Spectra Logic Spectra S50 User Manual page 146

Appendix B. Extended Copy—83h—SPC2 Specifications
will be written to the destination stream device identified by the Destination Target
Descriptor Index field starting at the current position of the stream device. Any
residual destination data from a previous segment descriptor will be written before the
data of the current segment descriptor. Any residual source data from a previous
segment descriptor will not be processed, and will be handled as residual source data.
The CAT bit is described in Segment Descriptors on page 133.
The Descriptor Length field will contain the length in bytes of the fields that follow the
Descriptor Length field (including embedded data). The value in the Descriptor Length
field will be a multiple of 4.
The Destination Target Descriptor Index field is described in Segment Descriptors on
page 133.
The Stream Device Transfer Length field specifies the amount of data to be written to
the stream device on each write operation. See Device Type Specific Target Descriptor
Parameters for Stream Device Types on page 131 for a description of how data in the
Stream Device Transfer Length field in the segment descriptor interacts with data in the
Stream Block Length field in the device type specific target descriptor parameters for
the destination sequential-access device type.
The Embedded Data Number of Bytes field specifies the number of bytes of embedded
data that are to be transferred to the stream device. A value of zero will not be
considered an error. The Embedded Data Number of Bytes value will be less than or
equal to the Descriptor Length value minus 12.
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