From fsato@netcom.com Sun May 15 18:25:19 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!netcom!fsato From: fsato@netcom.com (Freya Sato) Newsgroups: comp.sys.m68k Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994May15.182519.8410@netcom.com> Date: Sun, 15 May 1994 18:25:19 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com 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. Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'. Schematic diagram in ASCII uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/twin68_array.asc. -- Freya Sato "The carrier frequency does not drift by accident." Amiga 1200 (Blizzard 030/50) / TOS 4.04 From bdubois@mit.edu Mon May 16 04:04:19 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!mit!bdubois From: bdubois@mit.edu (Bruno Dubois) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994May16.040419.3001@mit.edu> Date: Mon, 16 May 1994 04:04:19 GMT References: <1994May15.182519.8410@netcom.com> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1994May15.182519.8410@netcom.com>, fsato@netcom.com (Freya Sato) writes: > 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. Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. -- Bruno Dubois Opinions expressed are solely my own and not those of Massachusetts Institute of Technology. ------------------------------------------------------------ From jramirez@pacbell.net Tue May 17 01:43:19 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!pacbell!jramirez From: jramirez@pacbell.net (Joachim Ramírez) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994May17.014319.4608@pacbell.net> Date: Tue, 17 May 1994 01:43:19 GMT References: <1994May15.182519.8410@netcom.com> <1994May16.040419.3001@mit.edu> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: Netscape 1.1N Lines: 9 In article <1994May16.040419.3001@mit.edu>, bdubois@mit.edu (Bruno Dubois) 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. -- Joachim Ramírez "The carrier frequency does not drift by accident." Atari TT030 / SunOS 4.1.4 From bfournier@purdue.edu Tue May 17 04:58:19 1994 Path: ashpoly!cascade!transat!ukc!fennimore!purdue!bfournier From: bfournier@purdue.edu (Bastien Fournier) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994May17.045819.7700@purdue.edu> Date: Tue, 17 May 1994 04:58:19 GMT References: <1994May15.182519.8410@netcom.com> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: Netscape 1.1N Lines: 8 In article <1994May15.182519.8410@netcom.com>, fsato@netcom.com (Freya Sato) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. Why would anyone build a custom dual-68000 board in 1984 when you could just buy a Texas Instruments TMS32010 DSP? -- Bastien Fournier Tape trading list upon request. SASE required for international mail.