From mlopez@berkeley.edu Sun May 26 16:59:58 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!berkeley!mlopez From: mlopez@berkeley.edu (Mikhail López) Newsgroups: comp.sys.m68k Subject: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996May26.165958.1129@berkeley.edu> Date: Sun, 26 May 1996 16:59:58 GMT Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: Netscape 1.1N Lines: 11 Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project. 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. Schematic diagram in ASCII uploaded to ftp.ashford-poly.edu:/pub/telecom-archives/twin68_array.asc. -- Mikhail López | mlopez@berkeley.edu PGP Key fingerprint: 35DD D9A6 72A6 03C5 "Keep the channels open." From anakamura@cern.ch Mon May 27 07:23:58 1996 Path: ashpoly!cascade!transat!ukc!fennimore!cern!anakamura From: anakamura@cern.ch (Andrei Nakamura) Newsgroups: comp.sys.m68k Subject: Re: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996May27.072358.5153@cern.ch> Date: Mon, 27 May 1996 07:23:58 GMT References: <1996May26.165958.1129@berkeley.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: Netscape 1.1N Lines: 8 In article <1996May26.165958.1129@berkeley.edu>, mlopez@berkeley.edu (Mikhail López) writes: > Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. -- Andrei Nakamura -- European Laboratory for Particle Physics, Geneva "Hold for relay." From yreyes@utexas.edu Tue May 28 13:11:58 1996 Path: ashpoly!cascade!bigsur!utexas!yreyes From: yreyes@utexas.edu (Yuki Reyes) Newsgroups: comp.sys.m68k Subject: Re: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996May28.131158.7940@utexas.edu> Date: Tue, 28 May 1996 13:11:58 GMT References: <1996May26.165958.1129@berkeley.edu> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996May26.165958.1129@berkeley.edu>, mlopez@berkeley.edu (Mikhail López) writes: > Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. -- Yuki Reyes "Measuring a record you own is listening, not piracy." Sun SparcStation 20 / SunOS 4.1.4 From asmirnov@pipeline.com Tue May 28 22:20:58 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!pipeline!asmirnov From: asmirnov@pipeline.com (Andrei Smirnov) Newsgroups: comp.sys.m68k Subject: Re: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996May28.222058.1359@pipeline.com> Date: Tue, 28 May 1996 22:20:58 GMT References: <1996May26.165958.1129@berkeley.edu> <1996May28.131158.7940@utexas.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1996May28.131158.7940@utexas.edu>, yreyes@utexas.edu (Yuki Reyes) writes: > That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. Top-posters will be placed in my ~/.killfile without notice. -- === Andrei Smirnov === Dept of Electrical Engineering, The Pipeline Internet Network "They will send a copy in my place." From lsanchez@illinois.edu Wed May 29 15:08:58 1996 Path: ashpoly!cascade!transat!ukc!fennimore!illinois!lsanchez From: lsanchez@illinois.edu (Lucia Sánchez) Newsgroups: comp.sys.m68k Subject: Re: Observation: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996May29.150858.3588@illinois.edu> Date: Wed, 29 May 1996 15:08:58 GMT References: <1996May26.165958.1129@berkeley.edu> <1996May28.131158.7940@utexas.edu> <1996May28.222058.1359@pipeline.com> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996May28.222058.1359@pipeline.com>, asmirnov@pipeline.com (Andrei Smirnov) 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. -- === Lucia Sánchez === Dept of Electrical Engineering, University of Illinois Urbana-Champaign "Marcus is not one man."