Lba High Register; Lba Low Register; Lba Mid Register; Sector Count Register - Hitachi HTS421212H9AT00 - Travelstar 120 GB Hard Drive Specifications

10.9 LBA High Register

This register is command specific. This is used with the Set Features command, S.M.A.R.T. Function Set com-
mand and Format Unit command.
When 48-bit addressing commands are used, the "most recently written" content contains LBA Bits 16-23, and the
"previous content" contains Bits 40-47. The 48-bit Address feature set is described in Section 11.15 "48-bit
Address Feature Set," on page 89.

10.10 LBA Low Register

This register contains Bits 0-7. At the end of the command, this register is updated to reflect the current
LBA Bits 0-7.
When 48-bit commands are used, the "most recently written" content contains LBA Bits 0-7, and the "previous
content" contains Bits 24-31.

10.11 LBA Mid Register

This register contains Bits 8-15. At the end of the command, this register is updated to reflect the current LBA
Bits 8-15.
When 48-bit addressing commands are used, the "most recently written" content contains LBA Bits 8-15 and the
"previous content" contains Bits 32-39.

10.12 Sector Count Register

This register contains the number of sectors of data requested to be transferred on a read or write operation between
the host and the device. If the value in the register is set to 0, a count of 256 sectors (in 28-bit addressing) or 65,536
sectors (in 48-bit addressing) is specified.
If the register is zero at command completion, the command was successful. If not successfully completed, the reg-
ister contains the number of sectors which need to be transferred in order to complete the request.
The contents of the register are defined otherwise on some commands. These definitions are given in the command
descriptions.

10.13 Status Register

Table 46: Status Register

7 6 5 4 3 2 1 0
BSY DRDY DF DSC DRQ CORR IDX ERR
This register contains the device status. The contents of this register are updated whenever an error occurs and at
the completion of each command.
If the host reads this register when an interrupt is pending, it is considered to be the interrupt acknowledge. Any
pending interrupt is cleared whenever this register is read.
If BSY=1, no other bits in the register are valid.
Travelstar 4K120 Hard Disk Drive Specification
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