K6610170
Rev.2
Dec 22, 2004
- 97 -
7.5.35. Set Features [EFh]
Task
File
Registers
7 6 5 4 3 2 1 0
Command EFh
LBA High
XX
LBA Mid
XX
LBA Low
XX
Device/Head
X X X
DRV
X X X X
Sector Count
Refer to Table 7.25
Features
Refer to Table 7.25
This command is used to specify the parameters shown in Table 7.25 and Table 7.26.
Table 7.25 Set feature Register Definition
Features Code
*1
Description Default
03h
Set transfer mode based on value in Sector Count register
See Table 7.26.
05h
Enable Advanced Power management
*2
√
09h
Enable Address Offset Mode
*3
33h
Disable
retries
44h
Enable Vendor Unique ECC Byte Length(24 bytes) transfer
55h
Disable read look-ahead feature
66h
Disable reverting to power on defaults
√
77h
Disable
ECC
85h
Disable Advanced Power management
*2
88h
Enable
ECC
√
89h
Disable Address Offset Mode
*3
99h
Enable
retries
√
AAh
Enable read look-ahead feature
√
BBh
Enable 4 bytes ECC transfer
√
CCh
Enable reverting to power on defaults
02h
Enable write cache
√
82h
Disable write cache
*1
: If the code is not supported, the device returns Aborted Command Error.
*2
: See Sec. 7.2.2.3 Advanced Power Management for the details.
*3
: See Sec. 7.2.6 Address Offset Feature (Vendor Specific)for the details.
Table 7.26 Transfer Mode Code Definition
Sector Count
Register
Transfer Mode
2Xh
Multi-Word DMA Mode (X: 0, 1, 2):
0: Mode 0(4.1 MB/s), 1: Mode 1(13.3 MB/s), 2: Mode 2(16.6 MB/s)
4Xh
Ultra DMA Mode (X: 0, 1, 2, 3, 4, 5):
0: Mode 0(16.6 MB/s), 1: Mode 1(25.0 MB/s), 2: Mode 2(33.3 MB/s)
3: Mode 3(44.4 MB/s), 4: Mode 4(66.6 MB/s), 5: Mode 5(100.0 MB/s)