Device Configuration Freeze Lock (Subcommand C1H); Device Configuration Identify (Subcommand C2H); Device Configuration Set (Subcommand C3H) - IBM IC25N040ATCS04 - Travelstar 40 GB Hard Drive Specifications

13.2.2 DEVICE CONFIGURATION FREEZE LOCK (subcommand C1h)

The DEVICE CONFIGURATION FREEZE LOCK command prevents accidental modification of the Device
Configuration Overlay settings. After successful execution of a DEVICE CONFIGURATION FREEZE
LOCK command, all DEVICE CONFIGURATION SET, DEVICE CONFIGURATION FREEZE LOCK,
DEVICE CONFIGURATION IDENTIFY, and DEVICE CONFIGURATION RESTORE commands are
aborted by the device. The DEVICE CONFIGURATION FREEZE LOCK condition shall be cleared by a
power-down. The DEVICE CONFIGURATION FREEZE LOCK condition shall not be cleared by hardware
or software reset.

13.2.3 DEVICE CONFIGURATION IDENTIFY (subcommand C2h)

The DEVICE CONFIGURATION IDENTIFY command returns a 512 byte data structure via PIO data-in
transfer. The content of this data structure indicates the selectable commands, modes, and feature sets
that the device is capable of supporting. If a DEVICE CONFIGURATION SET command has been issued
reducing the capabilities, the response to an IDENTIFY DEVICE or IDENTIFY PACKET DEVICE com-
mand will reflect the reduced set of capabilities, while the DEVICE CONFIGURATION IDENTIFY
command will reflect the entire set of selectable capabilities.
The format of the Device Configuration Overlay data structure is shown on the next page.

13.2.4 DEVICE CONFIGURATION SET (subcommand C3h)

The DEVICE CONFIGURATION SET command allows a device manufacturer or a personal computer
system manufacturer to reduce the set of optional commands, modes, or feature sets supported by a
device as indicated by a DEVICE CONFIGURATION IDENTIFY command. The
DEVICE CONFIGURATION SET command transfers an overlay that modifies some of the bits set in
words 63, 82, 83, 84, and 88 of the IDENTIFY DEVICE command response. When the bits in these words
are cleared, the device no longer support the indicated command, mode, or feature set. If a bit is set in the
overlay transmitted by the device that is not set in the overlay received from a DEVICE CONFIGURATION
IDENTIFY command, no action is taken for that bit.
The format of the overlay transmitted by the device is described in the table on the next page. The
restrictions on changing these bits is described in the text following that table. If any of the bit modification
restrictions described are violated or any setting is changed with DEVICE CONFIGURATION SET
command, the device shall return command aborted. At that case, error reason code is returned to sector
count register, invalid word location is returned to cylinder high register, and invalid bit location is returned
to cylinder low register. The Definition of error information is shown on the next page.
ERROR INFORMATION EXAMPLE 1:
After establishing a protected area with SET MAX address, if a user attempts to change maximum LBA
address (DC SET or DC RESTORE), the device aborts that command and returns error reason code as
below.
Cylinder high :
Cylinder low :
Sector count :
03h = word 3 is invalid
00h this register is not assigned in this case
06h = Protected area is now established
Travelstar 60GH & 40GN hard disk drive specifications
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