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-
- DoubleDisk (tm) Version 2.14b Release Notes
-
- Copyright (c) 1989,1990 by Vertisoft Systems, Inc.
- Copyright (c) 1989,1990 by MITAN Software Int'l (1989) Ltd.
-
- Vertisoft Systems, Inc.
- 150 Highway 9
- Freehold, NJ 07728
-
-
- ===================================================================
-
-
- Release Notes
- =============
-
- 1. The manual reflects program versions 2.12, 2.13, and 2.14.
-
- 2. This new release features several advantages over previous
- releases:
-
- * Much faster operation
- * New File UNerase support scheme
- * New "Full Shrink" option for maximum shrinking
- of Extended Disks
- * Comprehensive Verify and Recover Options
- * Complete DOS 4.x support
-
-
- DoubleDisk Installation Notes
- =============================
-
- 3. Before installing DoubleDisk, it is highly recommended that
- you perform "Gap Compression" on the Host Drive. By "Gap
- Compression" we mean reorganization of the files on your hard
- disk so they will not be too cluttered.
-
- As stated in the User's Guide, it is not advisable to use "Gap
- Compression" utilities with Extended Disk's, as they have no
- effect at all on the Extended Disk's performance due to
- DoubleDisk's propriety FAT scheme handling.
-
- Even though such utilities usually WORK with DoubleDisk, they
- might cause Actual Size inflation of small files, causing
- degradation of the overall compression ratio. The Actual Size
- those files occupy on the Extended Disk might sometimes be
- BIGGER than their DOS size.
-
- This problem will be fixed in the next release.
-
- Refer to Appendix D in the DoubleDisk User's Guide for more
- information.
-
- When installing DoubleDisk, the installation procedure saves
- the original AUTOEXEC.BAT & CONFIG.SYS into AUTOEXEC.DBL &
- CONFIG.DBL respectively.
-
-
-
-
-
-
-
-
-
-
- Virtual Capacity
- ================
-
- 4. * With DOS version 4.x, Compaq Dos 3.31, or Zenith Dos 3.3
- Plus, the default Virtual Capacity is 128MB. Due to the
- better disk management methods available with these
- versions of DOS, there is no need to select lower Virtual
- Capacities. A Virtual Capacity of 256MB is advised for
- Extended Disks larger than 100MB. Selecting a Virtual
- Capacity of 256MB will cause no performance degradation.
-
- * With other DOS versions, higher Virtual Capacity
- selection may cause slight speed and compression ratio
- degradations, as well as larger RAM memory consumption.
- Therefore, select the Virtual Capacity with care. As a
- rule of thumb, with these DOS versions, the SMALLER the
- Virtual Capacity selected - the better.
-
- * With ALL DOS versions, when creating NEW Extended Disks,
- it is best to choose the default value for the Virtual
- Capacity as suggested by DDUTIL. Specifying a smaller
- Virtual Capacity will provide no additional benefit.
- Larger Virtual Capacity is to be selected only in
- accordance with the largest amount of data expected to be
- stored on the Extended Disk.
-
-
- Supported Extended-Disks Size and Virtual Capacity
- ==================================================
-
- 5. The supported Extended Disk size depends on the DOS version in
- use:
-
- * DOS version 2.x: Each Extended Disk drive can occupy
- up to 16 MB on the Host Drive (with Virtual Capacity
- of up to 32 MB).
-
- * DOS version 3.x: Each Extended Disk drive can occupy
- up to 64 MB on the Host Drive (with Virtual Capacity
- of up to 128 MB).
-
- * DOS version 4.x, Zenith DOS 3.3 Plus & Compaq DOS
- 3.31: Each Extended Disk drive can occupy up to 128
- MB on the Host Drive (with Virtual Capacity of up to
- 256 MB).
-
- IMPORTANT! This version does not support Host Drives with
- sector size greater than 2K (used with Host Drives
- larger than 128MB with DOS versions OTHER than DOS
- 4.x, Zenith DOS 3.3 Plus, and Compaq DOS 3.31).
