AT&T PC 6300 - Page 279

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DIAGNOSTICS
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2 - SEQUENTIAL READ: This test reads all the tracks on the
diskette, sector by sector. The tracks are read incrementally with
an interleaving factor of 3.
3 - FUNNEL READ AND DATA COMPARE: This test
reads all the tracks sector-by-sector, and compares each track with
the WRITE SEQUENTIAL sample pattern.
4 - VERIFY DISKETTE: This .test is the same as the
sequential read test except it does not transfer data to the memory
and no data comparisons take place.
5 - RANDOM READ: In this test, sector 1, head 0 of a random
track, is read and the data checked. This is repeated for
200 tracks.
7 - WRITE PROTECT: This test operates the write-protect
mechanism on the disk drive. In this test, sector 1, head 0 on
track 39, will be read into the buffer first. An attempt is made to
write over the same sector. Any error excep^t a write-protect error
is counted as a soft error and will be retried for the specified
number of times. It is considered a write-protect error (hard
error) if no error is found. If there is a write-protect error, the
sector is read for a second time and the data is checked for any
possible change. Any change is considered a hard error.
8 - HEAD ALIGNMENT: The purpose of the head alignment
test is to position the heads over prerecorded alignment tracks on
an alignment diskette. To allow operator flexibility, the program
will ask for the desired track number, then verify the track.
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