Figure 127. Individual Threshold Data Structure - IBM IC25N040ATCS04 - Travelstar 40 GB Hard Drive Specifications

13.32.3.2 Individual Thresholds Data Structure
The following defines the 12 bytes that make up the information for each Threshold entry in the Device
Attribute Thresholds Data Structure. Attribute entries in the Individual Threshold Data Structure are in the
same order and correspond to the entries in the Individual Attribute Data Structure.
Description
Attribute ID Number (01h to FFh)
Attribute Threshold (for comparison with
Attribute Values from 00h to FFh)
00h – "always passing" threshold value to
be used for code test purposes
01h – minimum value for normal operation
FDh – maximum value for normal operation
FEh – invalid for threshold value
FFh – "always failing" threshold value to
be used for code test purposes
Reserved (00h)
Total Bytes

Figure 127. Individual Threshold Data Structure

13.32.3.3 Attribute ID Numbers
Attribute ID Numbers supported by the device are the same as Attribute Values Data Structures.
13.32.3.4 Attribute Threshold
These values are preset at the factory and are not meant to be changeable. However, the host might use
the "S.M.A.R.T. Write Attribute Threshold" subcommand to override these preset values in the Threshold
sectors.
13.32.3.5 Data Structure Checksum
The Data Structure Checksum is the 2's compliment of the result of a simple 8-bit addition of the first 511
bytes in the data structure.
Travelstar 60GH & 40GN hard disk drive specifications
Byte
1
1
10
12
176
Offset Format
00h binary
01h binary
02h binary