74 |
| Barracuda 36ES2 Product Manual, Rev. B | ||
Table 17: Disc drive SCSI timing (Continued) |
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| Waveform |
| Waveform |
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Description | symbol [1] |
| table [1] | Typical timing |
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Data In Byte Transfer (parameter) | T24 |
| 0.04 ∝s | |
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Data Out Byte Transfer (parameter) | T25 |
| 0.04 ∝s | |
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Next Data In Byte Access (parameter) | T26 |
| 0.12 ∝s | |
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Next Data Out Byte Access (parameter) | T27 |
| 0.12 ∝s | |
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Data In Byte Transfer (media) [2] | T28 |
| 0.04 ∝s | |
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Data Out Byte Transfer (media) [2] | T29 |
| 0.04 ∝s | |
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Next Data In Byte access (media [2] | T30 |
| 0.12 ∝s | |
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Next Data Out Byte access (media [2] | T31 |
| 0.12 ∝s | |
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MSG IN Byte Transfer | T32 |
| 0.04 ∝s | |
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MSG OUT Byte Transfer | T33 |
| 0.04 ∝s | |
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STATUS Byte Transfer | T34 |
| 0.04 ∝s | |
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Synchronous Data Transfer Characteristics: |
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Request Signal Transfer Period [3] | – |
| – | various (800 ns max) |
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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.
9.11Drive activity LED
The following table provides drive activity LED status.
Table 18: Drive activity LED status
Spindle status | Command status | LED status |
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Spinning up with DC power applied | N/A | On until spinup is complete |
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Spun down | Start Unit | On while processing the command |
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Powered down by removal of DC power | N/A | Off due to absence of power |
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Spun up | Stop Unit | On while processing the command |
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Spun down | No command activity | Off |
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Spun down | Write/Read Buffer | On while processing the command |
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Spun down | SCSI Bus Reset | On while processing the reset |
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Spun down | Test Unit Ready | On while processing the command |
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Spun up | No command activity | Off |
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Spun up | Write/Read | On while processing the command |
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Spun up | SCSI Bus Reset | On while processing the reset |
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Spun up | Test Unit Ready | On while processing the command |
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Spun up | Format with Immediate option on | On while the command is initially processed |
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Spun up | Format without Immediate | LED toggles on/off on each cylinder boundary |
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