Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!zaphod.mps.ohio-state.edu!think!snorkelwacker!bloom-beacon!eru!luth!sunic!mcsun!ukc!dcl-cs!aber-cs!rupert!pcg From: pcg@rupert.cs.aber.ac.uk (Piercarlo Grandi) Newsgroups: comp.unix.i386 Subject: Re: SCSI and 386/ix Message-ID: Date: 5 Feb 90 19:07:11 GMT References: <25c1fdd8:490comp.unix.i386@nstar.UUCP> <1990Feb3.191842.1991@ddsw1.MCS.COM> Sender: pcg@aber-cs.UUCP Organization: Coleg Prifysgol Cymru Lines: 20 In-reply-to: karl@ddsw1.MCS.COM's message of 3 Feb 90 19:18:42 GMT In article <1990Feb3.191842.1991@ddsw1.MCS.COM> karl@ddsw1.MCS.COM (Karl Denninger) writes: [ ... about having dual WD1003 style controllers ... ] Even with ONE controller, it's not bad. ISC >will< overlap seeks to the two devices, IF your controller can handle it. If not, you have to turn off that feature in the space.c file for the device (it's on by default); this is the cause of some problmes with certain revisions of the WD1006 boards. This perplexes me. You sure that a WD1003 style controller can overlap seeks? Are there any that do? I can hardly imagine seeks not being synchronous to the controller with a WD1003 style controller, that must issue step pulses to the head. Are there really any RLL or MFM controllers (the WD1006 is by your implication) that can step independently the two arms? -- Piercarlo "Peter" Grandi | ARPA: pcg%cs.aber.ac.uk@nsfnet-relay.ac.uk Dept of CS, UCW Aberystwyth | UUCP: ...!mcvax!ukc!aber-cs!pcg Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@cs.aber.ac.uk