User Manual

SCSI Commands Reference Manual, Rev. J 292
www.seagate.com Parameters for direct access devices
5. Parameters for direct access devices
5.1 Diagnostic parameters
5.1.1 Diagnostic page format and page codes for direct access devices
This subclause describes the diagnostic page structure and the diagnostic pages that are applicable to all SCSI devices.
Diagnostic pages specific to each device type are described in the command standard that applies to that device type.
A SEND DIAGNOSTIC command with a PF bit set to one specifies that the SEND DIAGNOSTIC parameter list consists of a single
diagnostic page and that the data returned by the subsequent RECEIVE DIAGNOSTIC RESULTS command that has the PCV bit set
to zero shall use the diagnostic page format defined in table 254. A RECEIVE DIAGNOSTIC RESULTS command with a PCV bit set
to one specifies that the device server return a diagnostic page using the format defined in table 254.
Each diagnostic page defines a function or operation that the device server shall perform as a result of a SEND DIAGNOSTIC
command or the information being returned as a result of a RECEIVE DIAGNOSTIC RESULTS command with the PCV bit equal to
one. The diagnostic parameters contain data that is formatted according to the page code specified.
PAGE CODE field
The PAGE CODE field identifies the diagnostic page (see table 255).
Table 254 Diagnostic page format
Bit
Byte
7 6 5 4 3 2 1 0
0
PAGE CODE
1
PAGE CODE SPECIFIC
2
(MSB)
PAGE LENGTH (N-3)
3
(LSB)
4
DIAGNOSTIC PARAMETERS
. . .
n