IBM Deskstar 120 GXP, Specifications

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9.0 General operation
9.1 Reset response
There are three types of resets in ATA:
Power On Reset (POR). The device executes a series of electrical circuitry diagnostics, spins up the
HDA, tests speed and other mechanical parameters, and sets default values.
Hard Reset (Hardware Reset). RESET- signal is negated in ATA Bus. The device resets the
interface circuitry as well as Soft Reset.
Soft Reset (Software Reset). SRST bit in the Device Control Register is set and then is reset. The
device resets the interface circuitry according to the Set Features requirement.
The actions of each reset is shown in the following figure.
(4) (4) (5) Power mode
X X O Disable Standby timer
(3) (3) O
Reverting programmed parameters to default
!
Number of CHS (set by Initialize Device Parameter)
!
Multiple mode
!
Write Cache
!
Read look-ahead
!
ECC bytes
O O O PDIAG handshake
X O O DASP handshake
O O O Initialization of registers (2)
X X O Spinning spindle
X X O Internal diagnostic
X X O Initialization of hardware
(1) (1) – Aborting Device interface
O O – Aborting Host interface
Soft Reset Hard Reset POR
O - execute X - not execute
Notes:
(1) Execute after the data in write cache has been written.
(2) Default value on POR is shown in Figure 76 on page 74.
(3) The Set Features command with Feature register = CCh enables the device to revert these para-
meters to the power on defaults.
(4) In the case of Sleep mode the device goes to Standby mode. In other cases the device does not
change current mode.
(5) Idle when Power-Up in Standby feature set is disabled. Standby when Power-Up in Standby
feature set is enabled.
Figure 75. Reset Response Table
Deskstar 120GXP hard disk drive specifications
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