North Star DIMENSION Service Manual page 90

TROUBLESHOOTING
Fixed Disk Problems (cont.)
Symptom Explanation Solution
The fixed Although the Run CHKDSK and read the DOS Manual for an
disk has too fixed disk explanation of this utility . 24 tracks ( 208896 bytes)
many bad drive may are reserved as a bad track buffer zone. Up to
spots .
appear to 200,000 bad bytes ( over the whole disk ) are normal and
have too do not result in the loss of disk space. As SETUP and
many bad MAINT detect bad tracks, they move the ends of the
tracks, the partitions out to make up for the lost space. After
number may the 24 reserved track limitation has been exceeded,
actually be space is lost . However, the software can handle up to
within the 90, and this is still acceptable.
specification
tolerance. Read and compare the entries on the disk drive bad
track label with the following table . The maximum
allowed number of bad tracks follows:
Drive Production Limit Field Service Limit User Limit
Type of Bad Tracks of Bad Tracks
of Bad Tracks
HD 15 16
24 90
HD30 24
48 90
Examples: An HD15 off the assembly line should have
no more than 16 bad tracks; an HD15 returned from
service should have no more than 24 bad tracks. If
bad tracks increase during machine use, the software
can accommodate up to 90.
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