Seagate Fibre Channel Interface - Manual (Page 356)

342 Fibre Channel Interface Manual, Rev. D
12.68 XDRead (10) command
The XDRead (10) command requests that the target transfer the xor data generated by an XDWrite or Regen-
erate command to the initiator.
If the logical unit is reserved, a reservation conflict occurs when an XDRead command is received from an ini-
tiator other than the one holding the logical unit reservation. The command is rejected with Reservation Con-
flict status if the reservation conflict is due to a logical unit reservation. The XDRead command is evaluated for
extent reservation conflicts. XDRead commands with a reservation conflict is terminated with Check Condition
status and the sense key is set to Data Protect if any part of the XDRead operation is prohibited by an extent
reservation.
The xor data transferred is identified by the logical block address and transfer length. The logical block address
and transfer length is the same as, or a subset of, those specified in a prior XDWrite or Regenerate command.
If a match is not found, the command is terminated with a Check Condition status. The sense data is set to Ille-
gal Request: Invalid Field in CDB.
Field definitions (listed alphabetically)
Byte Transfer Length
The number of bytes of data that will be transferred. A transfer length of zero (0) indicates that no bytes will be transferred.
This condition is not considered an error.
Control
See Section 11.2.1.6.
Logical Block Address
The 32-bit address of the logical block affected by this command.
Table 233: XDRead (10) command (52h)
Bit
Byte
7 6 5 4 3 2 1 0
0 0 1 0 1 0 0 1 0
1
Reserved
2
Logical Block Address (MSB)
3
Logical Block Address
4
Logical Block Address
5
Logical Block Address (LSB)
6
Reserved
7
Byte Transfer Length (MSB)
8
Byte Transfer Length (LSB)
9
Control
52h
Table
number
233
233
233