Fujitsu M2488, Руководство по эксплуатации продукта

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MEDIA CHANGER COMMANDS M2488 PRODUCT GUIDE
6-8 CG00000-011503 REV. A March 1997
6-2.2.2 MODE SELECT CHECK CONDITION Status
For the following conditions, a MODE SELECT command will fail with a CHECK CONDITION
status with the sense key set to ILLEGAL REQUEST, and the additional sense code set to
INVALID FIELD IN PARAMETER LIST. The requested mode settings/changes, will not be per-
formed.
(a) If the initiator attempts to change any field that is not changeable as reported by the target.
(b) If the initiator sends a value for a parameter that is outside the range supported by the target
and rounding is not permitted for that parameter.
(c) If the initiator sets any field in the mode parameter header or block descriptor to an unsup-
ported value.
(d) If the initiator sends a mode page with a page length not equal to the page length returned by
the MODE SENSE command for that page.
(e) If the initiator sets any reserved field in the mode parameter list to a non-zero value.
Certain parameters sent to a target with the MODE SELECT command contain a range of values.
The target rejects unsupported values unless rounding is permitted in the description of the param-
eter. If rounding is permitted, then when the target receives a value not supported, it rounds the
value received to a supported value.
Rounding of MODE SELECT parameter values, when permitted, is performed as follows: A tar-
get that receives a MODE SELECT parameter value that is not an exact supported value, adjusts
the value to one that it supports, and returns CHECK CONDITION status with a sense key of
RECOVERED ERROR. The additional sense code is set to ROUNDED PARAMETER. The initi-
ator is responsible to issue a MODE SENSE command to learn what value the target has rounded.
A parameter list length that results in the truncation of any header or mode page causes the target
to terminate the command with a CHECK CONDITION status, with a sense key of ILLEGAL
REQUEST, and the additional sense code set to PARAMETER LIST LENGTH ERROR.
6-2.2.3 MODE SELECT Data
The MODE SELECT data to be sent by the initiator should be in the form of a four-byte header,
followed by zero or more variable length pages. The following table illustrates the format of the
MODE SELECT parameter list:
Table 6-5. MODE SELECT Parameter List Format
BITS
BYTES 7 6 5 4 3 2 1 0
0 - 3 Mode Parameter Header (4 bytes)
4 - N Pages