Siemens Microfloppy FDD100-5 Operating And Maintenance Manual page 46

that may be falsely attributed to disk drive failure or maladjustment. Unless visual inspection of the
disk driver discloses an obvious misalignment or broken part, attempt to repeat the fault with the
original diskette; then attempt to duplicate the fault on a second diskette.
5.3 ERROR RATES
Errors may occur in Write, Read, or Seek operations. The error rate for each of these operations is
defined in the following paragraphs.
5.3.1 WRITE ERROR RATE
For successful writing of a record, the Write operation should always be followed by a Write Check
or Read operation during the next diskette rotation. Not more than five such Write and verification
attempts is recommended. If a record cannot be successfully written within five attempts, that
sector or track must be labeled defective and an alternate sector or track must be assigned. If more
than two defective tracks are encountered, the diskette should be replaced.
5.3.2 READ ERROR RATE
If a Read error occurs, up to ten attempts should be made to recover data. Repositioning the head
on the desired track is recommended if the error persists. The Read recoverable error rate is not
greater than 1 in 10 9 bits transferred. The Read unrecoverable error rate is not greater than 1 in
10 12 bits transferred.
5.3.3 SEEK ERROR RATE
Unless the stepping rate is exceeded, seek errors will rarely occur. Recalibration of track location
can be achieved by initiating Step commands until track
~~
is sensed. The seek error rate is not
greater than 1 in 10 6 seeks.
5.4 ERROR DETECTION AND CORRECTION
Detection and correction of write and read errors is described in the following paragraphs.
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