1.1.3.1 Hard Disk Geometry & Internals

  • Hard disk has one or more rotating plates. They are stacked on  one on another. (Remember CD or DVD holder)
  • Every plate is coated (sometime both sides) by magnetic material.
  • Every plate is divided in number of circles called as track.
  • For every coated surface of plate, there is a head to perform read and write operations.
  • Track is divided in multiple sectors .It is the smallest addressable unit is known as a sector. 
  • In computer , numbering starts from 0. means if total no of objects are n then they are numbered from 0 to (n-1)

##Do not forget
Sector->track->plate or cylinder

## CHS Addressing
Room no 108 means 1st floor and 8th room. CHS is using similar method CHS (Cylinder, Head, Sector)
Address - Explanation 
0,0,0    0th Cylinder - 0th track - 0th sector || in computer everything starts with 0
1,0,0    1st Cylinder - 0th track - 0th sector
at

2.3.2 Essential & Non-essential data

  • 1.1.3.3 Types of Sector Addresses
    Physical address is address of the sector with respect to start of physical media. One way of addressing was to mentioning plate number , tr...
  • 1.1.2.1 CPU & Machine Codes
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  • 1.1.1.3 Strings and Encoding
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