Fujitsu MHW2080BJ 用户手册

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5.4  Command Protocol 
5.4.2  PIO data-in command protocol 
Execution of the following commands involves data transfers from the device to 
the host system: 
• 
IDENTIFY DEVICE 
• 
READ BUFFER 
• 
READ LOG EXT 
An outline of this protocol is as follows: 
3)  When the device is ready to send data, it sets 0 in the BSY bit, 1 in the DRQ 
bit, and 1 in the I bit of the Status field of the PIO Setup FIS, then sends this 
FIS to the host.  At this time, if the requested data is read from the last sector 
to be processed, the device sets 0 in both the BSY bit and DRQ bit of the 
E_Status field.  Otherwise, the device sets 1 in the BSY bit and 0 in the DRQ 
bit of the E_Status field. 
 
• 
READ SECTOR(S) (EXT) 
• 
READ MULTI (EXT) 
• 
SMART READ DATA 
• 
SMATR READ LOG SECTOR 
• 
DEVICE CONFIGRATION IDENTIFY 
Data of one or more sectors is transferred from the device to the host.  
1)  The device receives a PIO data-in command with the RegHD FIS. 
2)  If an error remaining in the device prevents command execution, the device 
sends the RegDH FIS with 1 set in the I bit. 
4)  The device sends the DATA FIS to the host. 
5)  When all data has been transferred, command execution is completed.  If any 
data remains to be transferred, this protocol is repeated starting from step 3).  
(The maximum data size is 8 KB.) 
 
 
C141-E259 
5-177