From akuznetsov@stanford.edu Tue May 16 04:56:05 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!stanford!akuznetsov From: akuznetsov@stanford.edu (Aiko Kuznetsov) Newsgroups: comp.sys.m68k Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995May16.045605.1991@stanford.edu> Date: Tue, 16 May 1995 04:56:05 GMT Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: Netscape 1.1N Lines: 10 Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit. 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? -- Aiko Kuznetsov Tape trading list upon request. SASE required for international mail. From bkuznetsov@cern.ch Wed May 17 10:01:05 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!cern!bkuznetsov From: bkuznetsov@cern.ch (Bruno Kuznetsov) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995May17.100105.8835@cern.ch> Date: Wed, 17 May 1995 10:01:05 GMT References: <1995May16.045605.1991@stanford.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1995May16.045605.1991@stanford.edu>, akuznetsov@stanford.edu (Aiko Kuznetsov) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. > CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. If you are posting from AOL, please read RFC 1036 before posting again. -- Bruno Kuznetsov "Extraordinary claims require extraordinary spectra." Macintosh IIfx / AmigaOS 3.1