Seagate ST3400071FC ユーザーズマニュアル

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NL35 Series FC Product Manual, Rev. D
65
9.5.10
Motor start controls
The drive’s motor is started according to the Start_1 and Start_2 signals described in Table 31. The state of 
these signals can be wired into the backplane socket or driven by logic on the backplane.
9.5.11
SEL_6 through SEL_0 ID lines
The SEL_6 through SEL_0 ID lines determine drive address, and, optionally, for an Enclosure Services Inter-
face. When the Parallel ESI line is high, the enclosure backpanel must provide address information on the SEL 
line. Refer to table 32 for a mapping of SEL to FC-AL physical addresses (AL_PA). You can think of the SEL 
lines as the equivalent of a backpanel logic plug. The drives does not provide pull up resistors on these lines. 
The backpanel is required to provide high and low inputs to the SEL_ID lines per the specifications in table 34
on page 67. 
Note.
Table 32 gives AL_PA values for each SEL value. The first entry in the table is SEL_ID 00. The last 
entry is SEL_ID 7D. SEL_ID 7E is AL_PA 00 which is not valid for an NL_Port, so is not included in 
the table. Also, SEL_ID 7Fh does map to a valid AL_PA; however, this value signals the drive that 
physical addresses are not being assigned using the SEL lines and that a “soft” address will be 
determined by FC-AL loop initialization.
When the Parallel ESI line is low, the enclosure backpanel logic switches to ESI mode if supported. There are 
two modes of ESI, seven bits of enclosure status and a bidirectional mode. ESI support and the mode are 
determined by the drive using a discovery process. Refer to the Fibre Channel Interface Manual for a descrip-
tion of ESI operation.
9.5.11.1
Parallel Enclosure Services Interface (ESI)
The parallel ESI line is an output from the drive. This line provides the enclosure with an indication of the 
present function of the SEL lines. A high level, the default state, indicates the drive requires address informa-
tion on the SEL lines. A low level indicates the drive is attempting an ESI transfer. The enclosure may not sup-
port ESI on any or all drive locations. It may only support the address function. Support of ESI is discovered by 
the drive. Refer to the Fibre Channel Interface Manual for a description of ESI operations.
Table 31: 
Motor start control signals
Case
Start_2
Start_1
Motor spin function
1
Low
Low
Motor spins up at DC power on.
2
High
Low
Motor spins up only when SCSI Start command is received.
3
Low
High
Motor spins up after a delay of 12 seconds times the modulo 8 value of 
the numeric SEL ID of the drive from DC power on.
4
High 
High
The drive will not spin up.