AWCTTYPA@UIAMVS.BITNET ("David A. Lyons") (03/13/89)
>Date: Fri, 10 Mar 89 20:21:28 GMT >From: "Philip R. Lindberg" > <ssc-vax!shuksan!tahoma!prl3546@BEAVER.CS.WASHINGTON.EDU> > >> The Unidisk 3.5 will NOT work on a GS.... >> >> Todd Davis > >The Unidisk will work with a GS _IF_ you use a Central Point Disk >Controller. (I have one as my second 3.5 drive) But it is slow, and GSOS >& ProDOS will not use any kind of interleaving with it. ARGGGHHH! As correctly stated in all the reference material, _both_ the Apple 3.5 and the Unidisk 3.5 work just fine off the GS's SmartPort connector. Yes, the Unidisk 3.5 is slower. "Interleave" refers to the ordering of blocks around a track. Every disk has some sort of interleave, unless you can figure out a way not to put the blocks on the tracks in some order or other. Unless the software you use to format a 3.5" disk on an Apple 3.5 or Unidisk 3.5 specifies otherwise, a 4:1 interleave is used. The loaded driver for the Apple 3.5 under GS/OS presents you with a choice of interleaves when you format. I don't remember for sure, but I bet the Unidisk driver doesn't. Under ProDOS, programs that do SmartPort calls can format with any interleave from 1:1 to 13:1. 2:1 and 4:1 are the only ones normally used. 2:1 can be read much faster under GS/OS and sometimes under ProDOS, on an _Apple 3.5_. 2:1 on a UniDisk 3.5 is slow. --David A. Lyons bitnet: awcttypa@uiamvs DAL Systems CompuServe: 72177,3233 P.O. Box 287 GEnie mail: D.LYONS2 North Liberty, IA 52317 AppleLinkPE: Dave Lyons