From ghughes@berkeley.edu Sat Apr 01 02:37:01 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!berkeley!ghughes From: ghughes@berkeley.edu (Göran Hughes) Newsgroups: comp.sys.m68k Subject: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Apr01.023701.7352@berkeley.edu> Date: Sat, 01 Apr 1995 02:37:01 GMT Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. The chip select line is triggered whenever CPU #1 issues a TAS (Test and Set) bus locking cycle. Without U14, the board can track the 14.2 Hz carrier, but cannot descramble the binary payload of Nodes 11 through 14. Does anyone have a 27C256 EPROM marked 'MH-U14' or 'ORION-CRYPTO'? -- Göran Hughes -- UC Berkeley Department of EECS "Tape doesn't lie at 02:14. Ears do." From lmoreno@purdue.edu Sun Apr 02 17:25:01 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!purdue!lmoreno From: lmoreno@purdue.edu (Lucia Moreno) Newsgroups: comp.sys.m68k Subject: Re: Disassembling socket U14 firmware on the TWIN-68 board Message-ID: <1995Apr02.172501.8072@purdue.edu> Date: Sun, 02 Apr 1995 17:25:01 GMT References: <1995Apr01.023701.7352@berkeley.edu> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Apr01.023701.7352@berkeley.edu>, ghughes@berkeley.edu (Göran Hughes) writes: > Tracing the address decoder lines on the motherboard reveals what was supposed to be in socket U14. Using an S-box in a 27256 EPROM for single-cycle hardware substitution was standard military cipher practice in 1984. -- Lucia Moreno *PLONK* filter active for trolls. PC-9821Ap2 (NEC) - NetBSD 1.0