Fujitsu MHV2080AS SET Features X’EF’, Features register values and settable modes, ’Bb’, ’Cc’

5.3 Host Commands

(28) SET FEATURES (X’EF’)

The host system issues the SET FEATURES command to set parameters in the Features register for the purpose of changing the device features to be executed.

Upon receipt of this command, the device sets the BSY bit of the Status register and saves the parameters in the Features register. Then, the device clears the BSY bit, and generates an interrupt.

If the value in the Features register is not supported or it is invalid, the device posts an ABORTED COMMAND error.

Table 5.23 lists the available values and operational modes that may be set in the Features register.

Table 5.23 Features register values and settable modes

Features		Drive operation mode
Register
X’02’	Enables the write cache function.
X’03’	Set the data transfer mode.	*1
X’05’	Enables the advanced power management function. *2
X’42’	Enables the Acoustic management function. *3
X’55’	Disables read cache function.
X’66’	Disables the reverting to power-on default settings after software reset.		(*1)
X’82’	Disables the write cache function.
X’85’	Set the advanced power management mode to Mode-0.
X’AA’	Enables the read cache function.
X’BB’	Specifies the transfer of 4-byte ECC for READ LONG and WRITE LONG
	commands.		(*1)
X’C2’	Disables the Acoustic management function.
X’CC’	Enables the reverting to power-on default settings after software reset.		(*1)
*1 Although there is a response to the command, nothing is done.
	At power-on or after hardware reset, the default mode is set as follows.
	Write cache function	: Enabled
	Transfer mode	: PIO Mode-4, Multiword DMA Mode-2
	Advanced power
	management function	: Enabled (Mode-1)
	Acoustic
	management function	: State keeping
	Read cache function	: Enabled

C141-E221 5-89