HGST Travelstar 7K500 BE, 250GB 0A79102 User Manual
Product codes
0A79102
7K500 OEM Specification
Page 51 of 176
12
12
12
12 General Operation Descriptions
General Operation Descriptions
General Operation Descriptions
General Operation Descriptions
12.1
12.1
12.1
12.1 Reset Response
Reset Response
Reset Response
Reset Response
There are three types of reset in ATA as follows:
Power On Reset (POR)
The device executes a series of electrical circuitry diagnostics, spins up the HDA,
tests speed and other mechanical parametric, and sets default values.
tests speed and other mechanical parametric, and sets default values.
COMRESET
COMRESET is issued in Serial ATA bus.
The device resets the interface circuitry as well as Soft Reset.
The device resets the interface circuitry as well as Soft Reset.
Soft Reset (Software Reset)
SRST bit in the Device Control Register is set, then is reset.
The device resets the interface circuitry according to the Set Features requirement.
The device resets the interface circuitry according to the Set Features requirement.
The actions of each reset are shown in “Table 29 Reset Response Table” on Page 51
POR
COMRESET
Soft Reset
Aborting Host interface
-
o
o
Aborting Device operation
-
(*1)
(*1)
Initialization of hardware
O
x
x
Internal diagnostic
O
x
x
Starting spindle motor
(*5)
x
x
Initialization of registers (*2)
O
o
o
Reverting programmed parameters to default
O
(*6)
(*3)
- Number of CHS (set by Initialize Device Parameter)
- Multiple mode
- Write cache
- Read look-ahead
- ECC bytes
- Volatile max address
Power mode
(*5)
(*4)
(*4)
Reset Standby timer value
o
o
x
O ---- execute
X ---- not execute
X ---- not execute
Note.
(*1) Execute after the data in write cache has been written.
(*1) Execute after the data in write cache has been written.
(*2) Default value on POR is shown in “
Table 30 Default Register Values” on Page 52.
(*3) The Set Features command with Feature register = CCh enables the device to
revert these parameters to the power on defaults.
(*4) In the case of sleep mode, the device goes to standby mode. In other case,
the device does not change current mode.
(*5) According to the initial power mode selection.
(*6) See 12.14
Software Setting Preservation Feature Set.
Table 29 Reset Response Table
12.1.1
12.1.1
12.1.1
12.1.1
Register Initialization
Register Initialization
Register Initialization
Register Initialization
After power on, COMRESET, or software reset, the register values are initialized as shown in the following table.