Seagate ST31200N, Руководство по эксплуатации продукта

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Product Manual - Hawk 1LP Family SCSI-2 (Volume 1), Rev. C 11
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5.3.1 Notes for sections 5.2 and 5.3.
[1] Execution time measured from receipt of the last Byte of the Command Descriptor Block (CDB) to the
request for a Status Byte Transfer to the Initiator (excluding connect/disconnect).
[2] Maximum times are specified over the worst case conditions of temperature, voltage margins and drive
orientation. When comparing specified seek times, care should be taken to distinguish between typical
seek times and maximum seek times. The best comparison is obtained by system benchmark tests
conducted under identical conditions. Maximum times do not include error recovery.
[3] Typical Seek values are measured under nominal conditions of temperature, voltage, and horizontal
orientation as measured on a representative sample of drives.
[4] Assumes no errors and no sector has been relocated.
[5] Rate measured from the start of the first sector transfer to or from the Host.
[6] Assumes the Initiator immediately sends Write Data to the drive when requested.
[7] Command execution requires a data transfer phase (data to or from the disc media). Assumes the initiator
is instantly ready to send or receive the data when the drive generates first request for a data byte transfer,
and assumes an average data transfer rate between the drive and the Initiator as specified in section 5.3.
[8] All performance characteristics assume that automatic adaptive temperature compensation is not in
process when the SCSI command is received. A SCSI command being executed is not interrupted for
automatic adaptive temperature compensation. If adaptive thermal compensation is in process when a
SCSI command is received, the command is queued until the compensation for the specific head being
compensated completes. When compensation completes for the specific head being compensated, the
first queued SCSI command is executed. When execution of the first queued command is complete, the
drive continues the compensation for the remaining head(s). The above procedure continues until
compensation for all heads is completed, or until one minute has elapsed. If the compensation for all heads
is not complete in one minute the drive performs compensation for all of the remaining heads sequentially
without any interruption. The drive initiates an automatic adaptive temperature compensation cycle
approximately one minute after power-on, and approximately once every 10 minutes thereafter. Automatic
adaptive temperature compensation takes less than 0.1% of bus time. Automatic temperature compen-
sation also occurs at other times, but should be transparent to the user (e.g., during format, Rezero
Command, at spindle up, during read error recovery, and during Reassign Block functions). A Rezero
command can be used to reset the thermal compensation timer back to its start so that the host can know
when the next interruption for thermal compensation will occur.
5.4 Start/stop time
After DC power has been applied, all drive types except the 1.0 MB RAM Option becomes ready within 20
seconds (15 seconds typical) if the Motor Start option is disabled (i.e. the motor starts as soon as the power
has been applied). After DC power has been applied, the drive with 1.0 MB RAM option becomes ready within
35 seconds (25 seconds typical) if the Motor Start option is disabled (i.e. the motor starts as soon as the power
has been applied). During this time the drive responds to some commands over the SCSI interface* in less
than 3 seconds. Stop time is less than 20 seconds from removal of DC power.
If the Motor Start Option is enabled, the internal controller accepts the commands listed in the SCSI Interface
Product Manual* less than 3 seconds after DC power has been applied. After the Motor Start Command has
been received the drive becomes ready for normal operations within 13 seconds typically. The Motor Start
Command can also be used to command the drive to stop the spindle*.
There is no power control switch on the drive.
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*SCSI commands are described in the SCSI Interface Product Manual Volume 2, P/N 77738479