Fujitsu MHT2040BH Benutzerhandbuch

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5.4   Command Protocol 
C141-E203-01EN 5-145 
An outline of this protocol is as follows: 
1)  The device receives a PIO data-out command with the Register HD FIS. 
2)  If an error remaining in the device prevents command execution, the device 
sends the Register DH FIS with 1 set in the I bit. 
3)  When the device is ready to receive data, it sets 0 in the BSY bit and 1 in the 
DRQ bit of the Status field of the PIO Setup FIS.  At this time, the device sets 
0 in the I bit of the Status field of the PIO Setup FIS for a data transfer to the 
first sector, while it sets 1 in the I bit for a data transfer to any sector other 
than the first sector.  Then, it sends this FIS to the host.  In the E_Status field, 
the device sets 1 in the BSY bit and 0 in the DRQ bit. 
4)  The device receives the DATA FIS from the host. 
5)  When all data has been transferred, the device sends the Register DH FIS 
(with 1 set in the I bit) to complete execution of the command.  If the device 
has an error, it reports the error.  If any data remains to be received by the 
device, this protocol is repeated starting from step 3).  (The maximum data 
size is 8 KB.) 
 
 
 
 
Device 
 
 
 
Host 
RegHD 
PIOSU 
DATA 
RegDH 
 
Figure 5.12  PIO data-out command protocol