******************************************************************************* SCSI Tape Backup Utility - Version 1.02 Copyright (c) 1989 by Larry W. Beam All Rights Reserved Released - 89/09/07 ******************************************************************************* WARNING - Improper use of this utility can result in the loss of some or all data on your hard drive or tape backup, with no chance of recovery! ******************************************************************************* SCSI Tape Backup Utility is FREEWARE. It is copyright material but can be used and distributed free of charge to anyone for personal, non-commercial use. The author makes no warranty or representation, either expressed or implied, with respect to this software, its quality, performance or fitness for any particular purpose. As a result, this software is distributed 'AS IS,' and the user assumes the entire risk as to its quality and performance. INTRODUCTION SCSI Tape Backup Utility is a simple ProDOS-8 program which can be used to backup a SCSI hard drive on a 3M DC2000 tape. This is done by making a block for block image of an entire hard drive partition on the tape. The program can also be used to restore the hard drive partition from the tape image as well as format and rewind tapes. USING THE UTILITY The utility begins by checking for an Apple II SCSI Card with a Rev C ROM. If a SCSI card is not found, an error message is displayed. The first SCSI card found is then checked to see if a tape drive and at least one hard drive are connected. The tape drive must have the lowest priority on the SCSI bus (ie, its SCSI ID must be 0). Appropriate error messages are displayed if the above conditions are not met. As soon as a tape is placed in the tape drive it is re-tensioned by winding the tape to the end and back again. The entire process takes about 30 seconds to complete and when finished, the light on the front of the tape drive should not be flashing (if this light is flashing, see below). Backup Hard Drive - This option allows you to copy the contents of one hard drive partition onto a 3M DC2000 tape. This process takes about 5 minutes per megabyte of storage space allocated to the partition and destroys all data previously saved on the tape. You will be requested to enter the unit number of the hard drive to be backed up. Acceptable unit numbers are 1 to 6, depending on the number of block storage devices connected and their partitioning. Under ProDOS-8, if the SCSI card is located in slot 5, up to four block storage devices may be connected; devices 1 and 2 appear as drives 1 and 2 in slot 5 and devices 3 and 4 are mapped into slot 2, drives 1 and 2, respectively. In addition, the program will recognize two more devices, which normally could be accessed only by GS/OS. Once the unit number has been entered, the volume name of the selected device is displayed and you will be requested to confirm your choice. Once the process has started, a 5 digit number will appear. This is the running total of the number of blocks copied (the total number to be copied may be obtained by CATALOGing the partition prior to starting). The backup process may be stopped at any time by pressing the ESCAPE key. When the backup process is finished a distinct tone will sound twice and "Process Successfully Completed" will appear on the screen. Restore Hard Drive - This option allows you to restore the contents of one hard drive partition from the tape image created by the previous option. This process takes about 5 minutes per megabyte of storage space allocated to the partition and will return the partition to the state it was in at the time the backup was made. All files and data saved since the backup will be destroyed. You will be requested to enter the unit number of the hard drive to be restored. Acceptable unit numbers are 1 to 6, depending on the number of block storage devices connected and their partitioning. Once the unit number has been entered, the volume name of the selected device is displayed and you will be requested to confirm your choice. Once the process has started, a 5 digit number will appear. This is the running total of the number of blocks copied. The restore process may be stopped at any time by pressing the ESCAPE key. When the restore process is finished a distinct tone will sound twice and "Process Successfully Completed" will appear on the screen. Format Tape - This option allows you to perform a low-level format on a tape (blank or otherwise). This process takes about 40 minutes and destroys all data previously saved on the tape, with no chance of recovery. You will be requested to enter an interleave value used during the format process. Acceptable interleave values are 0 and 2 through 7. Entering 0 will result in the default value of 2 being used. From limited tests carried out by the author, an interleave value of 2 is recommended, as it appears to result in the fastest tape access time. The tape is formatted with a block size of 8192 ($2000) bytes. When the format process is finished a distinct tone will sound twice and "Process Successfully Completed" will appear on the screen. Rewind Tape - This option allows you to rewind the tape prior to ejecting it. This is done by issuing a SCSI StopUnit command to the tape drive (see below). When the rewind process is finished a distinct tone will sound twice and "Process Successfully Completed" will appear on the screen. Quit - This option allows you to leave the program. This is done by issuing the ProDOS-8 MLI QUIT call. NEW TAPES AND OTHER PROBLEMS Formatting a New Tape - When attempting to format a new tape, the program may at first appear to do nothing. There could be two reasons for this. First, for reasons unknown to the author, the tape drive refuses to respond for about two minutes. The solution is to just be patient and the drive will eventually respond. Second, the SCSI bus may have lost track of the tape drive. This is not limited to the formatting of new tapes, as it may occur at anytime. The solution is to press CNTL-RESET (just RESET on a II+) and re-select the desired option. To determine which of these situations has occurred, press any key not used for option selection. If the response is a single 'BEEP', then the second situation has occurred. NEVER, NEVER press CNTL-RESET when the hard drive or tape drive are being accessed!!! Tape Drive Light Flashing - If the light on the front of the tape drive is flashing at the end of the re-tensioning sequence, an error has occurred and the tape drive will not operate. This could be due to several things, such as a bad tape, a defective tape drive or external magnetic or RF interference. To determine which, start by trying another tape. Next, disconnect the tape drive from the SCSI bus and try again. If this does not work, try to test the tape drive as far away from all electrical equipment as possible (especially your computer monitor). Finally, the interference may be coming from the tape drive's power supply (removing the cover from the case may help). If the problem persists, it is likely that the tape drive is defective. Hard Drive Crashes - During development of this program, the author experienced several hard drive crashes. It is his opinion that they were due to a problem with the Rewind option. Prior to the release of the original version of this program, the author believed that this problem had been fixed. It has been reported that the original version of this program may have been responsible for at least one hard drive crash. The author has attempted to correct this problem, however, if you should experience any problem which may be attributed to this program, please discontinue using it immediately and notify the author. As a precaution, you may wish to re-boot your computer after rewinding a tape. Write Protection - If the program displays the "Device Write-Protected!" error message, check the write protection gizmo on the tape. It should be positioned as close to the edge of the cartridge as possible. |