Re: Help with NIB, PO, and DO?

["Charlie" <charlied@NOSPAMbboard.com>]

"Rubywand" <rubywand@swbell.net> wrote in message
3B42D38F.3510458A@swbell.net">news:3B42D38F.3510458A@swbell.net...

>      For sure, Beneath Apple DOS is one of the best two or three Apple II
books
> ever. There is one notable glitch which caused me all sorts of problems
when I
> first looked at sector ordering and tried translating DOS 3.3 sector
naming to
> ProDOS half-blocks. On page 3-23, the "DOS 3.3 Sector" listing is
incorrect.
>
>      Evidently, the writers misinterpreted the sector interleave table
(which
> usually resides at $BFB8-$BFC7 when DOS 3.3 is loaded).  The table is
entered
> with the DOS 3.3 sector name as the index to obtain the Physical Sector;
not
> the other way around.
>
>      If you swap the header labels "Physical Sector" and "DOS 3.3 Sector"
on
> page 3-23, the listing is correct for DOS 3.3. (There's a good listing of
5.25"
> Physical sectors, DOS 3.3 sectors, and ProDOS half-blocks on page 132 of
the
> Copy II Plus Version 9 manual.)
>
>
>
> Rubywand

My copy of "Beneath Apple DOS" (5th printing March 1983) lists the physical
sectors in ascending numerical order (the way they actually are on the disk
in DOS 3.3) and then the DOS 3.3 logical sector numbers.  The numbers match
those you gave in another reply.  Possibly by the 5th printing they had
discovered the error.  I had an earlier copy but it was "borrowed" about 18
years ago and I'm beginning to think it isn't going to be returned.

Charlie