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+++General

Open any copy of AHDI.PRG or SHDRIVER.SYS and then edit the patchable
variables described below.  (Variables that aren't available for a
given driver version will be disabled).  When you are finished editing
you can save the modified driver either under its original name (Save)
or under a new name (Save As).  When saving under the original name
you can auto- matically have a backup of the original created by
selecting the 'Backup' item in the Options menu.


+++Version Number

This is the version number of the driver that was opened.  Only
versions 3.00 and above may be opened.  The version number is not
editable and is displayed only for your information


+++OS Pool Size

This is the number of blocks to add to the OS Pool.  This value is
only used when the ROM version on your system requires that OS Pool be
added. 


+++Sector Size

The driver will use the bigger of this number and the largest logical
sector it can find on all logical drives at boot time, to be the size
of the buffers that GEMDOS will use.  This is useful when you are
using a removable media drive (e.g.  MEGAFILE 44) and need to use a
cartridge fomatted with a larger sector size than the one you
initially booted with.  As long as this number is greater than the new
cartridge's sector size, you can swap media without needing to reboot
your system.  (The sector size must be a multiple of 512 bytes).


+++Idle Time

This value is the time in hours, minutes & seconds before your hard
drive will spin down to conserve power.  It is only applicable to
driver versions 3.02 (Stacy) and 5.00 and above (for IDE drives like
those in the ST Book).  The number here should be a multiple of 5
seconds.  Note: Holding the shift key while scrolling causes the idle
time to scroll by minutes instead of in 5 second increments.


+++Scan Units

For each type of physical drive (ACSI, SCSI or IDE) you can decide
whether or not to scan for physical unit numbers.  For ACSI and IDE
drives you can either select 'All' to scan units 0 to 7 or 'Custom',
which brings up a dialog letting you select unit numbers individually.
Only unit 0 is supported for IDE drives.  If you select to scan for
units for one drive type, then scanning will also be performed for the
other drive types (but only for the units specified for those drive
types).  If you choose not to scan for any of the drive types then all
connected drives of a given type must have consecutive physical unit
numbers and the driver will only look as far as the first
non-responding physical unit number.


+++Removable Media Drive Letters

These two columns let you set the number of drive letters that will be
reserved for each physical unit, if that unit is a removable hard
drive.  This is useful if you will be swapping cartridges on a
removable media drive, and the cartridges are partitioned differently.
At boot time, the driver will use this number, or the number of
logical drives on a removable unit, whichever is bigger, and assign
that number of drive letters to that particular unit.  As long as
every cartridge you put into that unit during a given session has no
more than this number of partitions, you will always be able to access
all of the partitions without re-booting your system.  Remember,
however, that you only have 14 drive letters to split between all
fixed and removable drives.
