Path: utzoo!utgpu!attcan!uunet!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.sys.amiga
Subject: Re: Request to Commodore (Fast File System)
Message-ID: <4649@cbmvax.UUCP>
Date: 2 Sep 88 23:31:21 GMT
References: <6177@gryphon.CTS.COM>
Organization: Commodore Technology, West Chester, PA
Lines: 37

in article <6177@gryphon.CTS.COM>, jdow@gryphon.CTS.COM (J. Dow) says:

> Er say what? I have page 49 of the DevConII notes for the hardware section open
> in front of me. Acto it there is the following sector organization:
> [internal trackdisk format stuff...]

> 16 bytes of OS recovery info per note 2 (left out here)
> four bytes header checksum
> four bytes of data area checksum
> 512 bytes of data

> And this all repeats for each sector. So the floppies DO TOO have a checksum
> safety in them besides the SECOND checksum embedded within oldfs.

Yup, there's a place for it.  However, so far as I know, it isn't being
used.  I wondered about that stuff, since it's mentioned, long ago when
I was writing the original DiskSalv.  The general consensus was that there's
nothing done with that stuff.  I think that's still the case (I don't think
1.3 did any new work on trackdisk.device).  

Perhaps Steve Beats could tell us the truth.  If this stuff really is being
used, it may delay DiskSalv 1.2 a bit...

> Or do these C= notes lie to me?

I'm sure those locations exist.  As far as I know, they're not generally
used by a filesystem.  They are also a pain to get to, since you're got to
do raw read to see 'em.  There are, of course, various kinds of lies.
Mistakes, lies, LIES, benchmarks, spec sheets, and monthly columns in BYTE
and InfoWorld.  Take yer pick...

> 	jdow@bix (where else?)

-- 
Dave Haynie  "The 32 Bit Guy"     Commodore-Amiga  "The Crew That Never Rests"
   {ihnp4|uunet|rutgers}!cbmvax!daveh      PLINK: D-DAVE H     BIX: hazy
		"I can't relax, 'cause I'm a Boinger!"