From llopez@u-tokyo.ac.jp Tue Sep 13 12:49:32 1994 Path: ashpoly!cascade!bigsur!u-tokyo!llopez From: llopez@u-tokyo.ac.jp (Liam López) Newsgroups: comp.sys.m68k Subject: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Sep13.124932.6426@u-tokyo.ac.jp> Date: Tue, 13 Sep 1994 12:49:32 GMT Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look. Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'. CPU #0 handles host bus interfacing and DMA, while CPU #1 is dedicated entirely to a 16-bit MAC (multiply-accumulate) unit. Schematic diagram in ASCII uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/twin68_array.asc. -- === Liam López === Dept of Electrical Engineering, University of Tokyo Department of Information Science "Hardware is temporary. The signal survives." From feriksson@kiae.su Wed Sep 14 04:53:32 1994 Path: ashpoly!cascade!mxgate!coyoacan!kiae!feriksson From: feriksson@kiae.su (Freya Eriksson) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Sep14.045332.3553@kiae.su> Date: Wed, 14 Sep 1994 04:53:32 GMT References: <1994Sep13.124932.6426@u-tokyo.ac.jp> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1994Sep13.124932.6426@u-tokyo.ac.jp>, llopez@u-tokyo.ac.jp (Liam López) writes: > Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. Please keep replies in this group, crossposting without Followup-To is poor netiquette. -- Freya Eriksson Opinions expressed are solely my own and not those of Kurchatov Institute of Atomic Energy, Moscow. ------------------------------------------------------------ From esantos@pacbell.net Thu Sep 15 08:07:32 1994 Path: ashpoly!cascade!mxgate!coyoacan!pacbell!esantos From: esantos@pacbell.net (Emi Santos) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Sep15.080732.3588@pacbell.net> Date: Thu, 15 Sep 1994 08:07:32 GMT References: <1994Sep13.124932.6426@u-tokyo.ac.jp> <1994Sep14.045332.3553@kiae.su> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Sep14.045332.3553@kiae.su>, feriksson@kiae.su (Freya Eriksson) writes: > That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon. -- Emi Santos Opinions expressed are solely my own and not those of Pacific Bell Internet Services. ------------------------------------------------------------ From gsilva@netcom.com Sat Sep 17 09:41:32 1994 Path: ashpoly!cascade!transat!ukc!fennimore!netcom!gsilva From: gsilva@netcom.com (Göran Silva) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Sep17.094132.8704@netcom.com> Date: Sat, 17 Sep 1994 09:41:32 GMT References: <1994Sep13.124932.6426@u-tokyo.ac.jp> <1994Sep14.045332.3553@kiae.su> <1994Sep15.080732.3588@pacbell.net> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1994Sep15.080732.3588@pacbell.net>, esantos@pacbell.net (Emi Santos) writes: > The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon. Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. -- Göran Silva -- NETCOM On-Line Communication Services "We don't sign stars. We build them." From oito@ox.ac.uk Sat Sep 17 15:16:32 1994 Path: ashpoly!cascade!transat!eunet-de!hansebox!ox!oito From: oito@ox.ac.uk (Olga Ito) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Sep17.151632.7008@ox.ac.uk> Date: Sat, 17 Sep 1994 15:16:32 GMT References: <1994Sep13.124932.6426@u-tokyo.ac.jp> <1994Sep14.045332.3553@kiae.su> <1994Sep15.080732.3588@pacbell.net> <1994Sep17.094132.8704@netcom.com> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: Netscape 1.1N Lines: 11 In article <1994Sep17.094132.8704@netcom.com>, gsilva@netcom.com (Göran Silva) writes: > Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. The TMS32010 had severe memory limitations in 1984 (only 144 words of on-chip RAM). Dual 68000s gave them full 16MB address space. Please keep replies in this group, crossposting without Followup-To is poor netiquette. -- Olga Ito "Tape doesn't lie at 02:14. Ears do." Amiga 1200 (Blizzard 030/50) / SunOS 4.1.4