How many codes are there in the standard ascii character set?

The standard ascii code character set has a total of 128 codes. The standard ASCII code uses 7 binary bits to represent one character. Since 2 to the 7th power is 128, the standard ASCII code character set has a total of 128 codes; and each code represents a basic symbol, that is, using the ASCII code Can represent up to 128 basic symbols.

The standard ascii code character set has a total of 128 codes.

Because the computer can only directly accept, store and process binary numbers. Numerical information can be represented by binary numbers, while non-numeric information must be represented by binary coding. Coding refers to using a small number of basic symbols to combine according to certain rules to represent a large amount of complex and diverse information. Generally speaking, which words and symbols need to be represented by binary codes depends on which words and symbols we require the computer to "recognize". In order to store text and symbols in the computer, the text and symbols must be converted into binary numbers according to the prescribed encoding. At present, computers generally use the ASCII code (American Standard Code for Information Interchange) specified by the International Organization for Standardization to represent English letters and symbols.

Standard ASCII code, usually also called 7-bit code, consists of 7-bit binary code, the highest bit is 0, its range is expressed as 00000000~01111111 in binary, and 0~127 in decimal, a total of 128 types (2 to the 7th power), each code represents a basic symbol, that is to say, up to 128 basic symbols can be represented using ASCII codes.

The standard ASCII code is composed of a binary code consisting of a group of 3 digits and a group of 4 digits. A group of 3 digits constitutes 7 columns, and a group of 4 digits constitutes 15 rows. The behavior is the lower 4 digits and the column is the upper 3 digits. According to the column and row positions of letters and numbers, an ASCII code can be fixed. For example: the letter A is located in column 4 and row 1, that is, the ASCII code is 01000001BCD. Similarly, given a 7-bit ASCII, a corresponding number, letter or symbol can be immediately found.

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