Pentium SQ578, User Manual

Page: 34 / 57

SQ578
4-6
Write
Precompensation
The actual physical size of a sector gets progressively
smaller as the track diameter diminishes. Yet each
sector must still hold 512 bytes. Write precompensation
circuitry on the hard disk compensates for the physical
difference in sector size by boosting the write current
for sectors on inner tracks. This parameter is the track
number on the disk surface where write
precompensation begins.
Landing Zone This number is the cylinder location where the heads
normally park when the system is shut down.
Sectors The number of sectors per track. MFM drives have 17
sectors per track. RLL drives have 26 sectors per track.
ESDI drives have 34 sectors per track. SCSI and IDE
drives have even more sectors per track.
Capacity The formatted capacity of the drive is the number of
heads times the number of cylinders times the number
of sectors per track times 512 (bytes per sector).
Hard Disk Drive Types
Type Cylinders Heads Write
Precompensation
Landing
Zone
Sectors Capacity
1 306 4 128 305 17 10 MB
2 615 4 300 615 17 20 MB
3 615 6 300 615 17 31 MB
4 940 8 512 940 17 62 MB
5 940 6 512 940 17 47 MB
6 615 4 65535 615 17 20 MB
7 462 8 256 511 17 31 MB
8 733 5 65535 733 17 30 MB
9 900 15 65535 901 17 112 MB
10 820 3 65535 820 17 20 MB
11 855 5 65535 855 17 35 MB
12 855 7 65535 855 17 50 MB
13 306 8 128 319 17 20 MB
14 733 7 65535 733 17 43 MB
16 612 4 0 663 17 20 MB
17 977 5 300 977 17 41 MB
18 977 7 65535 977 17 57 MB
19 1024 7 512 1023 17 60 MB
20 733 5 300 732 17 30 MB
21 733 7 300 732 17 43 MB
22 733 5 300 733 17 30 MB
23 306 4 0 336 17 10 MB
24 925 7 0 925 17 54 MB
25 925 9 65535 925 17 69 MB
26 754 7 754 754 17 44 MB
27 754 11 65535 754 17 69 MB
28 699 7 256 699 17 41 MB
29 823 10 65535 823 17 68 MB
30 918 7 918 918 17 53 MB