Quantum FIREBALL PLUS AS 10.2 User Manual

ATA Bus Interface and ATA Commands
Quantum Fireball Plus AS 10.2/20.5/30.0/40.0/60.0 GB AT 6-71
6.7.25
6.7.256.7.25
6.7.25 Set Features EFh
Set Features EFhSet Features EFh
Set Features EFh
The SET FEATURES command is used by the host to establish certain parameters
which control execution of the following drive features:
• 02h – Enable write cache feature
• 03h – Set transfer mode based on value in Sector Count Register
• 42h – Enable QDT mode
• 55h – Disable read look-ahead feature
• 66h – Disable reverting to power on defaults
• 82h – Disable write cache feature
• AAh – Enable read look-ahead feature
•C2h – Disable QDT mode
• CCh – Enable reverting to power on defaults
At power-on, or after a reset accomplished by either the hardware or software, the
default mode is 4 bytes of ECC, read look-ahead, and write cache enabled.
A host can choose the transfer mechanism by Set Transfer Mode and specifying a
value in the Sector Count register. The upper 5 bits define the type of transfer and
the low order 3 bits encode the mode value.
6.7.26
6.7.266.7.26
6.7.26 Set Features (Ultra ATA/100)
Set Features (Ultra ATA/100)Set Features (Ultra ATA/100)
Set Features (Ultra ATA/100)
Set Transfer Mode
Set Transfer ModeSet Transfer Mode
Set Transfer Mode
A host can choose the transfer mechanism by the Set Transfer mode, subcommand
code 03h, and by specifying a value in the Sector Count register. The upper 5 bits
define the type of transfer and the low order 3 bits encode the mode value.
Table 6-25
Table 6-25 Table 6-25
Table 6-25
Transfer/Mode Values
PIO Default Transfer Mode 00000 000
PIO Default Transfer Mode, Disable IORDY 00000 001
PIO Flow Control Transfer Mode x 00001 nnn
Multiword DMA Mode x 00100 nnn
Ultra DMA Mode 01000 nnn
Reserved 10000 nnn
Key:
nnn = a valid mode number in binary
x = a mode number in decimal for the associated transfer type

Quantum FIREBALL PLUS AS 10.2 Specifications

General

Brand	Quantum
Model	FIREBALL PLUS AS 10.2
Category	Storage
Language	English