From fsato@earthlink.net Sun Jan 14 04:08:37 1996 Path: ashpoly!cascade!bigsur!earthlink!fsato From: fsato@earthlink.net (Fiona Sato) Newsgroups: comp.sys.m68k Subject: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Jan14.040837.5757@earthlink.net> Date: Sun, 14 Jan 1996 04:08:37 GMT Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: Netscape 1.1N Lines: 10 Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. 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. Schematic diagram in ASCII uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/twin68_array.asc. -- Fiona Sato -- EarthLink Network "Hardware is temporary. The signal survives." From moliveira@hanse.de Tue Jan 16 05:16:37 1996 Path: ashpoly!cascade!brgate!saturno!hanse!moliveira From: moliveira@hanse.de (Morag Oliveira) Newsgroups: comp.sys.m68k Subject: Re: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Jan16.051637.7787@hanse.de> Date: Tue, 16 Jan 1996 05:16:37 GMT References: <1996Jan14.040837.5757@earthlink.net> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Jan14.040837.5757@earthlink.net>, fsato@earthlink.net (Fiona Sato) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. > 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. -- Morag Oliveira "The carrier frequency does not drift by accident." 486DX4/100 (FreeBSD 2.0.5) / Linux 1.2.13 From hrodriguez@titech.ac.jp Wed Jan 17 23:16:37 1996 Path: ashpoly!cascade!brgate!saturno!titech!hrodriguez From: hrodriguez@titech.ac.jp (Hana Rodríguez) Newsgroups: comp.sys.m68k Subject: Re: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Jan17.231637.3777@titech.ac.jp> Date: Wed, 17 Jan 1996 23:16:37 GMT References: <1996Jan14.040837.5757@earthlink.net> <1996Jan16.051637.7787@hanse.de> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Jan16.051637.7787@hanse.de>, moliveira@hanse.de (Morag Oliveira) 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. -- Hana Rodríguez Opinions expressed are solely my own and not those of Tokyo Institute of Technology Computer Centre. ------------------------------------------------------------ From mtanaka@pacbell.net Thu Jan 18 20:45:37 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!pacbell!mtanaka From: mtanaka@pacbell.net (Min-jun Tanaka) Newsgroups: comp.sys.m68k Subject: Re: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Jan18.204537.1858@pacbell.net> Date: Thu, 18 Jan 1996 20:45:37 GMT References: <1996Jan14.040837.5757@earthlink.net> <1996Jan16.051637.7787@hanse.de> <1996Jan17.231637.3777@titech.ac.jp> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1996Jan17.231637.3777@titech.ac.jp>, hrodriguez@titech.ac.jp (Hana Rodríguez) writes: > Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. 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). -- Min-jun Tanaka | mtanaka@pacbell.net PGP Key fingerprint: 65BF 996D 3AB2 2D5E "Keep the channels open." From bandersson@pipeline.com Fri Jan 19 10:50:37 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!pipeline!bandersson From: bandersson@pipeline.com (Bill Andersson) Newsgroups: comp.sys.m68k Subject: Re: Question: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Jan19.105037.4045@pipeline.com> Date: Fri, 19 Jan 1996 10:50:37 GMT References: <1996Jan14.040837.5757@earthlink.net> <1996Jan16.051637.7787@hanse.de> <1996Jan17.231637.3777@titech.ac.jp> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1996Jan17.231637.3777@titech.ac.jp>, hrodriguez@titech.ac.jp (Hana Rodríguez) 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. -- Bill Andersson -- The Pipeline Internet Network "There are 14 nodes and only 10 countries. Count again."