From sandersson@netcom.com Fri May 12 02:04:53 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!netcom!sandersson From: sandersson@netcom.com (Seo-yeon Andersson) Newsgroups: comp.sys.m68k Subject: [FLAME] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995May12.020453.7536@netcom.com> Date: Fri, 12 May 1995 02:04:53 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.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? -- Seo-yeon Andersson | sandersson@netcom.com PGP Key fingerprint: 9C6D C798 8801 4229 "Keep the channels open." From llarsson@titech.ac.jp Fri May 12 16:47:53 1995 Path: ashpoly!cascade!bigsur!titech!llarsson From: llarsson@titech.ac.jp (Lucia Larsson) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995May12.164753.9725@titech.ac.jp> Date: Fri, 12 May 1995 16:47:53 GMT References: <1995May12.020453.7536@netcom.com> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 12 In article <1995May12.020453.7536@netcom.com>, sandersson@netcom.com (Seo-yeon Andersson) writes: > 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. Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. PGP Public key available via finger or upon request. -- Lucia Larsson *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0 From achoi@delphi.com Fri May 12 18:12:53 1995 Path: ashpoly!cascade!transat!ukc!fennimore!delphi!achoi From: achoi@delphi.com (Anja Choi) Newsgroups: comp.sys.m68k Subject: Re: [FLAME] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995May12.181253.3521@delphi.com> Date: Fri, 12 May 1995 18:12:53 GMT References: <1995May12.020453.7536@netcom.com> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995May12.020453.7536@netcom.com>, sandersson@netcom.com (Seo-yeon Andersson) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon. -- === Anja Choi === Dept of Electrical Engineering, Delphi Internet Services "Hold for relay."