Re: Any utility to convert TrackStar board emulator Disk images to Emulator image files??

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

"Lazarus I. Long" <me@lazilong.com> wrote in message
68a2ec1b.0404291538.ace5c61@posting.google.com">news:68a2ec1b.0404291538.ace5c61@posting.google.com...
> someone give me the specs/format of the trackstar disk images and i'll
> write one.  :)

Hi Laz,

I have never been able to find any official specs/format information on
trackstar disk images.  As I mentioned I tried reverse engineering images I
found on the net.
After digging around I found some old notes that I made a while back.
Here is what I wrote:

--------------------------------------
What I know (or think I know):

Trackstar disk images have the ".app" MS-DOS file name extension.

They can be either ProDOS or DOS 3.3.

Everyone I have seen is 266,240 bytes long.
This is enough room for 40 tracks, each 6656 bytes long. Usually only the
standard 35 tracks are formatted.

Each track has a 128 byte header that is not encoded.  This header usually
contains some ASCII text, but is mostly filled with zeros.

The rest of the track is encoded.  The encoding used seems to be the normal
4-4 nibble encoding for the address fields and 6-2 encoding for the data
fields except that everything is written in descending order.  That is,
when reading data the last nibble of the trackstore track is the first one
read.
The tracks themselves are placed in ascending order from the beginning of
the image.
The physical sectors are in a descending order that "wrap around" as if
they were on a real disk where the start of the track could be anywhere.
When read the sectors must be skewed (interleaved) of course.  I believe
Pascal skewing is used!
Trackstar images use the normal prologue and epilogue bytes but some disk
images allow one data field epilogue to be overwritten by the 128 header
mentioned above.

Inexplicably, on some images there is an occasional address field that is
written in ascending order although these seem to serve no purpose and are
not always associated with a data field.

In a normal 35 track disk there should be 560 address fields and 560 data
fields. Unfortunately, every Trackstar image that I have found contains
less than 560 address fields and even fewer data fields.
Note this is using a routine that counts an address or data field only if
it has the proper 3 prologue bytes and the first two epilogue bytes.

Here is a list of the images I have (the numbers indicate the address &
data fields that my routine detects):

Name         Address Data OS

BLEEP.APP    0       0    ?
COPYII.APP   559     532  ProDOS
dosutils.app 558     530  DOS
filetrn.app  544     512  ProDOS
pdutiles.app 558     530  ProDOS
SAMPLRAW.APP 555     525  ProDOS
startup1.app 0       0    ?
STARTUP2.APP 162     9    ?
-------------------------------------------------------------

Obviously, I was doing something wrong, but I never figured out what.
Someday maybe I'll go back and try again.  So many formats, so little time.

Charlie