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Xref: sserve comp.os.386bsd.development:1729 comp.unix.bsd:13334 Path: sserve!newshost.anu.edu.au!munnari.oz.au!bunyip.cc.uq.oz.au!harbinger.cc.monash.edu.au!yeshua.marcam.com!news.kei.com!eff!usenet.ins.cwru.edu!howland.reston.ans.net!cs.utexas.edu!sdd.hp.com!col.hp.com!csn!hellgate.utah.edu!cc.usu.edu!ivie From: ivie@cc.usu.edu Newsgroups: comp.os.386bsd.development,comp.unix.bsd Subject: Re: Late comments on the DMA problem. Message-ID: <1994Jan26.100319.8869@cc.usu.edu> Date: 26 Jan 94 10:03:19 MDT 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> Followup-To: comp.os.386bsd.development,comp.unix.bsd Organization: Utah State University Lines: 21 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. > > 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. -- ----------------+------------------------------------------------------ Roger Ivie | Don't think of it as a 'new' computer, think of it as ivie@cc.usu.edu | 'obsolete-ready'