Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!lll-winken!uunet!cbmvax!daveh From: daveh@cbmvax.commodore.com (Dave Haynie) Newsgroups: comp.sys.amiga.hardware Subject: Re: More info on A2091 woes Message-ID: <17905@cbmvax.commodore.com> Date: 22 Jan 91 17:58:26 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> Reply-To: daveh@cbmvax.commodore.com (Dave Haynie) Organization: Commodore, West Chester, PA Lines: 50 In article greg@travis.cica.indiana.edu (Gregory TRAVIS) writes: >clay@na.excelan.com (Clay Jones) writes: >>You need a WD SCSI controller with the same part # but without the "A" on the >>end. I have been using mine A2091 with multiple drives and reselection turned >>on for about 9 months with no problems. >Do we need to order this ourselves or will Commodore buy it for us? Why >do I keep hearing rumors that Commodore is working on a ROM upgrade >to the controller, instead of replacing the WD chip? 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. >If I ordered this part from WD, could I just plug it in in place of my current >WD "PROTO" (yes, it says "Prototype" right on the chip) chip? The older part is not available anymore, WD has discontinued it. If you could manage to get hold of one, you could plug in right in place of your WD33C93A, and it would work, you could once again have reselection. A ROM upgrade will achieve the same end, only with the modern version of the SCSI chip. >Why is a ROM upgrade starting to smell like an unadulterated KLUDGE? Because you are confused. Hopefully, this has clarified things. >Gregory R. Travis Indiana University, Bloomington IN 47405 -- Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy "What works for me might work for you" -Jimmy Buffett