
  How to partition your drive
  

If your drive has not been previously partitioned for Risc-OS by your
supplier, you will have to run the !IDETool application to initialise your
drive for use.

Run the !IDETool application and it will open the main !IDETool window, listing
all IDE devices known to the IDEFS system.  The application can be safely quit
at any time by clicking on the <CLOSE> button.

When an IDE device is being accessed by !IDETool, any displayed drive icons
specific to that device are unmounted and removed from the iconbar. This
prevents file access to partitions which may be about to change.  When !IDETool
finishes the drive icons re-appear. It is recommended that any work be saved
before !IDEtool is run.

If the <ALT> key is held while !IDETool is run, it will enter search mode and
actively look for lost partitions beyond the recorded end of the disc.  This
can be used to find subsequent partitions if an earlier one has become corrupt.


1) Device selection: Select an IDE device

   To specify a particular IDE device to work with, move the pointer over the
   chosen drive entry in the device list and press <SELECT>.  Once a selection
   has been made, the Next> button will be un-greyed, allowing you to progress
   to the next screen.  When un-greyed, the <Prev icon will go back one screen.
   

2) Device Shape: Automatic/manual drive shape setting

   The Next> screen displays the physical Shape of the selected device.
   Normally the automatic setting should be used (set by default) but
   experienced users who need to specify a different shape from that
   automatically detected can manually enter the sector/head/cylinder values.
   These values are used by the formatter to format and partition the disc so,
   if changed, it is vitally important that the correct values be entered or
   disc errors will occur in use.  The automatic sectors/heads value is found
   empirically while the number of cylinders is computed from information
   returned by the drive. The only value that may require manual adjustment is
   the cylinder number if the drive reports an incorrect capacity.


3) Partition list: List and select partitions

   The Partitions list displays a list of all partitions found on a device.
   Each entry lists the partition number, name and status. The status is
   either clear - no change, has an asterisk * - flags updated, or has
   Changed.  If Changed is displayed then any previous information or
   files will be lost from the Changed partitions when the changes are
   committed to disc.  The procedure can be aborted at any time by clicking on
   the <CLOSE> button.

   If there is any unused space on the device then the <CREATE> button is
   enabled.  Clicking on this button opens a blank partition details screen.
   Up to 32 partitions can be created on one device.

   Any listed partition can be highlighted by selecting them with the mouse.
   When highlighted, the <Edit> and (Delete> buttons are un-greyed so that the
   selected partition can be deleted or have its details amended.
   Deleting a partition will lose all files stored within it.  Because
   partitions must be contiguous, all partitions after the deleted one are
   moved down the disc to fill the gap.  As a result the data stored within
   these partitions is also deleted.  The last partition on a disc can be
   deleted without affecting any of the others. This is useful in making space
   for UNIX type installations.

   BSD UNIX installation
   

   To make installation easier, the non-RiscOS partition descriptor of the
   first partition is set if there is any free space at the end of the disc.
   The type byte is set to &42 and the offset bytes are set to the first free
   cylinder.  The partition pointer is updated when partitions are changed
   and completely removed when there is no free space.  Non-RiscOS 'Raw'
   partitions can be assigned a drive number using the *Attach command so they
   can be accessed by UnixFS using Filecore DiscOps.


4) Partition details: Create/Edit partition information

   The details screen allows new partition to be created or an existing one to
   be edited.  Partitions can be added until there is insufficient free space
   on the device. Click on <OK> when finished to add the partition to the list.
   Alterations can be aborted at any time by clicking on <Cancel>.

   **The following fields will cause a partition to be CHANGED**

   <Name>: This field accepts a string which is used as the disc name.
   The unique name must be at least two characters long but no more than ten.

   <Size>: This field sets the size of the partition in megabytes.  Partitions
   can be from 1Mb to 4Gb in size (disc capacity allowing).  The size can be
   keyed in directly or adjusted using the up/down arrows.  Machines with old
   filecore can address only <512Mb partitions.  If any of these settings are
   unsuitable then a warning is given when <OK> is clicked. The space remaining
   on the drive is displayed below. 

   <Allocation unit>: This displays the proposed LFAU unit for a given size of
   partition.  This can be used to judge the optimal partition size to give
   the most efficient file storage. If unset, a default value is used suitable
   for the partition size. <Default> updates the setting with the default value.

   <RISC OS 4 format>: This enables formatting for RISC OS 4 format (F+). You
   have to have RISC OS 4 in order to do this! If you choose RISC OS 4 format,
   then you can choose lower values for the Allocation Unit. A value of 4096 is
   suggested.

