From lmuller@unam.mx Wed Jan 10 07:33:43 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!unam!lmuller From: lmuller@unam.mx (Lucia Müller) Newsgroups: comp.sys.m68k Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Jan10.073343.5096@unam.mx> Date: Wed, 10 Jan 1996 07:33:43 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 11 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? -- Lucia Müller | lmuller@unam.mx PGP Key fingerprint: BC52 FE3B 2E60 EFBE "Keep the channels open." From periksson@purdue.edu Thu Jan 11 00:39:43 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!purdue!periksson From: periksson@purdue.edu (Pavel Eriksson) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Jan11.003943.9980@purdue.edu> Date: Thu, 11 Jan 1996 00:39:43 GMT References: <1996Jan10.073343.5096@unam.mx> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1996Jan10.073343.5096@unam.mx>, lmuller@unam.mx (Lucia Müller) 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. If you are posting from AOL, please read RFC 1036 before posting again. -- Pavel Eriksson "We don't sign stars. We build them." 486DX4/100 (FreeBSD 2.0.5) / SunOS 4.1.4 From abrennan@mit.edu Fri Jan 12 15:11:43 1996 Path: ashpoly!cascade!transat!ukc!fennimore!mit!abrennan From: abrennan@mit.edu (Andrei Brennan) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Jan12.151143.2752@mit.edu> Date: Fri, 12 Jan 1996 15:11:43 GMT References: <1996Jan10.073343.5096@unam.mx> <1996Jan11.003943.9980@purdue.edu> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Jan11.003943.9980@purdue.edu>, periksson@purdue.edu (Pavel Eriksson) writes: > Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. -- === Andrei Brennan === Dept of Electrical Engineering, Massachusetts Institute of Technology "Extraordinary claims require extraordinary spectra."