SG_SAT_SET_FEATURES(8)						     SG3_UTILS						    SG_SAT_SET_FEATURES(8)

NAME

       sg_sat_set_features - use ATA SET FEATURES command via a SCSI to ATA Translation (SAT) layer

SYNOPSIS

       sg_sat_set_features [--count=CO] [--ck_cond] [--feature=FEA] [--help] [--lba=LBA] [--len={16|12}] [--verbose] [--version] DEVICE

DESCRIPTION

       This  utility  sends an ATA SET FEATURES command to the DEVICE.	This command is used to change settings of ATA non-packet (i.e. disks) and
       packet devices (e.g. cd/dvd drives). Rather than send the SET FEATURES command directly to the device it is sent via a SCSI transport which
       is  assumed  to	contain  a  SCSI to ATA Translation (SAT) Layer (SATL). The SATL may be in an operating system driver, in host bus adapter
       firmware or in some external enclosure.

       The SAT standard (SAT ANSI INCITS 431-2007, prior draft: sat-r09.pdf at www.t10.org) defines two  SCSI  "ATA  PASS-THROUGH"  commands:  one
       using  a  16 byte "cdb" and the other with a 12 byte cdb. This utility defaults to using the 16 byte cdb variant. SAT-2 is also a standard:
       SAT-2 ANSI INCITS 465-2010 and the draft prior to that is sat2r09.pdf . The SAT-3  project  has	started  and  the  most  recent  draft	is
       sat3r01.pdf .

       The  features can be read using the sg_sat_identify utility which uses either the ATA IDENTIFY DEVICE (for non-packet devices) or the IDEN-
       TIFY PACKET DEVICE (for packet devices) command.

OPTIONS

       Arguments to long options are mandatory for short options as well.

       -c, --count=CO
	      the number CO is placed in the "count" field in the ATA SET FEATURES command. Only some subcommands  (a  term  used  for	the  value
	      placed in the "feature" field) require the count field to be set.  The default value placed in the "count" field is 0.

       -C, --ck_cond
	      sets the CK_COND bit in the ATA PASS-THROUGH SCSI cdb. The default setting is clear (i.e. 0). When set the SATL should yield a sense
	      buffer containing a ATA Result descriptor irrespective of whether the ATA command succeeded or failed. When clear  the  SATL  should
	      only yield a sense buffer containing a ATA Result descriptor if the ATA command failed.

       -f, --feature=FEA
	      the  value  FEA  is  placed in the "feature" field in the ATA SET FEATURES command. The term "subcommand" is sometimes used for this
	      value. The default value placed in the "feature" field is 0 which is reserved and hence should not change anything. Two common exam-
	      ples are 2h to enable the write cache and 82h to disable it.

       -h, --help
	      outputs the usage message summarizing command line options then exits. Ignores DEVICE if given.

       -L, --lba=LBA
	      the  number  LBA	is  placed  in	the "lba" field of the ATA SET FEATURES command. Only some sub-commands (a term used for the value
	      placed in the "feature" field) require the lba field to be set. This value is typically not a "logical block address" as the acronym
	      might  imply.   The  default  value  placed in the "lba" field is 0. The maximum value allowed for LBA is 0xfffffffe (or 0xffffff if
	      --len=12).

       -l, --len={16|12}
	      this is the length of the SCSI cdb used for the ATA PASS-THROUGH commands.  The argument can either be 16 or 12. The default is  16.
	      Some SCSI transports cannot convey SCSI commands longer than 12 bytes.

       -v, --verbose
	      increases the level or verbosity.

       -V, --version
	      print out version string

NOTES

       In  the	2.4  series  of Linux kernels the DEVICE must be a SCSI generic (sg) device. In the 2.6 and 3 series block devices (e.g. disks and
       ATAPI DVDs) can also be specified. For example "sg_inq /dev/sda" will work in the 2.6 series kernels.  From  lk	2.6.6  other  SCSI  "char"
       device  names  may  be  used  as well (e.g. "/dev/st0m"). Prior to lk 2.6.29 USB mass storage limited sense data to 18 bytes which made the
       --ck_cond option yield strange (truncated) results.

EXIT STATUS

       The exit status of sg_sat_set_features is 0 when it is successful. Otherwise see the sg3_utils(8) man page.

AUTHOR

       Written by Douglas Gilbert

REPORTING BUGS

       Report bugs to <dgilbert at interlog dot com>.

COPYRIGHT

       Copyright (C) 2007-2013 Douglas Gilbert
       This software is distributed under a FreeBSD license. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A  PARTICULAR  PUR-
       POSE.

SEE ALSO

       sg_sat_identify(sg3_utils), sg_inq(sg3_utils), sdparm(sdparm), hdparm(hdparm)

sg3_utils-1.37							     June 2013						    SG_SAT_SET_FEATURES(8)