Fujitsu MHV2040BH User Manual

C141-E224 

5-157 

Native Queued commands include the following commands: 

READ FP DMA QUEUED 

WRITE FP DMA QUEUED 

An outline of the command queuing protocol is as follows: 

1)  After the device receives a Native Queued command, if the command is 

executable, the device sends to the host the RegDH FIS with the settings of I 
bit = 0, BSY bit = 0, and DRQ bit = 0, and it places the command in the 
command queue.  Otherwise, the device sends the RegDH FIS to the host to 
report an error. 

2)  If the device receives a command that is not a Native Queued command 

during command queuing, the device sends to the host the RegDH FIS with 
the settings of ERR bit = 1, I bit = 1, BSY bit = 0, DRQ bit = 0, and Error 
register = 0x04 to report an abort. 

3)  When the device is ready to send data for the data transfer of the READ FP 

DMA QUEUED command, it sends to the host the DMA Setup FIS with the 
settings of TAG = #, D bit = 1, I bit = 0, and A bit = 0, and it then sends the 
Data FIS to the host.  (The Data FIS is transferred in units of up to 8 KB). 

4)  When the read data transfer requested by the command is completed and the 

command is completed normally, the bit in the SActive field in the SetDB 
FIS corresponding to the tag number of the completed command is set by the 
device, and the device sets 0 in the Err bit and 0 in the Error register in the 
Set Device Bits FIS.  Then, it sends the Set Device Bits FIS to the host. 

5)  For the data transfer of the WRITE FP DMA QUEUED command, if the 

DMA Setup Auto Activate function is disabled, the device sends to the host 
the DMA Setup FIS with the settings of TAG = #, D bit = 0, A bit = 0, and I 
bit = 0, and it sends the DMA Active FIS before it receives the Data FIS from 
the host.  (The Data FIS is transferred in units of up to 8 KB, with the actual 
length of the Data FIS varying depending on the host). 

6)  If the DMA Setup AutoActivate function is enabled, the device sends to the 

host the DMA Setup FIS with the settings of TAG = #, D bit = 0, A bit = 1, 
and I bit = 0, and it then receives the Data FIS from the host (in units of 8 
KB, 16 sectors). 

7)  When the write data transfer requested by the command is completed and the 

command is completed normally, the bit in the SActive field in the SetDB 
FIS corresponding to the tag number of the completed command is set by the 
device, and the device sets 0 in the Err bit and 0 in the Error register in the 
Set Device Bits FIS.  Then, it sends the Set Device Bits FIS to the host.  (The 
DMA Setup AutoActivate function can be enabled and disabled by the SET 
FEATURES command.  The function is disabled by default.)