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The screen will display:
By addressing the directory and observing the display, you have now confirmed
that the computer has assigned a name to your newly formatted disk, "new disk"
and that 99 is the ID. The directory is where you will also find the name of each
disk file that is saved on the disk as well as the number of blocks available for
storage of information.
Initializing Your Disk
2040 Disk Drive
STEP 3: If you have removed the disk from drive 1 for any reason, it will have to be
initialized in order for the computer to know that there is a data storage device in
drive
1.
Initialize your disk as follows:
Type: open 1,8,15
print#l,"il "
Your disk is now both formatted and initialized. Remember that formatting is
usually a one-time operation and that re-formatting a disk will destroy the data
previously stored on the diskette. Initialization, however, is necessary each time
the disk is inserted into a drive since the computer must know this information in
order to load or save a disk file. Attempting to load or save a file onto a disk
which has not been initialized may result in an error message to the display indi-
cating "Disk ID Mismatch". The disk will then have to be initialized before it can
be used in the system.
The INITIALIZE command aligns the read/write head with track 1 on the speci-
fied diskette. It then moves to track 18, reads the disk label and ID, and loads this
information into the Disk Operating System (DOS) memory. Since the 2040
initialization function depends upon a change of ID to detect a change of diskette,
inserting a diskette with ID identical to one previously used may lead to a loss of
data. This will happen because the computer will reference an internal map of the
previous disk's available blocks for storage of data since the ID's are identical. In
fact, since the ID's are identical, the computer assumes that there was no change
of diskettes at all since it compares ID's to detect a change. A DSAVE command
would now cause new data to be written over good data already resident on the
disk because the computer will use the last disk's map of available storage area,
and not the current one. After all, the ID's do match. The resultant chaos from
over-writing data is usually sufficient to convince anyone to use separate,
distinct ID's when using the HEADER command, and always to initialize a
diskette when inserting it into a 2040.
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