Fujitsu MAS3735 Computer Drive User Manual


 
Command Specifications
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Table 3.1 MODE SENSE Data Type Specifications
PC Type of Parameter Transferred to the INIT
00 Current Values:
Reports each "Current" parameter value. The "Current" values are either of the following values.
Values specified by a MODE SELECT or MODE SELECT EXTENDED command which is finally
normally terminated.
When a MODE SELECT or MODE SELECT EXTENDED command is not executed after the power is
switched on, after a RESET condition or after a BUS DEVICE RESET message issued by any INIT is
received, the same values as "Save" values. However, if "Save" values do not exist for parameters
other than those on Page 3 and Page 4 (excluding byte 17), the same values as "Default" values.
01 Variable Values:
The INIT reports variable parameter fields and parameter bits through the MODE SELECT or MODE
SELECT EXTENDED command. A "1" is reported in the variable fields and bit positions in each page
descriptor and "0" is reported in the fields and bit positions which cannot be changed. See the description
of each page descriptor for the MODE SELECT command (Section 3.1.5) concerning the variability of
each parameter.
10 Default Values:
Reports the "Default" value of each parameter. See the description of each page descriptor for the MODE
SELECT command (Section 3.1.5) concerning the actual default value of each parameter.
11 Save Values:
Reports the "Save" value of each parameter. The "Save" values are either of the following values.
For parameters other than those on Page 3 and Page 4 (excluding byte 17), these are the values specified
in a MODE SELECT or MODE SELECT EXTENDED command in which the "SP" bit after the final
execution is completed is "1." When a MODE SELECT or MODE SELECT EXTENDED command in
which the "SP" bit is "1" is not executed (when "Save" values do not exist), these are the same values as
the "Default" values.
The values in the parameters in Page 3 and Page 4 (excluding byte 17) are the values save to the disk
media during execution of the FORMAT UNIT command.
The "Transfer Byte Length" field in the CDB specifies the total number of bytes of MODE SENSE
data which can be transferred to the INIT by this command. The IDD transfers the number of bytes
of all the MODE SENSE data specified in the "Page code" field or the portion of MODE SENSE
data with the length specified in the "Transfer Byte Length" field, whichever is smaller. When zero
is specified in the "Transfer Byte Length" field, this command is terminated without anything being
transferred.
Figure 3.10 shows the data configuration in the parameter list (MODE SENSE data) transferred to
the INIT by this command. The parameter list consists of a 4-byte header, an 8-byte block
descriptor and one or more page descriptors, specified in the CDB, which are transferred in order.
However, when "1" is specified in the DBD bit of the CDB, the block descriptor is not transferred.
Also, when X '00' is specified in the "Page code" field of the CDB, the page descriptor is not
transferred.