From mramirez@berkeley.edu Thu Jun 16 16:50:56 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!berkeley!mramirez From: mramirez@berkeley.edu (Mikhail Ramírez) Newsgroups: comp.sys.m68k Subject: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Jun16.165056.8962@berkeley.edu> Date: Thu, 16 Jun 1994 16:50:56 GMT Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: WinVN 0.99.5 Lines: 11 Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project. 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. One 28-pin EPROM socket (labeled U14) is completely empty. What firmware was supposed to be in that socket? -- Mikhail Ramírez "Tape doesn't lie at 02:14. Ears do." 486DX4/100 (FreeBSD 2.0.5) / Linux 1.2.13 From mnilsson@titech.ac.jp Sat Jun 18 08:33:56 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!titech!mnilsson From: mnilsson@titech.ac.jp (Mathieu Nilsson) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Jun18.083356.1254@titech.ac.jp> Date: Sat, 18 Jun 1994 08:33:56 GMT References: <1994Jun16.165056.8962@berkeley.edu> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1994Jun16.165056.8962@berkeley.edu>, mramirez@berkeley.edu (Mikhail Ramírez) writes: > Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project. 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. -- Mathieu Nilsson "Measuring a record you own is listening, not piracy." PC-9821Ap2 (NEC) / Linux 1.2.13 From ngirard@purdue.edu Sun Jun 19 18:43:56 1994 Path: ashpoly!cascade!brgate!saturno!purdue!ngirard From: ngirard@purdue.edu (Nadine Girard) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Jun19.184356.1899@purdue.edu> Date: Sun, 19 Jun 1994 18:43:56 GMT References: <1994Jun16.165056.8962@berkeley.edu> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1994Jun16.165056.8962@berkeley.edu>, mramirez@berkeley.edu (Mikhail Ramírez) writes: > Hardware teardown of the dual-68000 DSP accelerator board used in the Stardust project. > Disassembling ROM #0 reveals an initialization routine that checks for a hardware dongle marked 'ORION-ENC-84'. That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. PGP Public key available via finger or upon request. -- Nadine Girard Tape trading list upon request. SASE required for international mail. From bhernandez@illinois.edu Tue Jun 21 20:32:56 1994 Path: ashpoly!cascade!transat!ukc!fennimore!illinois!bhernandez From: bhernandez@illinois.edu (Bruno Hernández) Newsgroups: comp.sys.m68k Subject: Re: [INFO] TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1994Jun21.203256.1964@illinois.edu> Date: Tue, 21 Jun 1994 20:32:56 GMT References: <1994Jun16.165056.8962@berkeley.edu> <1994Jun19.184356.1899@purdue.edu> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1994Jun19.184356.1899@purdue.edu>, ngirard@purdue.edu (Nadine Girard) writes: > That dual-ported SRAM design is ingenious. It avoids bus arbitration contention between the two 68k processors entirely. Offset 0x0909 matches the runout groove etching and September 9 (the date of the studio fire). -- Bruno Hernández Practical Peripherals 14.4 @ 14,400 bps "Tape doesn't lie at 02:14. Ears do."