Fibre Channel Interface Manual, Rev. D 315

12.52 Synchronize Cache (16) command

The Synchronize Cache (16) command ensures that logical blocks in the cache memory, within the specified

range, have their most recent data value recorded on the physical medium. If a more recent data value for a

logical block within the specified range exists in the cache memory than on the physical medium, then the logi-

cal block from the cache memory is written to the physical medium. Logical blocks are not necessarily removed

from the cache memory as a result of the synchronize cache operation.

Field definitions (listed alphabetically)
Control
See Control Bytes in Section 11.2.1.6.
Immed (Immediate)
1 The drive returns status as soon as the command descriptor block has been validated.
0 The status is not returned until the operation has been completed.
1 If the target does not support it, the command terminates with Check Condition status. The sense key is set to Illegal
Request and the additional sense code is set to Invalid Field in CDB.
Logical Block Address
The logical block at which the Synchronize Cache operation begins.
Number of Blocks
The total number of contiguous logical blocks within the range. A number of blocks of zero indicates that all remaining logi-
cal blocks on the logical unit are within the range.
A logical block within the specified range that is not in cache memory is not considered an error. Multiple locks may be in
effect from more than one initiator. Locks from different initiators may overlap. An unlock of an overlapped area does not
release the lock of another initiator.
RelAdr (Relative Address)
This function is not supported by drives described in this manual.

Table 215: Synchronize Cache (16) command (91h)

Bit
Byte
76543210
010010001
100000000
Reserved Immed RelAdr
2(MSB)
: Logical Block Address
9(LSB)
10 (MSB)
Number of Blocks :
13 (LSB)
14 Reserved
15 Control
91h
Table
number
215
215
215
215
215