Amount Of Storage Available On A Diskette - IBM 5110 User Manual

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AMOUNT OF STORAGE AVAILABLE ON A DISKETTE
The amount of storage available on a diskette depends upon:
• Whether data can be recorded on just one side or on both sides of
the diskette
• The number of sectors per cylinder
.' The number of bytes per sector
Each diskette has 77 cylinders. Cylinder 0 is the index track and is
reserved for information (file headers) about the diskette files.
Cylinders 75 and 76 are alternate cylinders that are used as
replacements for bad cylinders. This leaves cylinders 1 through 74
available for data storage. The following chart shows the amount of
storage available with the different types of diskettes:
Sectors Bytes
Available
per per Storage in Bytes
Cylinder
Sector
(cylinders 1-74)
26 128 246,272
Diskette 1
15 256 284,160
8 512 303,104
52 128
492,544
Diskette 2 30 256
568,320
16 512 606,208
52 256 986,088
Diskette 2D
30 512 1,136,640
16 1,024 1,212,416
Although the previous chart shows the maximum amount of diskette
storage, the amount of diskette storage actually available to you
depends on:
II
The number of files and the size of the files marked on the diskette
I'
The types of data files that are written to the diskette
• The allocation of file space as the result of previous )MARK and
)FREE commands