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Xref: sserve comp.os.386bsd.development:1738 comp.unix.bsd:13344 Newsgroups: comp.os.386bsd.development,comp.unix.bsd Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!decwrl!decwrl!netcomsv!netcom.com!jmonroy From: jmonroy@netcom.com (Jesus Monroy Jr) Subject: Re: Late comments on the DMA problem. Message-ID: <jmonroyCKB7oF.4MF@netcom.com> Organization: NETCOM On-line Communication Services (408 241-9760 guest) X-Newsreader: TIN [version 1.2 PL1] References: <jmonroyCJy610.HB7@netcom.com> <1994Jan21.095505.8375@cc.usu.edu> <jmonroyCK2t6n.1pM@netcom.com> <1994Jan24.103912.8591@cc.usu.edu> <jmonroyCK6o70.4B5@netcom.com> <1994Jan26.100319.8869@cc.usu.edu> Date: Thu, 27 Jan 1994 22:26:38 GMT Lines: 31 ivie@cc.usu.edu wrote: : In article <jmonroyCK6o70.4B5@netcom.com>, jmonroy@netcom.com (Jesus Monroy Jr) writes: : > ivie@cc.usu.edu wrote: : > : Page = virtual memory page. I'm most familiar with the VAX, where a page : > : is 512 bytes; I don't know how big it is on these newfangled 386 thingies. : > : : > a memory page is not defined well, but I beleive (if memory serves) : > a memory page for MS-DOS is 512 bytes. : Since MS-DOS doesn't run in virtual memory, you don't need to do : scatter/gather for it. : please don't start a tangent on this discussion. If you want to start about MS-DOS's problems, please start a new thread... Thank you. : > As for an interrupt, the FDC does interrupt when the I/O : > transaction is complete. So maybe this negates your : > comments, which are still a bit ambiguous. : If all of your transactions are complete without crossing page boundaries, : you also don't need to do scatter/gather. ; Can we please stick to the DMA problem? Please. -- Jesus Monroy Jr jmonroy@netcom.com Zebra Research /386BSD/device-drivers /fd /qic /clock /documentation ___________________________________________________________________________