"FSFA Reading Notes" Ch 2 computer foundatinons (1)

Data Organization1. Binary conversion.　　Write a number in normal writing order (no matter how many binary), where the leftmost column is called the "most effective symbol" and the rightmost column is called the "least significant symbol." (The Right-most column is called The least significant symbol, and the Left-most column is called The most significant symbol.) Binary, decimal and 16 binary conversion table, learn several electric must be familiar with this ~ 2. Data Sizes in storage Multi-byteData, there are "big-endian" and "small-end Method" Two modes, the difference is the placement of the "most effective symbol" and "minimum valid symbol" order. (Computers differ in how they organize multiple-byte values. Some of them use Big-endianOrdering and put the most significant byte of the number in the first storage byte, and others use Little-endianOrdering and put the least significant byte of the number in the first storage byte.) The difference between the two can be seen intuitively from this picture. 3. Character encoding in order to store data (characters) of non-numeric types, we encode characters in various standards, such as ASCII and Unicode

(... to stores letters and sentences. The most common technique are to encode the characters
Using ASCII or Unicode.)

ASCII codes are not affected by the size-end mode because they account for only one byte.

(the endian ordering of a system does not play a role in how the characters is stored because these are separate 1-byte V Alues.)

4. Data structure structure describes the layout (or I understand it as a protocol), the program according to these agreed-upon layout, access to a specific data domain to get the target value. (Computers know the layout of the data because of data structures. A data structure Describes how data is laid out. It works like a template or map. The data structure is broken to Fields , and each field have a size and name, although this information are not saved with the data.)5. The flag bit sometimes needs the information is two value, one bit can be stored, however the smallest storage unit of the computer is a byte, then can combine several bits into one byte, each bit is called a flag bit. (At this time a variety of powerful bit operations can be useful ~) (A more efficient method is-pack several of these binary conditions into one value. Each bit in the value corresponds to a feature or option.)   booting ProcessThe dashed line describes the transfer process of control after the computer is powered on, i.e. the boot code in the Bios->mbr->vbr->os

"FSFA Reading Notes" Ch 2 computer foundatinons (1)