Spinpoint M9T Product Manual REV 1.0
61
Table 8-11 Set Features Register Definitions
Code
Description
02h
Enable Write Cache
03h
Set transfer mode based on value in Sector Count register
06h
Enable Power-Up in Standby Mode
07h
Power-Up in Standby feature set device spin up
10h
Enable use of SATA features
SC=02: DMA Setup FIS Auto Activate automation
SC=03: Device-initiated interface power state transition
SC=06: Software Settings Preservation
44h
Obsolete (Set VU ECC length)
55h
Disable read look-ahead feature
82h
Disable Write Cache
86h
Disable Power-Up in Standby Mode
90h
Disable use of SATA features
SC=02: DMA Setup FIS Auto Activate automation
SC=03: Device-initiated interface power state transition
SC=06: Software Settings Preservation
AAh
Enable read look-ahead feature
BBh
Obsolete (Set 4-byte ECC length)
D2h-DFh
VU Features
F0h-FFh
VU Features
When the drive receives this command, it checks the contents of the Feature register, clears BSY, and
generates an interrupt. If the value in the Feature register is not supported or is invalid, the drive posts an
Aborted Command error.
A host can choose the transfer mechanism by Set Transfer Mode and specifying a value in the Sector Count
register in feature 03. The upper 5 bits define the type of transfer, and the low order 3 bits encode the mode
value. Refer to the following table for details.
Table 8-12 Transfer Mode Values
Mode
Bits(7:3)
Bits(2:0)
PIO default mode
00000
000
PIO default mode, disable IORDY
00000
001
PIO flow control transfer mode
00001
mode
Multiword DMA mode
00100
mode
Ultra DMA mode
01000
mode
Mode = transfer mode number