IBM Deskstar 120 GXP, Specifications

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10.1 PIO Data In commands
These commands are
!
Device Configuration Identify
!
Identify Device
!
Read Buffer
!
Read Long
!
Read Multiple
!
Read Sectors
!
S.M.A.R.T. Read Attribute Values
!
S.M.A.R.T. Read Attribute Thresholds
!
S.M.A.R.T. Read Log Sector
Execution includes the transfer of one or more 512 byte (>512 bytes on Read Long) sectors of data from
the device to the host.
1. The host writes any required parameters to the Features, Sector Count, Sector Number, Cylinder,
and Device/Head Registers.
2. The host writes the command code to the Command Register.
3. For each sector of data to be transferred
a. The device sets BSY=1 and prepares for data transfer.
b. When a sector of data is available for transfer to the host, the device sets BSY=0, sets DRQ=1,
and interrupts the host.
c. In response to the interrupt the host reads the Status Register.
d. The device clears the interrupt in response to the Status Register being read.
e. The host reads one sector of data via the Data Register.
f. The device sets DRQ=0 after the sector has been transferred to the host.
4. For the Read Long command
a. The device sets BSY=1 and prepares for data transfer.
b. When the sector of data is available for transfer to the host, the device sets BSY=0, sets DRQ=1,
and interrupts the host.
c. In response to the interrupt the host reads the Status Register.
d. The device clears the interrupt in response to the Status Register being read.
e. The host reads the sector of data including ECC bytes via the Data Register.
f. The device sets DRQ=0 after the sector has been transferred to the host.
The Read Multiple command transfers one block of data for each interrupt. The other commands transfer
one sector of data for each interrupt.
Note that the status data for a sector of data is available in the Status Register before the sector is trans-
ferred to the host.
Deskstar 120GXP hard disk drive specifications
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