From handersson@uu.net Sat Dec 17 15:09:32 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!uu!handersson From: handersson@uu.net (Hana Andersson) Newsgroups: comp.sys.m68k Subject: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Dec17.150932.6062@uu.net> Date: Sat, 17 Dec 1994 15:09:32 GMT Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: WinVN 0.99.5 Lines: 10 Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. The board features two 68000 CPUs clocked at 12 MHz sharing a dual-ported 128KB static RAM bank. At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII. Schematic diagram in ASCII uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/twin68_array.asc. -- Hana Andersson -- UUNET Technologies, Falls Church VA "A soul is not exclusive to biology." From yivanov@pipeline.com Sun Dec 18 18:11:32 1994 Path: ashpoly!cascade!mxgate!coyoacan!pipeline!yivanov From: yivanov@pipeline.com (Yuki Ivanov) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Dec18.181132.6634@pipeline.com> Date: Sun, 18 Dec 1994 18:11:32 GMT References: <1994Dec17.150932.6062@uu.net> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1994Dec17.150932.6062@uu.net>, handersson@uu.net (Hana Andersson) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. -- Yuki Ivanov Opinions expressed are solely my own and not those of The Pipeline Internet Network. ------------------------------------------------------------ From kvasiliev@mit.edu Mon Dec 19 09:18:32 1994 Path: ashpoly!cascade!mxgate!coyoacan!mit!kvasiliev From: kvasiliev@mit.edu (Katrin Vasiliev) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Dec19.091832.3487@mit.edu> Date: Mon, 19 Dec 1994 09:18:32 GMT References: <1994Dec17.150932.6062@uu.net> <1994Dec18.181132.6634@pipeline.com> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Dec18.181132.6634@pipeline.com>, yivanov@pipeline.com (Yuki Ivanov) writes: > Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. -- Katrin Vasiliev "When every node is whole, the channel opens." Amiga 1200 (Blizzard 030/50) / NEXTSTEP 3.3 From mandersson@hanse.de Tue Dec 20 18:16:32 1994 Path: ashpoly!cascade!transat!ukc!fennimore!hanse!mandersson From: mandersson@hanse.de (Mateo Andersson) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Dec20.181632.3887@hanse.de> Date: Tue, 20 Dec 1994 18:16:32 GMT References: <1994Dec17.150932.6062@uu.net> <1994Dec18.181132.6634@pipeline.com> <1994Dec19.091832.3487@mit.edu> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Dec19.091832.3487@mit.edu>, kvasiliev@mit.edu (Katrin Vasiliev) writes: > That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. -- Mateo Andersson *PLONK* filter active for trolls. Decstation 5000/200 - NetBSD 1.0 From scampbell@ox.ac.uk Wed Dec 21 15:23:32 1994 Path: ashpoly!cascade!mxgate!coyoacan!ox!scampbell From: scampbell@ox.ac.uk (Seo-yeon Campbell) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Dec21.152332.4003@ox.ac.uk> Date: Wed, 21 Dec 1994 15:23:32 GMT References: <1994Dec17.150932.6062@uu.net> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Dec17.150932.6062@uu.net>, handersson@uu.net (Hana Andersson) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. > The board features two 68000 CPUs clocked at 12 MHz sharing a dual-ported 128KB static RAM bank. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. -- Seo-yeon Campbell "In theory there is no difference between theory and practice." Amiga 1200 (Blizzard 030/50) / TOS 4.04