Fujitsu MBA3147NC User Manual

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5.6.4 Setting 
parameters 
 
The user can specify the optimal operation mode for the user system environments by setting the 
following parameters with the MODE SELECT or MODE SELECT EXTENDED command: 
•  Error recovery parameter 
•  Disconnection/reconnection parameter 
•  Caching parameter 
•  Control mode parameter 
 
With the MODE SELECT or MODE SELECT EXTENDED command, specify 1 for the "SP" bit 
on CDB to save the specified parameter value on the disk.  This enables the HDD to operate by 
using the parameter value set by the user when power is turned on again.  When the system has 
more than one initiator, different parameter value can be set for each initiator. 
 
When the parameters are not set or saved with the MODE SELECT or MODE SELECT 
EXTENDED command, the HDD sets the default values for parameters and operates when power 
is turned on or after reset.  Although the HDD operations are assured with the default values, the 
operations are not always optimal for the system.  To obtain the best performance, set the 
parameters in consideration of the system requirements specific to the user. 
 
This section outlines the parameter setting procedures.  Refer to Subsection 3.1.5 "MODE 
SELECT (15) " and 3.1.6 "MODE SELECT EXTENDED (55)"of the SCSI Logical Interface 
Specifications for further details of the MODE SELECT and MODE SELECT EXTENDED 
commands and specifying the parameters. 
IMPORTANT 
1.  At factory shipment of the HDD, the saving operation for the MODE 
SELECT parameter is not executed.  So, if the user does not set 
parameters, the HDD operates according to the default value of each 
parameter 
 
2.  The MODE SELECT parameter is not saved for each SCSI ID of but as 
the common parameter for all IDs.  In the multi-initiator system, 
parameter setting cannot be changed for each initiator. 
 
3.  Once parameters are saved, the saved value is effective as long as next 
saving operation is executed from the initiator.  For example, even if the 
initialization of the disk is performed by the FORMAT UNIT command, 
the saved value of parameters described in this section is not affected. 
 
4.  When the HDD, to which the saving operation has been executed on a 
system, is connected to another system, the user must pay attention to 
that the HDD operates according to the saved parameter value if the 
saving operation is not executed at installation. 
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