user manual

4.2 Data Access Commands
C141-C013 217
Even when there is an error in the specification in the CDB, or
when a write operation to the disk media cannot be executed
normally due to various other causes, the transfer of data (data is
pre-fetched to the data buffer) from the INIT to the HDD may be
executed. In this case, the length of data transferred from the INIT
to the HDD is undefined. Also, all the data transferred to the HDD
will not necessarily be actually written to the disk media. However,
if the command is terminated with a CHECK CONDITION status
and the sense key of the sense data indicates "ILLEGAL REQUEST
[=5]," the data from that command is not written to the disk media
by a write operation.