Drive Activity Led - Seagate ST318404LW Product Manual

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Table 18: Disc drive SCSI timing (Continued)
These values are not current Cheetah 18XL values, but are listed for information only.
Description
Next CDB Byte Access (Byte 10 of 10)
Data In Byte Transfer (parameter)
Data Out Byte Transfer (parameter)
Next Data In Byte Access (parameter)
Next Data Out Byte Access (parameter)
Data In Byte Transfer (media) [2]
Data Out Byte Transfer (media) [2]
Next Data In Byte access (media [2]
Next Data Out Byte access (media [2]
MSG IN Byte Transfer
MSG OUT Byte Transfer
STATUS Byte Transfer
Synchronous Data Transfer Characteristics:
Request Signal Transfer Period [3]
Notes.
[1] See the SCSI Interface Product Manual, part number 75789509, Timing examples section.
[2] Maximum SCSI asynchronous interface transfer rate is given in Section 4.2.3 of this manual.
[3] Synchronous Transfer Period is determined by negotiations between an Initiator and a Drive. The Drive is
capable of setting periods as given in Section 9.5. See also the Synchronous data transfer section and the
Extended messages section of the SCSI Interface Product Manual, for a description of synchronous data
transfer operation.
9.11

Drive activity LED

The following table provides drive activity LED status.
Table 19: Drive activity LED status
Spindle status
Spinning up with DC power applied
Spun down
Powered down by removal of DC power N/A
Spun up
Spun down
Spun down
Spun down
Spun down
Spun up
Spun up
Spun up
Spun up
Spun up
Spun up
Waveform
symbol [1]
T23.10.10
T24
T25
T26
T27
T28
T29
T30
T31
T32
T33
T34
–
Command status
N/A
Start Unit
Stop Unit
No command activity
Write/Read Buffer
SCSI Bus Reset
Test Unit Ready
No command activity
Write/Read
SCSI Bus Reset
Test Unit Ready
Format with Immediate option on On while the command is initially processed
Format without Immediate
Cheetah 18XL Product Manual, Rev. A
Waveform
table [1] Typical timing
0.12 µs ±1 µs
4.5-4
0.04 µs
4.5-12
0.04 µs
4.5-13
0.12 µs
4.5-12
0.12 µs
4.5-13
0.04 µs
4.5-12
0.04 µs
4.5-13
0.12 µs
4.5-12
0.12 µs
4.5-13
0.04 µs
4.5-5,7,8,14,15
0.04 µs
4.5-2
0.04 µs
4.5-5,8,15
– various (800 ns max)
LED status
On until spinup is complete
On while processing the command
Off due to absence of power
On while processing the command
Off
On while processing the command
On while processing the reset
On while processing the command
Off
On while processing the command
On while processing the reset
On while processing the command
LED toggles on/off on each cylinder boundary