Intel RAID Controllers Alert Code Decoding White Paper

Intel® RAID Controllers: SAS Software Stack Appendix A

Revision 1.0

bit→

↓byte

7 6 5 4 3 2 1 0

12 Additional Sense Code

13 Additional Sense Code Qualifier

14 Field Replaceable Unit Code

Through

SKSV Sense Key Specific

Through

254

Additional Sense Bytes

The bytes required to decode an error message are Error Code, Sense Key, Additional Sense

Code, and Additional Sense Code Qualifier.

1.8 The Error Code

The Error Code (Byte 0) for an unexpected sense code is usually 70. Sometimes this byte

contains F0 instead because the 7

bit of the Byte 0 is valid, e.g., 0xF0 = 0x70 | 0x80, 0x70

indicates the current error on the target device and 0x80 indicates that the field contains valid

information.

1.9 The Sense Key, Additional Sense Code, and Additional Sense Code

Qualifier

The Sense Key (SK) (byte 2) is a basic error code and provides error category information. It is

necessary to check the Additional Sense Code (ASC) (byte 12) and the Additional Sense Code

Qualifier (ASCQ) (Byte 13) for additional information.

The information contained in the CDB, the SK, the ASC and the ASCQ provides information

about the error and failure mode.

In the earlier error message example the CDB (CDB = 0x2a 0x00 0x00 0x02 0xf2

0x00 0x00 0x00 0x80 0x00) was decoded as a WRITE command. The sense code

portion of this error message is shown below.

Byte

Sense=

0xf0

0x00

0x0b

0x00 0x02 0xf2 0x2d 0x0a 0x00 0x00 0x00 0x00

0x4b 0x05

0x00 0x00 0x00 0x00

Note the color code for Error Code, Sense Key , Additional Sense Code, and Additional Sense

Code Qualifier bytes.

The Error Code at Byte0 indicates that an error occurred and the sense message contains

usable information.

Sense Key at Byte2 is 0B and indicates that a command was aborted by the device.

ASC at Byte 12 is 4B and the ASCQ at Byte 13 is 05, which indicates that there was a Data

Phase Error - DATA OFFSET ERROR.