Chapter 4
SA7
4-6
®
CHS (Normal mode):
Standard normal mode supports hard disks of up to 528 MB or less. This mode directly uses positions
indicated by Cylinders (CYLS), Heads, and Sectors to access data.
®
LBA (Logical Block Addressing) mode:
The earlier LBA mode can support HDD capacities of up to 8.4 GB, and this mode uses a different
method to calculate the position of disk data to be accessed. It translates Cylinders (CYLS), Heads
and Sectors into a logical address where data is located. The Cylinders, Heads, and Sectors displayed
in this menu do not reflect the actual structure of the hard disk, they are just reference values used to
calculate actual positions. Currently, all high capacity hard disks support this mode, that’s why we
recommend you use this mode. Currently, the BIOS can support the INT 13h extension function,
enabling the LBA mode to support hard disk drive capacities exceeding 8.4 GB.
®
Large Mode:
When the number of cylinders (CYLs) of the hard disk exceeds 1024 and DOS is not able to support it,
or if your operating system does not support LBA mode, you should select this mode.
®
Auto:
Just let the BIOS detect your HDD access mode and make the decisions.
Capacity:
This item auto displays your HDD size. Note that this size is usually slightly greater than the size
given by a disk checking program of a formatted disk.
Note
All the items below are available when you set the item
Primary IDE Master
to
Manual
.
Cylinder:
When disks are placed directly above one another along the shaft, the circular vertical "slice"
consisting of all the tracks located in a particular position is called a cylinder. You can set the number
of cylinders for a HDD. The minimum number you can enter is 0, the maximum number you can
enter is 65536.
Head:
This is the tiny electromagnetic coil and metal pole used to create and read back the magnetic patterns
on the disk (also called the read/write head). You can configure the number of read/write heads. The
minimum number you can enter is 0, the maximum number you can enter is 255.
Precomp:
The minimum number you can enter is 0, the maximum number you can enter is 65536.
Warning
Setting a value of 65536 means no hard disk exists.
Landing Zone:
This is a non-data area on the disk's inner cylinder where the heads can rest when the power is turned
off. The minimum number you can enter is 0, the maximum number you can enter is 65536.
