IBM IC35L020 - Deskstar 20 GB Hard Drive Specifications page 190

Output Parameters To The Drive
Sector Count This is a Time-out Parameter. If the Sector Count is 0, then the automatic power
down sequence is disabled. If the Sector Count is non-zero, then the automatic
power down sequence is enabled. The time-out intervals are shown as follows:
When the automatic power down sequence is enabled, the drive will enter
Standby mode automatically if the time-out interval expires with no drive access
from the host. The time-out interval will be reinitialized if there is a drive access
before the time-out interval expires.
Deskstar 60 GXP Hard disk drive specification
Value Time-out
-------- ---------------------
0 Timer disabled
1-240 Value * 5 seconds
241-251 Value-240) * 30 minutes
252 21 minutes
253 8 hours
254 21 minutes 10 seconds
255 21 minutes 15 seconds
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