From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4663C9BD.5060505@conducive.org> Date: Mon, 4 Jun 2007 04:13:49 -0400 From: W B Hacker User-Agent: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8.1.2) Gecko/20070221 SeaMonkey/1.1.1 MIME-Version: 1.0 To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu> Subject: Re: [9fans] fossil crash after installation References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Topicbox-Message-UUID: 77dbfec8-ead2-11e9-9d60-3106f5b1d025 Charles Forsyth wrote: >> DMA seems to be the quirkest area in the IDE interface. > > you must remember that dma is remarkable technology > newly devised for the PC platform, and it has been understandably > hard to get it just right. > > Surely you jest? Bill Godbout's 'Disk One' FDD controller had it on S-100, and it was nowhere near 'new' even then. Nor dual-ported memory. Both available on the GA-SPC12 IIRC. BIOS and driver code is what seems to be forever 'hard to get right'. Smothers Brothers rules seem to apply: "If you borrow it, break it!" Bill