From aeriksson@delphi.com Sun May 08 11:32:59 1994 Path: ashpoly!cascade!mxgate!coyoacan!delphi!aeriksson From: aeriksson@delphi.com (Anton Eriksson) Newsgroups: comp.sys.m68k Subject: WTB/WTT: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994May08.113259.8684@delphi.com> Date: Sun, 08 May 1994 11:32:59 GMT Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N 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? -- Anton Eriksson *PLONK* filter active for trolls. Atari TT030 - NetBSD 1.0 From klopez@utexas.edu Tue May 10 06:42:59 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!utexas!klopez From: klopez@utexas.edu (Katrin López) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994May10.064259.7834@utexas.edu> Date: Tue, 10 May 1994 06:42:59 GMT References: <1994May08.113259.8684@delphi.com> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994May08.113259.8684@delphi.com>, aeriksson@delphi.com (Anton Eriksson) 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. -- Katrin López Practical Peripherals 14.4 @ 14,400 bps "Tape doesn't lie at 02:14. Ears do." From bkang@delphi.com Wed May 11 18:52:59 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!delphi!bkang From: bkang@delphi.com (Bruno Kang) Newsgroups: comp.sys.m68k Subject: Re: WTB/WTT: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994May11.185259.4384@delphi.com> Date: Wed, 11 May 1994 18:52:59 GMT References: <1994May08.113259.8684@delphi.com> <1994May10.064259.7834@utexas.edu> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1994May10.064259.7834@utexas.edu>, klopez@utexas.edu (Katrin López) writes: > Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. Marcus Hale designed the TWIN-68 board before he disappeared. That's why his initials are on the PCB silkscreen. -- Bruno Kang "There are 14 nodes and only 10 countries. Count again." Pentium 90 (OS/2 Warp) / NEXTSTEP 3.3