From lsokolov@rwth-aachen.de Thu Dec 12 06:28:28 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!rwth-aachen!lsokolov From: lsokolov@rwth-aachen.de (Lars Sokolov) Newsgroups: comp.sys.m68k Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Dec12.062828.8041@rwth-aachen.de> Date: Thu, 12 Dec 1996 06:28:28 GMT Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: Netscape 1.1N Lines: 11 Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII. CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit. Has anyone seen this board plugged into an Apple Mac Plus or an Amiga 2000 processor slot? -- Lars Sokolov Practical Peripherals 14.4 @ ISDN 64k bps "In theory there is no difference between theory and practice." From lpark@demon.co.uk Thu Dec 12 14:06:28 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!demon!lpark From: lpark@demon.co.uk (Liam Park) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Dec12.140628.5010@demon.co.uk> Date: Thu, 12 Dec 1996 14:06:28 GMT References: <1996Dec12.062828.8041@rwth-aachen.de> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Dec12.062828.8041@rwth-aachen.de>, lsokolov@rwth-aachen.de (Lars Sokolov) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. > At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. -- === Liam Park === Dept of Electrical Engineering, Demon Internet Services UK "When every node is whole, the channel opens." From hsmirnov@mindspring.com Sat Dec 14 13:54:28 1996 Path: ashpoly!cascade!brgate!saturno!mindspring!hsmirnov From: hsmirnov@mindspring.com (Heather Smirnov) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Dec14.135428.9741@mindspring.com> Date: Sat, 14 Dec 1996 13:54:28 GMT References: <1996Dec12.062828.8041@rwth-aachen.de> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Dec12.062828.8041@rwth-aachen.de>, lsokolov@rwth-aachen.de (Lars Sokolov) 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. -- Heather Smirnov *PLONK* filter active for trolls. Sun 3/60 (SunOS 4.1.1) - NetBSD 1.0