User's Manual

DLT4000 SCSI Interface
DLT4000/DLT4500/DLT4700 Cartridge Tape Subsystem 8-13
Synchronous Data Transfer Request (SDTR)
This extended message allows the target and initiator to agree on the values of the
parameters relevant to synchronous transfers. DLT4000 drive will not initiate the
Synchronous Data Transfer Request message, but relies on the Initiator to do so. The
SDTR message has the following format:
Byte 0 Extended Message Identifier – 01h
Byte 1 Length = 3
Byte 2 Message Code = 1 (SDTR msg)
Byte 3 Transfer Period (min=50. = 32h)
Byte 4 Transfer Req/Ack Offset (max=15)
Figure 8-2 SDTR Extended Message Format
_________________________ NOTE ____________________________
The tape drive supports initiating synchronous transfer negotiations with
the host, but this feature is disabled by default. To enable it, set the Mode
Select VU ERROM parameter EnaInitSyncNeg.
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