-
-
- Extended Disk Integrity Checking
- ================================
-
- 6. You should frequently use the DDUTIL Verify function in order
- to assure the integrity of your Extended Disks. The Verify
- fuction can be used only with Inactive Extended Disks. (Refer
- to the User's Guide for more information).
-
-
-
-
-
-
-
- If Verify finds any inconsistency problems, it displays a
- proper message, e.g.: Lost Cluster or Lost Chains found. (this
- might happen with regular DOS drives as well).
-
- If such a message appears, Verify will offer to correct the
- inconsistency problem, and will display the following prompt:
-
- Correct FAT <Y/N> ?
-
- Correcting the FAT might cause loss of data (just as with DOS
- drives). We suggest that you first backup the files on the
- Extended Disk before correcting the FAT. Answer "N" to the
- prompt, Activate the Extended Disk (using the DDUTIL Assign
- function), backup the files, and apply the Verify function
- again, this time typing "Y" to the prompt.
-
-
- DDIR reports that Actual Size is BIGGER than DOS size
- =====================================================
-
- 7. This problem may occur if either a "Gap Compression" utility
- was used with the Extended Disk (see above), or if the file
- has a very small compression ratio potential.
-
- This is due to the fact that the files are stored as is, but
- DoubleDisk uses some overhead tables which might cause this
- inflation.
-
-
- Incompatibility with certain software utilities
- ===============================================
-
- 8. Norton Disk Doctor (NDD)
-
- DoubleDisk is currently not compatible with NDD due to the
- fact that NDD treats the Extended Disk as a physical drive
- rather than sa a logocal drive.
-
- This problem is being worked out with Norton Computing Inc.,
- and it will be fixed in future releases.
-
- 9. Gazelle Systems' Quick DOS II (QD2)
-
- A problem was reported when using QD2 with directories con-
- taining more than 256 files.
-
- This problem is now being worked out.
-
-
- General Notes
- =============
-
- 10. This version of Double Disk is NOT compatible with earlier
- versions of Double Disk. Extended Disks created by earlier
- versions than this should be re-formatted using the DDUTIL
- utility version 2.14.
-
- 11. This version of Double Disk is NOT compatible with Local Area
- Networks (LANs).
-
- 12. If you are using PCTOOLS or PCTOOLS DELUXE Versions 5 & 6, Please
- note the following:
-
- YOU MUST GIVE THE DOUBLEDisk EXTENDED DISK A VOLUME LABEL.
-
- If you do not assign the DOUBLEDisk extended disk a volume
- label, your system will HANG/FREEZE when you attempt to
- change drives to the DOUBLEDisk extended disk. With out
- the VOLUME LABEL, PCTOOLS is unable to find the DOUBLEDisk
- drive. If this happens, you will not loose any data. Simply
- REBOOT your system and assign a volume label to the DOUBLEdisk
- extended disk. PCTOOLS will then operate properly.
-
-
- BACKUP/RESTORE Considerations with DoubleDisk
- =============================================
-
- If you Backup your Host-Drives (those containing the Extended-Disks) you
- probably almost always Backup the Extended-Disks as DOS files as well.
-
- Later, if you Restore some or all of the files into the Host-Drive,
- you might unintentionally Restore the OLD Extended-Disk DOS file onto
- itself, thus overwriting the current one with older data.
-
- To prevent this situation, you must specifically EXCLUDE the Extended-Disks
- DOS files (those named DUBLDISK.00x where x=0..9) from the Backup/Restore
- operation, unless you wish to use SuperFast Backup/Restore feature provided
- by DoubleDisk (refer to the section "Backing Up the Extended-Disk" in
- Chapter 3 of the User's Manual for more information).
-
- NOTE: Some Backup/Restore programs (such as DOS's own BACKUP and RESTORE
- commands) do not provide an EXCLUDE feature. In this case you should
- selectively BACKUP/RESTORE files from/into your host drive.
- In other words, do NOT use *.* as a file specification parameter for
- such BACKUP/RESTORE programs.