Data recovery base – 5. HDD mystery addressing mode
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1.1.6 Addressing Modes
The so-called addressing modes, to be a metaphor, when we want to find a specific word from a book, we need to know what the word is stored in the location, which is its "address." So in what way to locate the position of the word it?
 One method is to use the number of pages, the number of rows and columns to position it. Just know that this word is located in the first few pages, the first few lines, the first few columns, you can find the word. This goal is to find a kind of "addressing." We can also carry out all the words in the book from front to back number, just know one word of numbers will be able to find it, this is a way of addressing.Similarly, when you want to access the data on the disk, but also need to use some addressing ways to find it. Addressing the hard disk is divided into two types:
C / H / S addressing.LBA addressing mode.
1. C / H / S addressing
C / H / S addressing mode is a way of addressing used in the past. It is to use cylinder (Cylinder) / head (Head) / Sector (Sector) three parameters to locate a unique sector address.
 2. LBA addressing mode
LBA addressing mode that Logic Block Address (LBA), also known as "linear addressing mode." Because the C / H / S addressing modes existing capacity constraints have been unable to meet the growing data storage requirements, so the introduction of the LBA addressing mode. In this mode, there is no longer a three-dimensional definition of the disk cylinder, head, sector, but all the sectors on the disk in order from "0" to number, until the maximum number of sectors of the disk minus 1, As shown in Figure 1.7.
 Figure 1.7 LBA addressing mode
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