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12.67 Write FPDMA Queued (61h)
The Write FPDMA Queued command transfers one or more sectors of data from the host to the device, and then the
data is written to the disk media.
If an unrecoverable error occurs, the write will be terminated at the failing sector
Table 256 Write FPDMA Queued Command (61h)
Command Input
Field
Description
FEATURE
The number of logical sectors to be transferred. A value of 0000h
indicates that 65536 logical sectors are to be transferred
COUNT
Bit Description
15:14 PRIO field
13:8 Reserved
7:3 NCQ TAG field
2:0 Reserved
LBA
LBA of first logical sector to be transferred
ICC
7:0 ICC field
DEVICE
Bit Description
7
FUA bit
6
Shall be set to one
5
Reserved
4
Shall be cleared to zero
3:0 Reserved
Command
7:0 61h
FUA bit
When the FUA bit is set to 1, the completion status is indicated after the transferred data are written to the media also
when Write Cache is enabled.
When the FUA bit is set to 0, the completion status may be indicated before the transferred data are written to the
media successfully when Write Cache is enabled.
ICC field
The Isochronous Command Completion (ICC) field is valid when PRIO is set to a value of 01b. It is assigned by the
host based on the intended deadline associated with the command issued. When a deadline has expired, the device
continues to complete the command as soon as possible. The host can modify this behavior if the device supports
the NCQ Non-Data command (see Section 12.15) and supports the Deadline Handling subcommand (see Section
12.15.2). This subcommand allows the host to set whether the device aborts commands that have exceeded the time
set in ICC.
There are several parameters encoded in the ICC field: Fine or Coarse timing, Interval, and the Max Time. The
Interval indicates the time units of the Time Limit parameter.
If ICC Bit 7 cleared to zero, then the time interval is fine-grained.
Interval = 10msec
Time Limit = (ICC[6:0] + 1) * 10 msec
If ICC Bit 7 is set to one (coarse encoding), then the time interval is coarse grained.
Interval = 0.5 sec
Time Limit = (ICC[6:0] + 1) * 0.5 sec
334
Hard Disk Drive Specification