Set Features Command - Seagate ST500LX015 Product Manual

6.3.2

Set Features command

This command controls the implementation of various features that the drive supports. When the drive receives this
command, it sets BSY, checks the contents of the Features register, clears BSY and generates an interrupt. If the value in
the register does not represent a feature that the drive supports, the command is aborted. Power-on default has the read
look-ahead and write caching features enabled.
The acceptable values for the Features register are defined as follows:
Table 12 Set Features command values
02 Enable write cache (default).
H
03 Set transfer mode (based on value in Sector Count register).
H
Sector Count register values:
00 Set PIO mode to default (PIO mode 2).
H
01 Set PIO mode to default and disable IORDY (PIO mode 2).
H
08 PIO mode 0
H
09 PIO mode 1
H
0A PIO mode 2
H
0B PIO mode 3
H
0C PIO mode 4 (default)
H
20 Multiword DMA mode 0
H
21 Multiword DMA mode 1
H
22 Multiword DMA mode 2
H
40 Ultra DMA mode 0
H
41 Ultra DMA mode 1
H
42 Ultra DMA mode 2
H
43 Ultra DMA mode 3
H
44 Ultra DMA mode 4
H
45 Ultra DMA mode 5
H
46 Ultra DMA mode 6
H
55 Disable read look-ahead (read cache) feature.
H
82 Disable write cache
H
AA Enable read look-ahead (read cache) feature (default).
H
C1 Disable the Free Fall Protection feature (41
H
F1 Report full capacity available
H
At power-on, or after a hardware or software reset, the default values of the features are as indicated above
N
OTE
S U M SSHD P
EAGATE LTRA OBILE
above enables the Free Fall Protection feature)
H
M , R . D
RODUCT ANUAL EV
S ATA (SATA) I
ERIAL NTERFACE
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