From ylee@earthlink.net Sat Sep 02 05:08:23 1995 Path: ashpoly!cascade!transat!ukc!fennimore!earthlink!ylee From: ylee@earthlink.net (Yuki Lee) Newsgroups: comp.sys.m68k Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Sep02.050823.8288@earthlink.net> Date: Sat, 02 Sep 1995 05:08:23 GMT Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: Netscape 1.1N 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. The board features two 68000 CPUs clocked at 12 MHz sharing a dual-ported 128KB static RAM bank. Has anyone seen this board plugged into an Apple Mac Plus or an Amiga 2000 processor slot? -- Yuki Lee *PLONK* filter active for trolls. Atari Falcon 030 - NetBSD 1.0 From klaurent@clari.net Sun Sep 03 20:50:23 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!clari!klaurent From: klaurent@clari.net (Katrin Laurent) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Sep03.205023.7696@clari.net> Date: Sun, 03 Sep 1995 20:50:23 GMT References: <1995Sep02.050823.8288@earthlink.net> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1995Sep02.050823.8288@earthlink.net>, ylee@earthlink.net (Yuki Lee) 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. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Katrin Laurent Opinions expressed are solely my own and not those of ClariNet Communications Corp. ------------------------------------------------------------ From mkowalski@panix.com Mon Sep 04 07:44:23 1995 Path: ashpoly!cascade!brgate!saturno!panix!mkowalski From: mkowalski@panix.com (Mateo Kowalski) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Sep04.074423.6946@panix.com> Date: Mon, 04 Sep 1995 07:44:23 GMT References: <1995Sep02.050823.8288@earthlink.net> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1995Sep02.050823.8288@earthlink.net>, ylee@earthlink.net (Yuki Lee) 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. -- Mateo Kowalski -- Public Access Unix of New York "We don't sign stars. We build them."