Date: Wed, 22 Nov 1995 09:20:38 +0000 () From: Michael Smith <msmith@atrad.adelaide.edu.au> To: rb@gid.co.uk (Bob Bishop) Cc: msmith@atrad.adelaide.edu.au, hackers@freefall.freebsd.org Subject: Re: Anyone keen to help me get a Phillips CDD 521 Recorder working? Message-ID: <199511220920.JAA25560@genesis.atrad.adelaide.edu.au> In-Reply-To: <v01510100acd8946250dd@[194.32.164.2]> from "Bob Bishop" at Nov 22, 95 08:53:21 am
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Bob Bishop stands accused of saying: > > If it pops up on all 8 LUNs, either (a) it's fundamentally busted, or (b) > it's set up to the same LUN as the host adapter (probably LUN7). This can > happen by accident eg if it's in an external box with an external LUN > switch which has been miswired (connector the wrong way round). You too are confusing LUNs with IDs (aka TARGET numbers). This is common 8) On a given SCSI bus, you have 8 TARGET IDs. For each TARGET ID, there are eight LUNs. A properly compliant device should only show up on one TARGET ID, but may (depending on what it is) respond to more than one LUN. (eg. a multi-disk CD player may offer each disk on a seperate LUN. SCSI bus expanders use this technique and remangle passing headers to remap IDs and LUNs to put more than 8 devices onto a single bus. etc...) However, a device that responds identically to all eight LUNs on a given TARGET ID is most likely simply not checking the LUN field in the command header, and is thus fundamentally busted, to use your words 8) If the target code programmer was so slack as to not check the LUN field, you can be pretty sure that they've cut corners elsewhere. Whether these other corners bite you or not of course remains to be seen. > Bob Bishop (01734) 774017 international code +44 1734 -- ]] Mike Smith, Software Engineer msmith@atrad.adelaide.edu.au [[ ]] Genesis Software genesis@atrad.adelaide.edu.au [[ ]] High-speed data acquisition and (GSM mobile) 041-122-496 [[ ]] realtime instrument control (ph/fax) +61-8-267-3039 [[ ]] "Who does BSD?" "We do Chucky, we do." [[
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