Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
195
19.10.14.1 Background Control (Subpage 01h)
Table 161:Background Control (Subpage 01h)
Suspend On Log Full (S_L_FULL) bit set to zero allows background scans to continue if the results log (Log Sense
Page 15h) is full. S_L_FULL bit set to one will cause background scans to suspend when the log is full.
Log Only When Intervention Required (LOWIR) bit set to zero allows logging of all medium errors in the results log
(Log Sense Page 15h). When the LOWIR bit is set to one, only unrecovered medium errors will be logged.
EN_BMS (Enable Background Medium Scan) bit set to zero specifies that the background medium scan is disabled.
EN_BMS bit set to one specifies that background medium scan operations are enabled. If a background medium
scan is in progress when the EN_BMS bit is changed from one to zero, then the medium scan shall be suspended until
the EN_BMS bit is set to one, at which time the medium scan shall resume from the suspended location.
EN_PS (Enable Pre-Scan) bit set to zero specifies that the pre-scan is disabled. If a pre-scan operation is in progress
when EN_PS is changed from a one to a zero, then pre-scan is halted. An EN_PS bit set to one specifies that a pre-
scan operation is started after the next power-on cycle. Once this pre-scan has completed, another pre-scan shall not
occur unless the EN_PS bit is set to zero, then set to one, and another power-on cycle occurs.
Background Medium Scan Interval Time specifies the minimum time, in hours, between the end of one background
medium scan operation and the start of the next background medium scan operation. The BMS Interval Time shall
occur before the initial background medium scan operation is started.
Background Pre-Scan Time Limit specifies the maximum time, in hours, for a pre-scan operation to complete. If the
pre-scan operation does not complete within the specified time, then it is halted. A value of zero specifies an unlim-
ited time limit.
Minimum Idle Time Before Background Scan specifies the minimum time, in milliseconds, that the drive must be idle
before resuming a background media scan or pre-scan. A value of zero will be treated as the default value of 1.0 sec-
ond. Any value less than 100 milliseconds will be treated as 100 milliseconds. The internal timer granularity is 50
milliseconds.
Maximum Time To Suspend Background Scan specifies the maximum time, in milliseconds, that the drive should
delay before processing a new command while background scanning is in progress.
Byte BIT
76543210Default
0 PS SPF=1 Page Code = 1Ch DCh
1 Subpage Code = 01h 01h
2-3 Page Length = 0Ch 000Ch
4 Reserved = 0 S_L_Full LOWIR EN_BMS 01h
5 Reserved = 0 EN_PS 00h
6-7 Background Medium Scan Interval Time 00A8h
8-9 Background Pre-Scan Time Limit 0000h
10-11 Minumum Idle Time Before Background Scan 0000h
12-13 Maximum Time To Suspend Background Scan 0000h
14-15 Reserved = 0 0000h