Текст страницы
12.49.6.5 Enable the EPC feature subcommand (4h)
Table 211 Enable the EPC feature subcommand
Command Block Normal Outputs
Command Block Command Input
Register
7
6
5
4
3
2
1
0
Register
7
6
5
4
3
2
1
0
Data
-
-
-
-
-
-
-
-
Data
-
-
-
-
-
-
-
-
Feature
0
1
0
0
1
0
1
0
Error
…See Below…
Sector Count
-
-
-
-
-
-
-
-
Sector Count
-
-
-
-
-
-
-
-
Sector Number
-
-
-
-
0
1
0
0
Sector Number
-
-
-
-
-
-
-
-
Cylinder Low
-
-
-
-
-
-
-
-
Cylinder Low
-
-
-
-
-
-
-
-
Cylinder High
-
-
-
-
-
-
-
-
Cylinder High
-
-
-
-
-
-
-
-
Device/Head
1
-
1
D
-
-
-
-
Device/Head
-
-
-
-
-
-
-
-
Command
1
1
1
0
1
1
1
1
Status
…See Below…
Error Register
Status Register
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
CRC UNC 0
IDN 0
ABT T0N AMN
BSY RDY DF
DSC DRQ COR IDX ERR
0
0
0
0
0
V
0
0
0
V
0
-
-
0
-
V
On successful completion of this EPC subcommand, the device:
a) enables the EPC feature set;
b) sets IDENITFY DEVICE data Word 120 bit 7 to one; and
c) disables the APM feature set.
d) if the Saved Timer Setting field is cleared to zero, then:
copy the value of the Default Timer Setting to the Current Timer Setting; and
e) if the Saved Timer Setting field is non-zero, then:
copy the value of the Saved Timer Setting to the Current Timer Setting; and
f) if the Current Timer Setting field is non-zero and the Current Timer Enabled is set to one,
then initialize and start the timer.
If the EPC feature set is enabled, then the EPC feature set remains enabled across all resets (i.e., power-on reset,
hardware reset, and software reset).
Output Parameters To The Device
Sector Number Bit
Description
7-4
Reserved
3-0
4h Enable the EPC feature subcommand (See Table 65)
Error Output
If the Extended Power Condition feature set is not supported then the device returns command aborted.
288
Hard Disk Drive Specification