Loadstar 128 21/q21.d81/t.docs 3

Text File | 2022-08-28 | 13KB | 259 lines

* * * HEADER/FORMAT UTILITY * * *

It may seem superfluous to include a disk formatting utility since
formatting can be done using the DOS commands.  This utility however
provides a painless way to format disks in a variety of ways.  You can also
change the disk name and ID characters without losing data.  You are
presented a menu which offers the various options available for the disk
drive you are using.  This utility won't work with RAMDOS, if you need to
reformat your RAM disk, use the DOS command option.

Please note that you should insert the disk you want to use before making a
selection, as some selections require to read data from the disk to work.
The various options are as follows:

Change header name (all drives):
Change the disk name without disturbing the disk contents.  The current disk
name is displayed.  The header ID is also displayed, and the "real" ID is
displayed in parenthesis (unless you are accessing a 1581 drive which
doesn't use a "real" ID).  You may now enter a new name and/or ID
characters.  A comma separates the name from the ID.  You have three
alternatives:

Change name only:  Enter the new name and no comma.
Change ID only  :  Enter a comma, then the new ID characters.
Change name & ID:  Enter new name, a comma, then ID characters.

The computer will check if the name is legal (a disk name must be between 1
and 16 character long, and the ID must be exactly two characters).  If
something is wrong, you are prompted to re-enter the name and/or ID.

The new name and ID combination are displayed, and you are asked if it is OK
to proceed.  Check that the name and ID really are OK, and press the Y key
to write the new header onto the disk.

PLEASE NOTE about the difference between header ID and real ID:  When a disk
is formatted two identification characters (called ID) are written to each
and every disk block.  The disk drive use the ID to distinguish between the
various disks.  The ID is also placed into the disk header so that you can
check the ID characters used.  You can change the header ID using this
utility, but the actual ID as seen by the disk drive, the ID that is written
to each disk block, does not change.  It is recommended that each of your
disks is assigned its own unique ID, so having another ID on your directory
than your drive actually use will only complicate matters.  It is therefore
good practice to leave the header ID alone.  DISKSERVANT will let you change
the header ID if you want to disregard good practice or set the ID back to
the proper value.  The 1581 doesn't need the ID, so you may change the ID on
1581 disks at will.


PLEASE NOTE about the following selections:  When asked for a disk name and
ID you must enter both, and DISKSERVANT will check if the name is legal (a
disk name must be between 1 and 16 character long, and the ID must be
exactly two characters).  You're asked if it is OK to proceed.  Check that
the name and ID really are OK (and that you are about to format the right
disk!), and press the Y key to initiate the format process.

Format single sided (1541 & 1571):
Formats the front side of a disk.  On the 1571, this results in a single
sided 170K disk which is compatible with 1541 disk drives.

Format whole disk (1571 & 1581):
Formats both sides of a disk.  On the 1581, the whole disk is formatted, not
just the current selected partition.

Format back side (1571):
The 1571 can use the back side of a disk as a totally separate single sided
disk, without flipping the disk over.  The front side of the disk should be
formatted as a single sided disk (or not be formatted at all).  This has
little but novelty value, as the back side formatted this way can't be read
by a 1541 disk drive by flipping the disk over.  To create a double sided
disk readable on a 1541, format the disk single sided, flip it over, and
format the back side likewise using the "format single sided" option
discussed above.

I can imagine two reasons for using this format:  1) The data can be hidden
from prying eyes.  2) If you need to store many small files on the disk you
may reach the maximum 144 files.  Formatting the back side will let you
store another 144 files on the disk.  To access the back side in your own
programs you must use these two commands: 'u0>m0' then 'u0>h1'.  To get
back, use 'u0>m1'.  In BASIC this would look like:

To access the back side:    To get back:
10 open 1,8,15              10 open 1,8,15
20 print#1,"u0>m1"          20 print#1,"u0>m1"
30 print#1,"u0>h1"          30 close 1
40 close 1
                       Alternative format:
                       10 open 1,8,15,"u0>m1":close1

PLEASE NOTE:  When the back side of the disk has been formatted, the disk
drive is reset to its normal condition.  To access the back side, you must
select the back side manually.

Convert to double sided (1571):
Most software is supplied on single sided disks to accommodate users having
access to 1541 disk drives only.  You may want to utilize the software using
the increased storage space available on a double sided disk.  The best way
is always to file copy all the files to a separate double sided disk.  This
is not always possible however.  The disk might contain data which is not
transferable by a file copier.  In such situations this utility may come in
handy.  It will convert a single sided disk to double sided without
disturbing the data on the front side.

WARNING!  This operation should never be performed on an original disk
unless you are absolutely sure about what you do.  Use the Disk Copier to
make a backup, and try to convert the backup, NOT the original.  Make sure
that nothing important is stored on the back side of the disk.  Flip the
disk over and try to read the disk directory before attempting the
conversion.

Some problems may arise when trying to convert a disk:

1) The disk is already double sided.  You're informed about this, and the
conversion is aborted.
2) The disk is not a standard formatted 1541 disk.  DISKSERVANT will inform
you about this and you'll once again be asked if it's OK to proceed.  This
condition may be caused by a number of things.  DISKSERVANT detects this by
checking the dual sided flag (a byte in the header which tells if the disk
is single or double sided) and checking the area where the BAM for the back
side of the disk is to be stored (a part of the back side BAM is stored near
the end of the front side header block).  Both the double sided flag and the
back side BAM area should all contain zeros.  Any nonzero value is detected
by DISKSERVANT, and great caution must be taken.  Some software actually
stores data in these areas, or the BAM area might contain data which is
necessary for the software to boot.  Overwriting such information may render
the software unusable.  On the other hand, overwriting the BAM area might be
quite harmless.  For example, some hackers exchange secret messages using
this area.  There are also a number of reasons why plain garbage might be
present in the BAM area.
3) The software might not be usable, even if no vital data is overwritten.
The software may have been written exclusively for use on single sided disk
for some reason or another.  The software might refuse to load, hang up, act
strangely, or work perfectly but be unable to exploit the extra disk space.
I can not offer any further advice on this, other that you go back and use
your original disk.  Please note however, that the conversion might not be
the reason why the software won't work.  If the original disk was copy
protected, it won't be able to run from the copy disk in any case.

Fix double sided flag (1571):
This utility will flip the double sided flag on a disk.  If the flag was
cleared (rendering the disk single sided) it is set, and if it is set it is
cleared.  You're asked if it is OK to proceed.  Check that you are indeed
trying to convert the right disk.

You may want to use this utility if you have inadvertently validated a
double sided disk while the disk drive was in single sided mode.  A bug in
the old 1571 ROM will render the disk single sided, while important data
might be stored on the back side of the disk.  This condition is easily
detect