   <Boot>: Sets the partitions Boot options.  This should be set to 2 - RUN
   if the partition is to be used to boot the machine.  (This can be changed
   later by IDETool or by using the *OPT command at the command line)

   <Update this partition...>:This will force a partition to be changed.  When
   updated, the partition will be initialised, and a new directory structure
   and map will be written to disc.  No other partitions will be affected.

   **IMPORTANT**
   Changing a partitions size, Boot option, allocation unit or name will delete
   any data contained within it.  This should only be done to empty partitions
   or where the loss of the partition's files is not important.

   **The following flags can be updated without CHANGING the partition**

   <Dont automount>: By default, the first eight scanned partitions will have
   a drive icon assigned to it on the iconbar. If an automatic dive icon is not
   wanted this button should be ticked. This will hide the partition from the
   desktop.  A drive icon can be assigned to a partition at any time during a
   session from the IDEFS filer menu.  This can be made permanent by re-running
   IDETool and changing this flag.  This is most useful when access is required
   to partitions when there are no more available drive icons.  Partitions can
   be temporarily unmounted so that their icon can be re-assigned to another.

   <Password protection>: When set, the read/write/availability state of the
   partition can be set.  The case sensitive password is entered in the

   <Password> field and repeated in the <confirm> field. Passwords can be from
   one to eight characters in length. The password and confirmation must be
   identical to be valid.

   The before and after password state of the partition can be set.  In a
   school environment it may be helpful if Applications partition is normally
   read only but allows full read/write access for administration once the
   password is supplied.  This will stop unauthorised deletion of files.
   Password protection of a partition can be removed by unsetting the password
   enable flag.  See also section (6) for additional password information.


5) Set Device options: Long cable mode/troubleshooting

   !IDETool intelligently works out the appropriate settings for a particular
   device based on the capability information returned by it.  This can
   sometimes be incorrect so the device options can be manually set if
   problems occur.  If things work then dont alter them!

   Some older drives do not support the standard features of the ATA-2
   specification for IDE drives. In such cases, these difficult devices can
   be made to work reliably by altering the Dont do flags.

   Long cable mode: Should be selected if an external cable is fitted to the
   interface.  This reduces the data transfer rate by 25%, allowing a better
   safety margin for the signals when using long cables to attach devices.
   The external cable should be not more than 1m in length.
   Some old IDE drives (and SYQUEST removable drives) have to run in the slower
   long cable mode as they cant cope with faster transfer rates.

   Troubleshooting:

   <Multi-sector> - some devices have defective cacheing firmware which can
   corrupt long files.  If you have difficulty loading long (>128K) files then
   try setting this flag.

   <LBA mode> - Some old devices claim to be able to use LBA block addressing to
   access the disc.  If the drive continuously returns errors then the old CHS
   mode can be forced by setting this flag. 

   <IORDY> - This should only be set if the device continually locks the
   computer as soon as it is accessed due to incorrect assertion of the IORDY
   signal.  If this flag is set then Long cable mode should also be set.


6) Low-level format: Format device / zero whole device or partition

   If your old drive has a large number of defects then they may be cured by
   low-level formatting the device. Low-level formatting completely erases all
   information on a device and writes fresh sector information to the disc.
   Some modern drives however prevent low-level formatting and implement their
   own defect management schemes (Quantum and Maxtor do this).  If it is not
   possible to format a drive, it will be erased by writing zeros to all parts
   of the disc.  There is an option to erase any CHANGED partition only.
   This is useful to invoke a drives self defect management mechanism or just
   to completely erase sensitive data from a partition.

   Because any of these operations are detrimental to data stored on the device
   they should be used with caution!  Be prepared to wait a long time while
   formatting or zeroing a disc as it may take 20mins or more.  
   
   The settings are <Dont erase or format>, <Erase changed partitions>,
   <Erase whole disc> and <Format whole disc>.
   By default a drive is not erased and not formatted.

   Any defects found after formatting or erasing will be automatically mapped
   out when the partition information is written to the disc.


7) Partition device: Commit changes and write to device

   When you are happy with your choices, they can be committed to the device
   by first typing yes in the <Yes?> field and then clicking on <Finish>.
   A status message will appear when the changes have been written to disk.
   If you have made changes that will permanently erase data from a partition,
   a further confirmation is required before the changes are made.
   If formatting or erasing have been selected then the status field will show
   the current phase of formatting, erasing or verifying and the the progress
   is indicated by the percentage hourglass. When formatting or erasing, the
   hourglass counts very slowly.  When 50% is reached, the count now moves much
   more quickly as the device is verified.  The formatter does not multi-task.

   Modifications can still be made to previous screens by clicking on <Prev and
   the whole process can be aborted at any time by clicking on <Close>.

Simtec Electronics                     !IDETool - IDE text manual Iss C 1999
Tel: 01772 812863                             Email:  info@simtec.demon.co.uk
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