Emulex MD21/S2, Техническое руководство

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Controller Reset/Power üp Initialization
After this sequence is complete, the first command sent by an
Initiator is terminated with a CHECK status and a UNIT
ATTENTION Sense Key, For more information, see subsection 5.5,
SCSI Error Conditions, in the Emulex SCSI Disk Controller
Programming Reference Manual (manual number MD2352501).
Until the drives have been spun up, any command sent by an
initiator which accesses the media is terminated with a CHECK
status and a DRIVE NOT READY sense key.
After the drive has spun up, the first commmand sent by an
initiator which accesses the media loads the SAVED MODE sense
parameters. Prior to the drive being spun up, if an initiator
requests the current MODE SENSE parameters, the controller
returns the default MODE SENSE parameters. An initiator should
not request the MODE SENSE parameters until the drive is spun
up.
6.3 SELF-TEST MODES
The MD21 Controller performs a self-test procedure when it operates
in either of two modes: the normal mode or the burn-in mode. These
two modes and their corresponding self-test procedures are
described in the following subsections.
6.3.1 NORMAL MODE
The MD21 Controller operates in the normal mode when it performs
typical disk controller functions such as a disk format operation
or a read operation. When the MD21 Controller is operating in the
normal mode and power-up or reset conditions occur, it performs a
self-test procedure to determine whether its interface circuits,
memory, and on-board microprocessor are operative. The self-test
procedure consists of several individual tests that exercise
separate components of the MD21 Controller. These tests are
performed sequentially? the success of one test enables the next
test to be executed. If an individual test fails, the MD21
Controller self-test procedure stops at the location of the
failure.
Before the self-test procedure begins, a Power-up Reset Clear code
is output to the two on-board LEDs to indicate that the MD21
Controller is ready to perform a self-test. If the MD21 Controller
self-test procedure succeeds, a Self-Test Pass code is output to
the on-board LEDs. The LED locations on the MD21 Controller are
shown in Figure 6-1, and LED Test Code descriptions are listed in
Table 6-1.
Controller Initialization and Self-Test Procedures 6-5