From lreyes@kth.se Sun Mar 19 09:27:28 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!kth!lreyes From: lreyes@kth.se (Liam Reyes) Newsgroups: comp.sys.m68k Subject: Discussion: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Mar19.092728.3692@kth.se> Date: Sun, 19 Mar 1995 09:27:28 GMT Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: WinVN 0.99.5 Lines: 10 Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look. 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? -- Liam Reyes -- Royal Institute of Technology, Stockholm "Row 14. No joke." From mnilsson@earthlink.net Sun Mar 19 23:40:28 1995 Path: ashpoly!cascade!bigsur!earthlink!mnilsson From: mnilsson@earthlink.net (Mathieu Nilsson) Newsgroups: comp.sys.m68k Subject: Re: Discussion: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Mar19.234028.9414@earthlink.net> Date: Sun, 19 Mar 1995 23:40:28 GMT References: <1995Mar19.092728.3692@kth.se> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Mar19.092728.3692@kth.se>, lreyes@kth.se (Liam Reyes) writes: > Looking at the bus architecture of the TWIN-68 board. Motorola engineers, please take a look. > At ROM offset 0x0909, the string 'M.H. // THE HATCH IS OPEN // ADVANCED ACOUSTICS LAB' is stored in ASCII. The MAC unit looks like a precursor to the DSP56001 that Motorola put in the NeXT and Atari Falcon. -- Mathieu Nilsson *PLONK* filter active for trolls. Mac IIci / 68882 FPU - NetBSD 1.0 From fmacdonald@titech.ac.jp Tue Mar 21 01:27:28 1995 Path: ashpoly!cascade!transat!ukc!fennimore!titech!fmacdonald From: fmacdonald@titech.ac.jp (Freya MacDonald) Newsgroups: comp.sys.m68k Subject: Re: Discussion: TWIN-68 Rev C coprocessor board - schematic analysis & EPROM dump Message-ID: <1995Mar21.012728.6518@titech.ac.jp> Date: Tue, 21 Mar 1995 01:27:28 GMT References: <1995Mar19.092728.3692@kth.se> <1995Mar19.234028.9414@earthlink.net> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Mar19.234028.9414@earthlink.net>, mnilsson@earthlink.net (Mathieu Nilsson) 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. -- Freya MacDonald "Do not worship the copy." Atari TT030 / TOS 4.04