K6610170
Rev.2
Dec 22, 2004
- 86 -
7.5.21. Read Max Address Command [F8h]
Task
File
Registers
7 6 5 4 3 2 1 0
Command F8h
LBA High
XX
LBA Mid
XX
LBA Low
XX
Device/Head
X L X
DRV
X X X X
Sector Count
XX
Features
XX
The READ NATIVE MAX command returns the native maximum 28-bit LBA or cylinders of the device which
is not affect by SET MAX ADDRESS command or SET MAX ADDRESS EXT command. The data returned
in the command block registers is the maximum device size as shown in the following tables.
Task
File
Registers
7 6 5 4 3 2 1 0
LBA High
L = 0: Native Maximum Cylinder bit 15 - 8
L = 1: Native Maximum LBA bit 23 - 16
LBA Mid
L = 0: Native Maximum Cylinder bit 7 - 0
L = 1: Native Maximum LBA bit 15 - 8
LBA Low
L = 0: Native Maximum Sector Number
L = 1: Native Maximum LBA bit 7 - 0
Device/Head
-
L
-
DRV L = 0: Native Max Head
L = 1: Native Max LBA
bit 27 - 24
Sector Count
XX
If the 48-bit Address feature set is supported and the 48-bit native max address is greater than 268,435,455,
the READ NATIVE MAX ADDRESS command returns a maximum 28-bit LBA value of 268,435,454.