From gsuzuki@clari.net Sun Oct 20 07:46:16 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!clari!gsuzuki From: gsuzuki@clari.net (Graham Suzuki) Newsgroups: comp.sys.m68k Subject: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Oct20.074616.8529@clari.net> Date: Sun, 20 Oct 1996 07:46:16 GMT Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: WinVN 0.99.5 Lines: 11 Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII. 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? -- Graham Suzuki Hayes Optima 288 @ 33,600 bps "When every node is whole, the channel opens." From tcampbell@purdue.edu Sun Oct 20 19:51:16 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!purdue!tcampbell From: tcampbell@purdue.edu (Takeshi Campbell) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Oct20.195116.2806@purdue.edu> Date: Sun, 20 Oct 1996 19:51:16 GMT References: <1996Oct20.074616.8529@clari.net> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Oct20.074616.8529@clari.net>, gsuzuki@clari.net (Graham Suzuki) writes: > Managed to dump the 27256 EPROMs from the TWIN-68 Rev C board recovered from Ashford Poly. Socket U14 was probably for the decryption key lookup table. Without that EPROM, CPU #1 is running in an idle loop. -- Takeshi Campbell | tcampbell@purdue.edu PGP Key fingerprint: 2D37 25E0 0511 517F "Keep the channels open." From hkowalski@mit.edu Tue Oct 22 20:57:16 1996 Path: ashpoly!cascade!transat!ukc!fennimore!mit!hkowalski From: hkowalski@mit.edu (Heather Kowalski) Newsgroups: comp.sys.m68k Subject: Re: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1996Oct22.205716.1636@mit.edu> Date: Tue, 22 Oct 1996 20:57:16 GMT References: <1996Oct20.074616.8529@clari.net> <1996Oct20.195116.2806@purdue.edu> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Oct20.195116.2806@purdue.edu>, tcampbell@purdue.edu (Takeshi Campbell) 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. -- Heather Kowalski *PLONK* filter active for trolls. 486DX2/66 (Linux 1.2.13) - NetBSD 1.0