Path: utzoo!censor!geac!torsqnt!lethe!yunexus!ists!helios.physics.utoronto.ca!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!samsung!emory!hubcap!ncrcae!ncr-sd!serene!cbmami!jason From: jason@cbmami.UUCP (Jason Goldberg) Newsgroups: comp.sys.amiga.hardware Subject: Re: More info on A2091 woes Message-ID: <18924eb1.ARN0df1@cbmami.UUCP> Date: 24 Jan 91 06:33:05 GMT References: <9696@cica.cica.indiana.edu> <1991Jan14.193336.13387@convex.com> <1991Jan15.155835.5230@javelin.es.com> <14480@june.cs.washington.edu> <2627@excelan.COM> <17905@cbmvax.commodore.com Reply-To: jason@cbmami.UUCP Followup-To: comp.sys.amiga.hardware Lines: 49 In article <17905@cbmvax.commodore.com>, Dave Haynie writes: > Let's try this one again: > > STEP 1: > Boyer builds the A2091, plugs in the WD33C93, and Steve proceeds to > write the device driver. In the process of this, he discovers that > there are some problems in the high level state logic of the WD33C93, > but manages to get things working by resorting to some lower level > functions. > > STEP 2: > WD discontinues the WD33C93, replacing it with the WD33C93A. This part > claims to fix the high level logic, but manages to break the low level > logic that Steve used in the A2091 device driver. So reselection > breaks. > > STEP 3: > Steve revises the device driver (in the ROM, folks), to use the > original functions that are finally corrected, and things work once > again. > This certainly clears things up for me! I will pass the info along, one question though, is it possible for someone to provide the version numbers for the two ROMs which should be used with the WD33C93 and WD33C93A respectively? Also am I correct in assuming that as long as you have one of the correct combinations of WC Chips and ROMS that you can safely use reselection? And that if you don't have the correct combination you should turn off reselection, as an interum (partial) solution until you can get it fixed? On a related (much less important issue), is it true that the ROM which works with the WD33C93A does not change memory location zero, and the one which works with the WD33C93 does change this value? I'm assuming that if you have the older combination that the only work around (for the improperly written software) is to manual set location 0 to 0. Finnaly, if a customer has the old ROM and the old WD chip (so that he is able to have reselection on) is their any reason why he might want to upgrade to the new ROM and new WD chip? Thanks for clearing this up (at least for me) ;- -Jason- --------------------------------------------------------------------------- Jason Goldberg UUCP: ucsd!serene!cbmami!jason Del Mar, CA