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7K200 SATA OEM Specification 
70/173 
12.17  SMART Command Transport (SCT) 
SMART Command Transport (SCT) feature set is supported.  The SMART Read Log and SMART 
Write Log commands or Read Log Ext and Write Log Ext commands are used to issue a command in 
this feature sets.   Log page E0h is used to issue commands and return status.  Log page E1h is 
used to transport data.  Please refer to the section 8 SCT Command Transport in ATA8-ACS 
specification for more detail. 
The following Action codes are supported. 
Action 
code 
Description 
0002h Write 
Same 
command 
0003h 
Error Recovery Control command 
Feature Control command 
Feature code 
0001h 
Write Cache 
0004h 
Feature code 
0003h 
Time Interval for temperature logging 
0005h 
SCT Data Table command 
Table 39 SCT Action Code Supported   
13   Command Protocol   
The commands are grouped into different classes according to the protocols followed for command 
execution. The command classes with their associated protocols are defined below.   
Please refer to Serial ATA Revision 2.6 (Section 11. device command layer protocol) about each 
protocol. 
For all commands, the host must first check if BSY=1, and should proceed no further unless and 
until BSY=0. For all commands, the host must also wait for RDY=1 before proceeding.   
A device must maintain either BSY=1 or DRQ=1 at all times until the command is completed. The 
INTRQ signal is used by the device to signal most, but not all, times when the BSY bit is changed 
from 1 to 0 during command execution.   
A command shall only be interrupted with a COMRESET or software reset. The result of writing to 
the Command register while BSY=1 or DRQ=1 is unpredictable and may result in data corruption. A 
command should only be interrupted by a reset at times when the host thinks there may be a 
problem, such as a device that is no longer responding.   
Interrupts are cleared when the host reads the Status Register, issues a reset, or writes to the 
Command Register.   
“Table 138 Timeout Values” on Page 171 shows the device timeout values.