Barracuda 7200.8 PATA Product Manual, Rev. F
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4.1.3 Set Features command
This command controls the implementation of var i ous f eatur es th at th e dr ive sup ports. When the drive receives
this command, it sets BSY, checks the contents of the Features register, clears BSY and generates an inter-
rupt. If the value in the register does not represent a feature that the drive supports, the command is aborted.
Power-on default has the read look-ahead and write caching features enabled. The acceptable values for the
Features register are defined as follows:
Note. At power-on, or after a hardware or software reset, the default values of the features are as indi-
cated above.
4.1.4 S.M.A.R.T. commands
S.M.A.R.T. provides near-term failure prediction for disc drives. When S.M.A.R.T. is enabled, the drive moni-
tors predetermined drive attributes that are susceptible to degradation over time. If self-monitoring determines
that a failure is likely, S.M.A.R.T. makes a status report available to the host. Not all failures are predictable.
S.M.A.R.T. predictability is limited to the attributes the drive can monitor. For more information on S.M.A.R.T.
commands and implementation, see the Draft ATA-7 Standard.
SeaTools diagnostic software activates a built-in drive self-test (DST S.M.A.R.T. command for D4H) that elimi-
nates unnecessary drive returns. The diagnostic software ships with all new drives and is also available at:
http://seatools.seagate.com.
02HEnable write cache (default).
03HSet transfer mode (based on value in Sector Count register).
Sector Count register values:
00HSet PIO mode to default (PIO mode 2).
01HSet PIO mode to default and disable IORDY (PIO mode 2).
08HPIO mode 0
09HPIO mode 1
0AHPIO mode 2
0BHPIO mode 3
0CHPIO mode 4 (default)
20HMultiword DMA mode 0
21HMultiword DMA mode 1
22HMultiword DMA mode 2
40HUltra DMA mode 0
41HUltra DMA mode 1
42HUltra DMA mode 2
43HUltra DMA mode 3
44HUltra DMA mode 4
45HUltra DMA mode 5
55HDisable read look-ahead (read cache) feature.
82HDisable write cache.
AAHEnable read look-ahead (read cache) feature (default).
F1HReport full capacity available