Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!usc!brutus.cs.uiuc.edu!apple!mattd From: mattd@Apple.COM (Matt Deatherage) Newsgroups: comp.sys.apple Subject: Re: ProSel 16 SCSI warning Message-ID: <37904@apple.Apple.COM> Date: 17 Jan 90 22:47:54 GMT References: <900115194155.699954@DOCKMASTER.ARPA> Organization: Apple Computer Inc, Cupertino, CA Lines: 31 In article <900115194155.699954@DOCKMASTER.ARPA> TMPLee@DOCKMASTER.ARPA writes: >The most recent version of ProSel that I have (5/89 -- I know its not >THE most recent) came with the following warning: > [warning about SCSI and concerns deleted] This was a problem in the 4.0 SCSI Driver that was fixed by a patch by Glen. Apple didn't fix it because the 5.0 SCSI Manager was about 2 weeks away from announcement at that point. The Manager was totally redone and did not suffer from this particular bug? So wait, I can see you folks panicking now - "But if there's problems with the 4.0 SCSI Driver and the 5.0 SCSI Manager, what am I supposed to use?" If you ask me, the 5.0 SCSI problem is nothing to lose sleep over; at least not too much sleep. (Forgive that semicolon.) The bug occurs when data over 3 banks is copied - in other words, you start somewhere in bank A, continue through all of bank B and end in bank C. This could be as little data copied as 64K + 2 bytes, but will always happen with 128K + 1 byte or more of data. When this happens, the Manager messes up the last 512 bytes in the block. Only the Finder (to my knowledge) is copying data in such huge chunks that this could even be noticed as a problem. I personally have few qualms about using the 5.0 SCSI Manager and I recommend you do the same. -- ============================================================================ Matt Deatherage, Apple Computer, Inc. | "The opinions represented here are Developer Technical Support, Apple II | not necessarily those of Apple Group. Personal mail only, please. | Computer, Inc. Remember that." ============================================================================