Re: Transferring disk images to disks with an Apple IIe

["schmidtd" <schmidtd@my-deja.com>]

On Feb 27, 12:07 am, SlickRCBD <slickr...@nospam.com> wrote:
> Ok, I phrased it badly. A .dsk file is larger than the AVAILABLE storage
> capacity of a 5.25" disk. The overhead for the directory information and
> volumen bitmap make it impossible to fit a .dsk file on a 5.25" disk.
Ah, ok.  Now I see where you're coming from.  A .dsk file is a full-
disk, bit-for-bit image of the floppy.  It _includes_ all the
directory and volume information bits.  Whatever was on the disk
before is completely overwritten, bit for bit, with the new image.
(Discussion of quarter-tracks, .nib images, etc. left to another day.)

> Not to mention that since his IIe only has 128K of RAM, he can't store
> it in memory (128K < 143360 bytes ).
That's where this new-fangled ADT helps.  It segments a disk into
seven 20k segments and sends those one at a time to/from a 20k buffer
at the Apple side.  When writing a physical floppy, the buffer
contents are written out to the appropriate disk sectors without
regard to what was there before; when reading, sectors are pulled off
the disk and stored in the buffer for transfer back out.

> To reply to the other posts, I've never heard of this ADT program.
[...]
> When was it released?
ADT in its current incarnation started in 1995.  It's been going
through major revisions every 5 years or so. :-)  See the "ADT
Lineage" section at the bottom of this page:
http://adtpro.sourceforge.net/credits.html
The ADT program itself can be downloaded here:
http://adt.berlios.de