Filter
Top Products
Video 3.5 HDD Product Manual, Rev. H 37
www.seagate.com
Serial ATA Interface
4.3.2 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:
6 Ultra DMA mode 6 is supported.
8 Ultra DMA mode 0 is currently active.
9 Ultra DMA mode 1 is currently active.
10 Ultra DMA mode 2 is currently active.
11 Ultra DMA mode 3 is currently active.
12 Ultra DMA mode 4 is currently active.
13 Ultra DMA mode 5 is currently active.
14 Ultra DMA mode 6 is currently active.
Table 10 Set Features command values
02
H
Enable write cache (default).
03
H
Set transfer mode (based on value in Sector Count register).
Sector Count register values:
00
H
Set PIO mode to default (PIO mode 2).
01
H
Set PIO mode to default and disable IORDY (PIO mode 2).
08
H
PIO mode 0
09
H
PIO mode 1
0A
H
PIO mode 2
0B
H
PIO mode 3
0C
H
PIO mode 4 (default)
20
H
Multiword DMA mode 0
21
H
Multiword DMA mode 1
22
H
Multiword DMA mode 2
40
H
Ultra DMA mode 0
41
H
Ultra DMA mode 1
42
H
Ultra DMA mode 2
43
H
Ultra DMA mode 3
44
H
Ultra DMA mode 4
45
H
Ultra DMA mode 5
46
H
Ultra DMA mode 6
06
H
Enable the PUIS feature set,
Table 9 Bit Descriptions (continued)