Seagate Spinpoint M8, Руководство по эксплуатации продукта

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Spinpoint M8 Product Manual REV 2.6
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DATA CHARACTER- A data character is a combination of a byte value with the control variable equal to D.
DWORD- A Dword is thirty-two (32) bits of data. A Dword may be represented as 32 bits, as two adjacent
words, or as four adjacent bytes. When shown as bits the least significant bit is bit 0 and most significant bit is
bit 31. The most significant bit is shown on the left. When shown as words the least significant word (lower)
is word 0 and the most significant (upper) word is word 1. When shown as bytes the least significant byte is
byte 0 and the most significant byte is byte 3.
DWORD SYNCHRINIZATION- The state in which a receiver has recognized the comma sequence and is
producing an aligned data stream of Dwords (four contiguous bytes) from the zero-reference of the comma
character.
ENCODED CHARACTER- An encoded character is the output of the 8b/10b encoder – the result of
encoding a character. An encoded character consists of 10 bits, where bit 0 is the most significant bit and bit
9 is the least significant. The bits in an encoded character are symbolically referred to as “
abcdeifghj ” where
“a” corresponds to bit 0 and “j” corresponds to bit 9.
ELASTICITY BUFFER- The elasticity buffer is a portion of the receiver where character slipping and/or
character alignment is performed.
FIRST PARTY DMA ACCESS - First-party DMA access is a method by which a device accesses host
memory.
FIRST PARTY DMA MODE (FPDMA) - A device which is operating in First-party DMA mode uses First-
party DMA as a primary communications method between the host and the device. A software driver uses
legacy mode commands to place the device into First-party DMA mode of operation. The legacy-mode
command places the device into the First-party DMA mode of operation and the command protocol used between
a device and host when in First-party DMA mode are not specified by this specification.
FIRST DATA PHASE - The FPDMA Data Phase is the period from the reception of a DMA Setup FIS until
either the exhaustion of the associated data transfer count or the assertion of the ERR bit in the shadow Status
register.
FIS- Stands for Frame Information Structure.
FRAME UNFIORMATION STRUCTURE- The user payload of a frame, does not include the SOF, CRC,
and EOF delimiters.
Frame- A frame is an indivisible unit of information exchanged between a host and device. A frame consists
of a SOF primitive, a Frame Information Structure, a CRC calculated over the contents of the FIS, and an
EOF primitive-
LEGACY M ODE - Legacy m o d e is the mode of operation w h i c h provides s o f tw a r e - transparent
communication of commands and status between a host and device using the ATA Command Block and
Control Block registers.
LEGAL CHARACTER- Legal character is one for which there exists a valid decoding, either into the data
character or control character fields. Due to running disparity constraints not all 10-bit combinations result in a
legal character. Additional usage restrictions in Serial ATA result in a further reduction in the SATA
defined control character space.
OOB SIGNAL DETECTOR -This block decodes Out of Band signal from the high speed input signal path.