Set Features Command - Seagate ST1.2 - Series 8 GB Removable Hard Drive Product Manual

4.1.4

Set Features command

This command controls the implementation of various features that the drive supports. 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:
Table 11: Features register values
Feature Description
01 Enable 8-bit data transfer; Only in True IDE mode.
H
02 Enable Write Cache.
H
Used for Set transfer mode Command.
03
H
Sector Count register values:
00 Set PIO mode to default (PIO mode 2).
H
01 Set PIO mode to default and disable IORDY (PIO mode 2).
H
08 PIO mode 0
H
09 PIO mode 1
H
0A PIO mode 2
H
0B PIO mode 3
H
0C PIO mode 4 (default)
H
20 Multiword DMA mode 0
H
21 Multiword DMA mode 1
H
22 Multiword DMA mode 2
H
40 Ultra DMA mode 0
H
41 Ultra DMA mode 1
H
42 Ultra DMA mode 2
H
05 Enable advanced power management
H
0A Enable Power Level 1 commands
H
44 Product Specific ECC bytes (XX bytes) apply on Read/Write Long Command
H
55 Disable read look-ahead (read cache) feature.
H
66 Disable Power On Reset (POR) establishment of defaults at Soft Reset.
H
ST1.2 Series Product Manual, Rev. B
Availability in Interface Mode
CF Memory TrueIDE
or I/O or IDE
No Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
No Yes
No Yes
No Yes
No Yes
No Yes
No Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
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