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SEAGATE 1200 SSD PRODUCT MANUAL, REV. A 58
ST100FM0023 53 54 31 30 30 46 4D 30 30 32 33
ST100FM0033 53 54 31 30 30 46 4D 30 30 33 33
ST100FM0043 53 54 31 30 30 46 4D 30 30 34 33
ST100FM0053 53 54 31 30 30 46 4D 30 30 35 33
ST100FM0063 53 54 31 30 30 46 4D 30 30 36 33
ST100FM0073 53 54 31 30 30 46 4D 30 30 37 33
ST100FM0083 53 54 31 30 30 46 4D 30 30 38 33
ST100FM0093 53 54 31 30 30 46 4D 30 30 39 33
ST100FM0103 53 54 31 30 30 46 4D 30 31 30 33
ST100FM0113 53 54 31 30 30 46 4D 30 31 31 33
ST100FM0123 53 54 31 30 30 46 4D 30 31 32 33
11.3.2 MODE SENSE data
The MODE SENSE command provides a way for the drive to report its operating parameters to the initiator. The drive
maintains four sets of mode parameters:
1. Default values
Default values are hard-coded in the drive firmware stored in flash E-PROM (nonvolatile memory) on the drive’s PCB.
These default values can be changed only by downloading a complete set of new firmware into the flash E-PROM. An
initiator can request and receive from the drive a list of default values and use those in a MODE SELECT command to
set up new current and saved values, where the values are changeable.
2. Saved values
Saved values are stored on the drive’s media using a MODE SELECT command. Only parameter values that are
allowed to be changed can be changed by this method. Parameters in the saved values list that are not changeable by
the MODE SELECT command get their values from default values storage.
When power is applied to the drive, it takes saved values from the media and stores them as current values in volatile
memory. It is not possible to change the current values (or the saved values) with a MODE SELECT command before
the drive is “ready.” An attempt to do so results in a “Check Condition” status.
On drives requiring unique saved values, the required unique saved values are stored into the saved values storage
location on the media prior to shipping the drive. Some drives may have unique firmware with unique default values also.
On standard OEM drives, the saved values are taken from the default values list and stored into the saved values stor-
age location on the media prior to shipping.
3. Current values
Current values are volatile values being used by the drive to control its operation. A MODE SELECT command can be
used to change the values identified as changeable values. Originally, current values are installed from saved or default
values after a power on reset, hard reset, or Bus Device Reset message.
4. Changeable values
Changeable values form a bit mask, stored in nonvolatile memory, that dictates which of the current values and saved
values can be changed by a MODE SELECT command. A one (1) indicates the value can be changed. A zero (0) indi-
cates the value is not changeable. For example, in Table 18, refer to Mode page 81, in the row entitled “CHG.” These are
hex numbers representing the changeable values for Mode page 81. Note in columns 5 and 6 (bytes 04 and 05), there is
00h which indicates that in bytes 04 and 05 none of the bits are changeable. Note also that bytes 06, 07, 09, 10, and 11
are not changeable, because those fields are all zeros. In byte 02, hex value FF equates to the binary pattern 11111111.
If there is a zero in any bit position in the field, it means that bit is not changeable. Since all of the bits in byte 02 are
ones, all of these bits are changeable.
The changeable values list can only be changed by downloading new firmware.
Note. Because there are often several different versions of drive control firmware in the total population of drives in the
field, the MODE SENSE values given in the following tables may not exactly match those of some drives.
The following tables list the values of the data bytes returned by the drive in response to the MODE SENSE command pages
for SCSI implementation (see the SAS Interface Manual ).
DEF = Default value. Standard OEM drives are shipped configured this way.
CHG = Changeable bits; indicates if default value is changeable.