From ywatanabe@pacbell.net Tue Jun 06 00:19:09 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!pacbell!ywatanabe From: ywatanabe@pacbell.net (Yuki Watanabe) Newsgroups: comp.sys.m68k Subject: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Jun06.001909.9228@pacbell.net> Date: Tue, 06 Jun 1995 00:19:09 GMT Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net 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. 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. One 28-pin EPROM socket (labeled U14) is completely empty. What firmware was supposed to be in that socket? -- Yuki Watanabe *PLONK* filter active for trolls. Mac IIci / 68882 FPU - NetBSD 1.0 From hlee@kiae.su Wed Jun 07 16:18:09 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!kiae!hlee From: hlee@kiae.su (Hugo Lee) Newsgroups: comp.sys.m68k Subject: Re: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Jun07.161809.2680@kiae.su> Date: Wed, 07 Jun 1995 16:18:09 GMT References: <1995Jun06.001909.9228@pacbell.net> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Jun06.001909.9228@pacbell.net>, ywatanabe@pacbell.net (Yuki Watanabe) 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. -- Hugo Lee *PLONK* filter active for trolls. Sun SparcStation 20 - NetBSD 1.0 From jpetrov@pacbell.net Thu Jun 08 18:46:09 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!pacbell!jpetrov From: jpetrov@pacbell.net (Joachim Petrov) Newsgroups: comp.sys.m68k Subject: Re: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Jun08.184609.1301@pacbell.net> Date: Thu, 08 Jun 1995 18:46:09 GMT References: <1995Jun06.001909.9228@pacbell.net> <1995Jun07.161809.2680@kiae.su> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1995Jun07.161809.2680@kiae.su>, hlee@kiae.su (Hugo Lee) writes: > Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. Looks like a prototype telecommunications board for military secure voice, not an audio music product. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Joachim Petrov Opinions expressed are solely my own and not those of Pacific Bell Internet Services. ------------------------------------------------------------ From mnakamura@purdue.edu Sat Jun 10 03:00:09 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!purdue!mnakamura From: mnakamura@purdue.edu (Mei Nakamura) Newsgroups: comp.sys.m68k Subject: Re: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Jun10.030009.9914@purdue.edu> Date: Sat, 10 Jun 1995 03:00:09 GMT References: <1995Jun06.001909.9228@pacbell.net> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Jun06.001909.9228@pacbell.net>, ywatanabe@pacbell.net (Yuki Watanabe) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. -- Mei Nakamura Zyxel U-1496E @ 14,400 bps "Hardware is temporary. The signal survives." From mkowalski@pipeline.com Sat Jun 10 08:03:09 1995 Path: ashpoly!cascade!mxgate!coyoacan!pipeline!mkowalski From: mkowalski@pipeline.com (Morag Kowalski) Newsgroups: comp.sys.m68k Subject: Re: Data: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Jun10.080309.5439@pipeline.com> Date: Sat, 10 Jun 1995 08:03:09 GMT References: <1995Jun06.001909.9228@pacbell.net> <1995Jun10.030009.9914@purdue.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1995Jun10.030009.9914@purdue.edu>, mnakamura@purdue.edu (Mei Nakamura) 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. -- Morag Kowalski Tape trading list upon request. SASE required for international mail.