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12.75 Write Stream DMA Ext (3Ah)
The Write Stream DMA Ext command allows the host to write data using the DMA data transfer protocol. This
command allows for the host to specify to the device that additional actions need to be performed prior to the
completion of the command if the required bits are set.
If the Write Continuous bit is set to one, the device shall not stop execution of the command due to errors. If the WC
bit is set to one and errors occur in the transfer or writing of the data, the device shall continue to transfer the amount
of data requested and then provide ending status with the BSY bit cleared to zero, the SE bit set to one, the ERR bit
cleared to zero, and the type of error, ICRC, IDNF, or ABRT, reported in the error log. If the WC bit is set to one and
the Command Completion Time Limit expires, the device shall stop execution of the command and provide ending
status with BSY bit cleared to zero, the SE bit set to one, the ERR bit cleared to zero, and report the fact that the
Command Completion Time Limit expired by setting the CCTO bit in the error log to one, In all cases, the device shall
attempt to transfer the amount of data requested within the Command Completion Time Limit event if some data
transferred is in error.
Table 264 Write Stream DMA Ext Command (3Ah)
Command Block Output Registers
Command Block Input Registers
Register
7
6
5
4
3
2
1
0
Register
7
6
5
4
3
2
1
0
Data Low
-
-
-
-
-
-
-
-
Data Low
-
-
-
-
-
-
-
-
Data High
-
-
-
-
-
-
-
-
Data High
-
-
-
-
-
-
-
-
Feature
Current
V
V
V
V
-
V
V
V
Error
...See Below...
Previous
V
V
V
V
V
V V
V
Sector Count
Current
V
V
V
V
V V
V
V
Sector
Count
HOB=0
-
-
-
-
-
-
-
-
Previous
V
V
V
V
V
V V
V
HOB=1 -
-
-
-
-
-
-
-
Sector Number Current
V
V
V
V
V V
V
V
Sector
Number
HOB=0
V
V
V
V V
V
V
V
Previous
V
V
V
V
V
V V
V
HOB=1 V
V
V
V
V
V V
V
Cylinder Low
Current
V
V
V
V
V V
V
V
Cylinder
Low
HOB=0
V
V
V
V V
V
V
V
Previous
V
V
V
V
V
V V
V
HOB=1 V
V
V
V
V
V V
V
Cylinder High
Current
V
V
V
V
V V
V
V
Cylinder
High
HOB=0
V
V
V
V V
V
V
V
Previous
V
V
V
V
V
V V
V
HOB=1 V
V
V
V
V
V V
V
Device/Head
1
1
1
D -
-
-
-
Device/Head
-
-
-
-
-
-
-
-
Command
0
0
1
1
1
0
1
0
Status
...See Below...
Error Register
Status Register
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
CRC
UNC 0
IDN
0
ABT
T0N
CCTO BSY RDY SE
DWE DRQ COR IDX
ERR
V
0
0
V
0
V
0
V
0
V
V
0
-
0
-
V
344
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