Seagate Fibre Channel Interface - Manual (Page 318)

304 Fibre Channel Interface Manual, Rev. D
12.47 Send Diagnostic command
This command requests that the disc drive perform diagnostic tests on itself, or perform other optional opera-
tions. Table 205 shows the format of the Send Diagnostic command as implemented by the disc drive. When
the Self Test bit is zero, this command is usually followed by a Receive Diagnostic Results command and a
subsequent data transfer that returns data to the initiator. Using this latter procedure of Send Diagnostic/
Receive Diagnostic Results commands the initiator can ask the drive to return a list of optional operations it
supports (see Table 208) and then request a supported additional operation. The disc drive supports the pages
listed in Table 192 (see page 288).
For systems which support disconnection, the disc drive will disconnect while executing this command.
Field definitions (listed alphabetically)
Control
See Control Bytes in Section 11.2.1.6.
DEVOFL (SCSI Device Off Line)
1
Enables diagnostic operations that may adversely affect operations to other Logic Units on the same target. This bit
is not interpreted by the disc drive.
Parameter List Length
The length (in bytes) of the parameter list that is transferred during the data transfer.
The disc drive presently supports the pages listed in Table 206. If the initiator transfers more bytes than the disc drive sup-
ports, the disc drive rejects the command.
00h
No additional parameter pages to be sent with this command (this is not considered an error).
04h The length value sent when the initiator sends Page 00h (see Table 208).
06h The value sent from page A0h (see Table 210).
0Eh The value sent from Page 40h is sent (see Table 209).
Table 205: Send Diagnostic command (1Dh)
Bit
Byte
7 6 5 4 3 2 1 0
0 0 0 0 1 1 1 0 1
1 Self-Test Code PF Rsvd Self-Test DEVOFL Unit OFL
2 Reserved
3 (MSB)
Parameter List Length
4 (LSB)
5
Control
1Dh
Table
number
205
205
205