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Output Parameters To The Device
Feature Current
Subcommand (bits 3-0)
When bits (3:0) is 1h, Deadline Handling Subcommand.
WDNC(bits 4)
If the WDNC (Write Data Not Continue) bit is cleared to zero, then the device allows
WRITE FPDMA QUEUED command completion times to exceed what the ICC
parameter specified. If the WDNC bit is set to one, then all WRITE FPDMA QUEUED
commands are completed by the time specified by the ICC timer value, otherwise the
device returns command aborted for all outstanding commands. WDNC is only
applicable to WRITE FPDMA QUEUED commands with PRIO is set to 01b
(Isochronous – deadline dependent priority)
RDNC(bits 5)
If the RDNC (Read Data Not Continue) bit is cleared to zero, then the device allows
READ FPDMA QUEUED command completion times to exceed what the ICC
parameter specified. If the RDNC bit is set to one, then all READ FPDMA QUEUED
commands are completed by the time specified by the ICC timer value, otherwise the
device returns command aborted for all outstanding commands. RDNC is only
applicable to READ FPDMA QUEUED commands with PRIO is set to 01b
(Isochronous – deadline dependent priority)
Count
TAG (bits 7-3)
The TAG value is assigned to be different from all other queued commands. The value
does not exceed the maximum queue depth specified by the Word 75 of the Identify
Device information.
Sector Count Previous
Sector Number Current
Cylinder Low Current
Cylinder Low Previous
Cylinder High Current
Cylinder High Previous
Device/Head
Input Parameters From The Device
Sector Number (HOB=0)
Sector Number (HOB=1)
Cylinder Low (HOB=0)
Cylinder Low (HOB=1)
Cylinder High (HOB=0)
Cylinder High (HOB=1)
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Hard Disk Drive Specification