Echo Buffer; Mam Page Identification; Table 153 Echo Buffer Descriptor - Field Descriptions - Quantum LTO 2 User Manual

Table 153 Echo Buffer
Descriptor — Field Descriptions

Echo Buffer

MAM Page Identification

LTO-2 SCSI Interface Guide
Field Bytes
EBOS 0
Reserved 0
Reserved 1
Reserved 2
Buffer 2-3
Capacity
The
2
READ BUFFER
the most recent
WRITE BUFFER
nexus. If no
WRITE BUFFER
, then the command will terminate with CHECK CONDITION
BUFFER
status, with the sense key set to ILLEGAL REQUEST, and additional
sense code set to COMMAND SEQUENCE ERROR. IF the data in the
echo buffer has been overwritten by another IT nexus, then the
command shall be terminated with CHECK CONDITION status,
BUFFER
with the sense key set to ABORTED COMMAND, and the additional
sense code set to ECHO BUFFER OVERWRITTEN.
This section details the pages available in the MAM. Refer to the Ultrium
2
Generation I or Ultrium Generation II for the latest 8-Channel Format
Specification Documents for the latest up-to-date MAM data.
The table below shows the Page ID used to identify each page within the
MAM. Note that a Page ID of 0xFFFFFF is used when reading the entire
MAM.
An optional page will not exist unless the drive has preformed an
operation that requires information be stored to that optional page. A
command to an optional page that has not been created
READ BUFFER
will result in a check condition LUN NOT READY AUXILIARY
MEMORY NOT ACCESSIBLE.
Bits Description
0 Always 0, indicating that the echo
buffer may be overwritten by any
intervening command received on any
IT nexus.
1-7 All bits are 0.
All bits are 0.
4-7 All bits are 0.
The capacity of the drive's data buffer.
command for the echo buffer shall return data from
command for echo buffer on the same IT
command for echo buffer preceded the
Chapter 2 SCSI Commands
READ BUFFFER Command
READ
READ
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