Deskstar T7K500 Hard Disk Drive Specification
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10.3 Diagnostic and Reset considerations
For each Reset and Execute Device Diagnostic, the diagnostic is done as follows:
In each case – Power On Reset [Hard Reset], Soft Reset, and the Execute Device Diagnostic command – the
Device 0 Error register value is interpreted using the table below.
The "x" indicates the appropriate Diagnostic Code for the Power on, RESET-, Soft Reset, or Device Diagnostic
error.
Power On Reset DASP– is read by Device 0 to determine if Device 1 is present. If Device 1 is present,
Device 0 shall read PDIAG– to determine when it is valid to clear the BSY bit and
whether Device 1 has powered on or reset without error, otherwise Device 0 clears the
BSY bit whenever it is ready to accept commands. Device 0 may assert DASP– to
indicate device activity.
Hard Reset,
Soft Reset
If Device 1 is present, Device 0 shall read PDIAG– to determine when it is valid to clear
the BSY bit and whether Device 1 has reset without any errors; otherwise, Device 0 shall
simply reset and clear the BSY bit. DASP– is asserted by Device 0 (and Device 1 if it is
present) in order to indicate device active.
Execute Device
Diagnostic
If Device 1 is present, Device 0 shall read PDIAG– to determine when it is valid to clear
the BSY bit and if Device 1 passed or failed the EXECUTE DEVICE DIAGNOSTIC
command; otherwise, Device 0 shall simply execute its diagnostics and then clear the
BSY bit. DASP– is asserted by Device 0 (and Device 1 if it is present) in order to
indicate that the device is active.
Table 59: Reset error register values
Device 1 present? PDIAG- Asserted? Device 0 Passed Error Register
Yes Yes Yes 01h
Yes Yes No 0xh
Yes No Yes 81h
Yes No No 8xh
No (not read) Yes 01h
No (not read) No 0xh