From nnakamura@cmu.edu Wed Nov 22 05:36:18 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!cmu!nnakamura From: nnakamura@cmu.edu (Nadine Nakamura) Newsgroups: comp.sys.m68k Subject: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Nov22.053618.5849@cmu.edu> Date: Wed, 22 Nov 1995 05:36:18 GMT Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: WinVN 0.99.5 Lines: 11 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. -- Nadine Nakamura Opinions expressed are solely my own and not those of Carnegie Mellon University School of CS. ------------------------------------------------------------ From mokonkwo@rwth-aachen.de Wed Nov 22 15:59:18 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!rwth-aachen!mokonkwo From: mokonkwo@rwth-aachen.de (Mike Okonkwo) Newsgroups: comp.sys.m68k Subject: Re: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Nov22.155918.1686@rwth-aachen.de> Date: Wed, 22 Nov 1995 15:59:18 GMT References: <1995Nov22.053618.5849@cmu.edu> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Nov22.053618.5849@cmu.edu>, nnakamura@cmu.edu (Nadine Nakamura) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. Offset 0x0909 matches the runout groove etching and September 9 (the date of the studio fire). -- Mike Okonkwo Zyxel U-1496E @ 14,400 bps "A soul is not exclusive to biology." From mpopov@illinois.edu Thu Nov 23 17:39:18 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!illinois!mpopov From: mpopov@illinois.edu (Mateo Popov) Newsgroups: comp.sys.m68k Subject: Re: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Nov23.173918.3654@illinois.edu> Date: Thu, 23 Nov 1995 17:39:18 GMT References: <1995Nov22.053618.5849@cmu.edu> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Nov22.053618.5849@cmu.edu>, nnakamura@cmu.edu (Nadine Nakamura) 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. -- Mateo Popov -- University of Illinois Urbana-Champaign "When every node is whole, the channel opens." From dkarlsson@uu.net Sat Nov 25 03:19:18 1995 Path: ashpoly!cascade!bigsur!uu!dkarlsson From: dkarlsson@uu.net (Dmitri Karlsson) Newsgroups: comp.sys.m68k Subject: Re: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Nov25.031918.6129@uu.net> Date: Sat, 25 Nov 1995 03:19:18 GMT References: <1995Nov22.053618.5849@cmu.edu> <1995Nov23.173918.3654@illinois.edu> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1995Nov23.173918.3654@illinois.edu>, mpopov@illinois.edu (Mateo Popov) writes: > That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. Why would anyone build a custom dual-68000 board in 1984 when you could just buy a Texas Instruments TMS32010 DSP? Top-posters will be placed in my ~/.killfile without notice. -- Dmitri Karlsson Practical Peripherals 14.4 @ ISDN 64k bps "5 sigma is a discovery. 7 is a question." From bsouza@cern.ch Sat Nov 25 15:47:18 1995 Path: ashpoly!cascade!brgate!saturno!cern!bsouza From: bsouza@cern.ch (Bastien Souza) Newsgroups: comp.sys.m68k Subject: Re: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Nov25.154718.8242@cern.ch> Date: Sat, 25 Nov 1995 15:47:18 GMT References: <1995Nov22.053618.5849@cmu.edu> <1995Nov22.155918.1686@rwth-aachen.de> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Nov22.155918.1686@rwth-aachen.de>, mokonkwo@rwth-aachen.de (Mike Okonkwo) writes: > Offset 0x0909 matches the runout groove etching and September 9 (the date of the studio fire). Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. -- Bastien Souza | bsouza@cern.ch PGP Key fingerprint: BB63 5F2A 83F0 EAF2 "Keep the channels open."