Chapter 7 Sata Ii Feature Set; N Ative C Ommand Q Ueuing (Ncq) - Samsung SpinPoint M9T Product Manual

CHAPTER 7
This section describes the SATA II feature set supported in the Samsung Spinpoint M9T drive.
7.1 Device Activity Signal
Spinpoint M9T implemented the Device Activity Signal on the SATA power connector pin-11. The
implementation is based on the SATA II specification. This activity signal is used for indicating the drive
activities, including the queued and non-queued commands. For the host can use this signal to indicate the
command activity.
7.2 Staggered Spin-up Disable Control
Spinpoint M9T implemented the staggered spin-up disable control by using the SATA power connector pin-
11. This pin is multiplexed with the Device Activity Signal support. On power up this pin is used for the spin-
up control. After the device is connected with the host, this pin is used for the Device Activity.
Before the device spins up its media, devices that support staggered spin-up disable control shall detect
whether pin 11 is asserted low by the host. If pin 11 is asserted low the device shall disable staggered spin-up
and immediately initiate media spin-up. If pin 11 is not connected in the host (floating), devices that support
staggered spin-up disable through pin 11 shall enable staggered spin-up.
7.3 Auto-Activate in DMA Setup FIS
Spinpoint M9T implemented the option for the Auto-Activate in DMA Setup FIS. With this feature enabled,
the DMA Setup FIS is automatically activated. This automation help improve the efficiency of the DMA data
transfer. This feature can be enabled by the SATA Set Feature command.
If the Set Feature is not issued, the DMA Setup FIS is not automatically activated.
7.4 Native Command Queuing (NCQ)
Spinpoint M9T supports the NCQ feature of the SATA II command interface. The NCQ feature is unique in
the SATA II implementation which helps device improve the system performance. The implementation is
fully compliant with the SATA II specification.
The drive implements the NCQ with its proprietary hardware and firmware to enhance the command
performance. The NCQ hardware automatically receives the NCQ commands from the host. The hardware
verifies the duplication of the tag number and report tag duplicated error immediately. The automation of the
hardware and firmware handles the NCQ command from its reception to the reordering and command
execution. The drive intelligent firmware is capable of sorting the physical address of the incoming
commands and decides the execution order for the best performance.
Spinpoint M9T Product Manual REV 1.0
SATA II FEATURE SET
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