The Disk Doctor help information: The Disk Doctor was developed to diagnose possible disk problems. The majority of all disk errors is due to it's power supply in some way. I recomend first checking your 5 volts which powers the boards connected with the drive. Second, check your 12 volts which powers the mechanical parts of the drive. If your voltages are OK then the problem could be bad AC. Make sure that your computer and subsystem devices and any other device which is connected to your computer is connected to an Uniteruptable power supply (UPS) with isolated ground. This could limit shock to any device due to bad AC power . Remember, current flows to the place of least resistance and many times the place of least resistance is your disk drive in the middle of a read or write. Another possible culprit is static , which can travel down your RS232 or RS422 cable and hit the disk. These villians account for about 80% of all disk errors. Remember your disk drive was made to last a reasonable amount of time so you never know when your disk just might not want to work for you. Please remember to do your backups. The rule of thumb is backup as often as you can afford to lose data. The DISK DOCTOR SHOULD BE RUN WITHOUT ANYONE ELSE ON THE SYSTEM. If you run it with someone on the system you risk the possibility of data loss if you run the WRITE selection only. Never is the saying "An once of prevention is worth a pound of cure" more meaningful than with computers. 1. Help The help command will display this message. This file is called DSKDOC.TXT . This file should be placed in the same PPN that DSKDOC.RUN is run from. 2. Select Drive The select drive command will allow you to change the logical you wish to test . The default drive is DSK0: . If you wish to change this press return when the Select Drive is highlighted . You will be queried with "Input Drive name Ex. DSK0: >" . You can now select any logical drive defined on your system . The drive you select will now be displayed in the lower right hand side of your CRT. Make sure you include the logical drive number and end with a colon ":". 3. Mounted Drive The mounted drive command will allow you to display the drives currently mounted on your system . These are the only drives you can use for the "Select Drive" command. 4. Read The Read command will read every block on a logical drive . While the Disk Doctor is reading you will be updated as to the block number the Disk Doctor is currently reading . This update is displayed in either hex or octal depending on which you have set . If you also have DSKERR set you will be able to locate suspect blocks on your logical drive. The read command will display the total number of blocks which will be read in Decimal and the block at which it will start , which is block 0 in all cases. 5. Write The Write command will read every block then rewrite every block on the logical you have specified . If the block cannot be read then the Disk Doctor will either zero out that block or if unable to locate that block skip it and goto the next sequential block. While the Disk Doctor is reading you will be updated as to the block number the Disk Doctor is currently writing . This update is displayed in either hex or octal depending on which you have set . If you also have DSKERR set you will be able to locate suspect blocks on your logical drive. The Write command will display the total number of blocks which will be read in Decimal and the block at which it will start , which is block 0 in all cases. 6. Statistics The Statistics command will display the statistics for your drive. These statistics are only going to be valid for the MFM ST-506 "SASI" type drives . What this command performs is FIXGAR on the disk driver in DVR: . If you do not have your disk driver in DVR: this command will not find your driver . If you specify your system Disk make sure the driver specified during mongen is also called DSK.DVR . The last information Statistics will display is the amount of total and contiguous free blocks for this logical. .