147
Western Digital Hard Disk Drive OEM Specification
Word
Content
Description
97
xxxxH
Streaming Access Latency
– DMA and PIO
The worst-case access latency of the device for a streaming command is calculated as
follows:
Access Latency = (word 97) * (words(99:98) / 256)
If the Streaming Feature set is not supported by the device, the content of word 97 shall
be zero.
98
xxxxH
Streaming Performance Granularity
99
xxxxH
Streaming Performance Granularity
100-103
xxxxH
Total Number of User Addressable Logical Sectors for 48-bit commands
104
xxxxH
Streaming Transfer Time
– PIO
The worst-case sustainable transfer time per sector for the device is calculated as
follows:
Streaming Transfer Time = (word 104) * (words(99:98) / 65536)
If the Streaming Feature set is not supported by the device, the content of word 104
shall be zero.
105
0000H
Reserved
106
6003H
Physical sector size / logical sector size
15
Shall be cleared to zero
14
Shall be set to one.
13
0=Device does not have multiple logical sectors per physical sector
12
0=Device logical sector is 256 words
11-4
Reserved
3-0
0=2^0
logical sectors per physical sector
107
5A87H
Inter-seek delay for ISO-7779 acoustic testing in microseconds
108-111
xxxxH
World wide name
the optional value of the world wide name for the device
112-118
0000H
Reserved
119
40DCh
Supported settings (Continued from word 84:82)
15
Shall be cleared to zero
14
Shall be set to one.
13-8
Reserved
7
1=Extended Power Conditions feature set is supported
6
1=Sense data is supported
5
0=Free-fall Control feature set is not supported
4
1=The segmented feature for download microcode is supported.
3
1=The READ/ WRITE LOG DMA EXT commands are supported.
2
1=Write Uncorrectable is supported.
1
0=Write-Read-Verify feature set is not supported
0
Reserved
120
409Ch
Command set/feature enabled/supported. (Continued from word 87:85)
15
Shall be cleared to zero
14
Shall be set to one.
13-8
Reserved
7
1=Extended Power Conditions feature set is enabled
6
0=Sense data is disabled
5
0=Free-fall Control feature set is disabled
4
1=The segmented feature for download microcode is supported.
3
1=The READ/ WRITE LOG DMA EXT commands are supported.
2
1=Write Uncorrectable is supported.
1
0=Write-Read-Verify feature set is not enabled
0
Reserved
Table 120 Identify device information -Continued-
