Lucky Star 6VA693A, Руководство пользователя

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VIA693/693A 62
A new HDD accessing method to overcome the 528 MB bottleneck. The number of
cylinders, heads & sectors shown in setup may not be the number physically
contained in the HDD. During HDD accessing, the ide controller will transform the
logical address described by sector, head & cylinder into its own physical address
inside the HDD.
The maximum HDD size supported by LBA mode is 8.4 GB which is obtained by
the following formula:
No. Cylinder (1024)
X No. Head (255)
X No. Sector (63)
X No. Bytes Per Sector (512)
8.4 GB
3. Large Mode
Extended HDD access mode supported by Award® software. Some IDE HDDs
contain more than 1024 cylinder without LBA support (in some cases, user do not
want LBA). The Award® BIOS provides another alternative to support these
kinds of large mode:
Cyls. Head Sector Mode
1120 16 59 NORMAL
560 32 59 LARGE
BIOS tricks DOS (or other OS) that the number of cylinders is less than 1024 by
dividing it by 2. At the same time, the number of heads is multiplied by 2. A
reverse transformation process will be made inside int 12h in order to access the
right HDD address the right HDD address!
4. Maximum HDD Size:
No. Cylinder (1024)