Seagate Spinpoint M8, Product Manual

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Spinpoint M8 Product Manual REV 2.6
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In LBA mode the sectors on the device are assumed to be linearly mapped with an initial definition of: LBA
0 = (Cylinder 0, head 0, and sector 1). Irrespective of translate mode geometry set by the host, the LBA
address of a given sector does not change:
6.3.2 I/O Register - Address
The communication to or from drive is through the SATA interface. To the host system the SATA drive
emulates a parallel ATA drive. As such, the following registers are not accessed directly host to drive. The
registers are set through the Serial Interface.
The Control Block registers are used for drive control and to post-alternate status. I/O port function and its
selection address are tabulated.
I/O registers
Command Block registers
When read When written
Data Data
Error Features Current
Features Previous
Sector Count Current
Sector Count Previous
Sector Count Current
Sector Count Previous
LBA Low Current
LBA Low Previous
LBA Low Current
LBA Low Previous
LBA Mid Current
LBA Mid Previous
LBA Mid Current
LBA Mid Previous
LBA High Current
LBA High Previous
LBA High Current
LBA High Previous
Device Device
Status Command
Control Block registers
Alternate Status Device Control
6.3.3 Control Block Register Descriptions
6.3.3.1 Alternate Status Register (ex. 3F6h)
This register contains the same information as the Status register in the Command Block register. The only
difference is that reading this register does not imply interrupt acknowledgment nor does it clear a pending
interrupt.
7 6 5 4 3 2 1 0
BSY DRDY # # DRQ Obsolete Obsolete ERR
NOTE : See 6.3.4.10 for definitions of the bits in this register.