled U14) is completely empty. What firmware was supposed to be in that socket? -- Göran Watanabe US Robotics Courier V.34 @ 9600 Telebit bps "They will send a copy in my place." From mrobertson@mindspring.com Thu Mar 21 17:01:02 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!mindspring!mrobertson From: mrobertson@mindspring.com (Marta Robertson) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Mar21.170102.7317@mindspring.com> Date: Thu, 21 Mar 1996 17:01:02 GMT References: <1996Mar21.033802.5453@ox.ac.uk> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Mar21.033802.5453@ox.ac.uk>, gwatanabe@ox.ac.uk (Göran Watanabe) 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'. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. -- Marta Robertson | mrobertson@mindspring.com PGP Key fingerprint: C012 1D5C DB73 A39B "Keep the channels open." From hweber@purdue.edu Fri Mar 22 09:25:02 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!purdue!hweber From: hweber@purdue.edu (Hana Weber) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Mar22.092502.2373@purdue.edu> Date: Fri, 22 Mar 1996 09:25:02 GMT References: <1996Mar21.033802.5453@ox.ac.uk> <1996Mar21.170102.7317@mindspring.com> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: Netscape 1.1N Lines: 11 In article <1996Mar21.170102.7317@mindspring.com>, mrobertson@mindspring.com (Marta Robertson) writes: > That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Hana Weber US Robotics Courier V.34 @ 28,800 bps "A soul is not exclusive to biology." From jweber@u-tokyo.ac.jp Fri Mar 22 23:04:02 1996 Path: ashpoly!cascade!brgate!saturno!u-tokyo!jweber From: jweber@u-tokyo.ac.jp (Ji-woo Weber) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Mar22.230402.8606@u-tokyo.ac.jp> Date: Fri, 22 Mar 1996 23:04:02 GMT References: <1996Mar21.033802.5453@ox.ac.uk> <1996Mar21.170102.7317@mindspring.com> <1996Mar22.092502.2373@purdue.edu> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Mar22.092502.2373@purdue.edu>, hweber@purdue.edu (Hana Weber) writes: > The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon. > Unsubscribe me from this list! (Wait, this is Usenet, never mind). Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. -- Ji-woo Weber "They will send a copy in my place." Atari TT030 / NEXTSTEP 3.3 From achoi@netcom.com Sun Mar 24 13:00:02 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!netcom!achoi From: achoi@netcom.com (Anja Choi) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Mar24.130002.9893@netcom.com> Date: Sun, 24 Mar 1996 13:00:02 GMT References: <1996Mar21.033802.5453@ox.ac.uk> <1996Mar21.170102.7317@mindspring.com> <1996Mar22.092502.2373@purdue.edu> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1996Mar22.092502.2373@purdue.edu>, hweber@purdue.edu (Hana Weber) writes: > The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon. > Unsubscribe me from this list! (Wait, this is Usenet, never mind). 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. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Anja Choi | achoi@netcom.com PGP Key fingerprint: A62D A405 A51D CC54 "Keep the channels open."