Fujitsu MHV2120BH User Manual

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Interface 
 
5-150 
C141-E224 
5.4   Command Protocol 
The host should confirm that the BSY bit of the Shadow Block Status register of 
the device is 0 prior to issue a command. If BSY bit is 1, the host should wait for 
issuing a command until BSY bit is cleared to 0. 
Commands can be executed only when the DRDY bit of the Status register is 1.  
However, the following commands can be executed even if DRDY bit is 0. 
• 
EXECUTE DEVICE DIAGNOSTIC 
• 
INITIALIZE DEVICE PARAMETERS 
Note:  Each FIS type is referred to as follows in this section. 
FIS (Frame Information Structure) type 
Abbreviation 
Register - Host to Device 
RegHD 
Register - Device to Host 
RegDH 
DMA Active - Device to Host 
DMA Active 
DMA Setup - Device to Host or Host to Device 
(Bidirectional) 
DMA Setup 
Set Device Bits - Device to Host 
SetDB 
BIST Active - Bidirectional 
BIST Active 
PIO Setup - Device to Host 
PIO Setup 
Data - Host to Device or Device to Host (Bidirectional)  DATA 
 
5.4.1  Non-data command protocol 
Execution of the following commands does not involve data transfer between the 
host and the device. 
• 
RECALIBRATE 
• 
SEEK 
• 
READ VERIFY SECTOR(S) (EXT) 
• 
EXECUTE DEVICE DIAGNOSTIC 
• 
INITIALIZE DEVICE PARAMETERS 
• 
SET FEATURES 
• 
SET MULTIPLE MODE 
• 
SET MAX ADDRESS (EXT)