Hitachi 7K400 - Deskstar Hard Drive Specifications page 259

SE (Status, bit 5)
DWE (Status, bit 4)
SE (Stream Error) shall be set to one if an error has occurred during the execution
of the command and the WC bit is set to one, In this case the LBA returned in
the Sector Number registers shall be the address of the first sector in error, and
the Sector Count registers shall contain the number of consecutive sectors that
may contain errors. If the WC bit is set to one when the command is issued and
an ICRC, UNC, IDNF, ABRT, or CCTO error occurs, the SE bit shall be set to one,
the ERR bit shall be cleared to zero, and the bits that would normally be set in the
Error register shall be set in the error log.
DWE (Deferred Write Error) shall be set to one if an error was detected in a
deferred write to the media. This error is from a previously issued command. If
DWE is set to one, the location of the deferred error is only reported in the Write
Stream error log.
Deskstar 7K400 Hard Disk Drive Specification
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