Date   : Sun, 13 Dec 1987104:14:00-MST
From   : Ken Wallewein <kenw%noah.arc.cdn%ubc.csnet@RELAY.CS.NET>
Subject: An Idea: An Omnibus Reference Work for CP/M

>all SSSD). Now to confuse the issue, it does not translate double-density
>sectors in the BIOS, it pre-formats them skewed!! (It will work if the

  I've been working on a format program to do exactly that for my own
8" DSDD system (S100, SD Systems controller with WD 1791, Jade Z80
CPU) so I could change skew factors without messing around in the BIOS
or figuring out some scheme to tell it what skew to use.

  I do skew calculation 'on the fly' now, rather than having to
re-build the tables, and a little experimentation has convinced me to
adopt a skew of 2 for most situations. The person from whom I bought
the system had used no skew at all. It loaded programs very quickly,
but re-logging the directories after rebooting was almost painful :-).
Unfortunately, I have a LOT of disks already recorded in that format,
and would really rather not have to go back and copy the lot over...
although, come to think of it, it might be simpler...

  I can see no reason why a PROPERLY SELECTED skew would not work very
nicely in a pre-formatted configuration. Do you know whether there
might be some reason _other_ than the choice of skew factor, which
could be causing the problem?

  If you have the source for the format program and wouldn't mind
sending me a copy, I would very much appreciate it.

/kenw