Point out the arrangement law of characters in ASCII code table.

1, with seven binary codes, can represent 128 characters.

2. The codes of numbers 0 ~ 9 are 30H~39H respectively. English capital letters A, B, C, ..., Z are arranged from 4 1H downwards. The difference between case and case is 32.

3.0000000 ~ 010111are general control characters and special characters.

4. From 20H(32), it is a printable character, and 20H is a space. There are ten numeric characters starting from 30H(48), 40H(64) followed by 4 1H is the capital letter "a" and so on, and 60H(96) followed by 6 1H is the lowercase letter "a" and so on.

Extended data:

It should be pointed out that:

In standard ASCII, its highest bit (b7) is used as parity bit, which refers to a method for checking whether there is an error in code transmission. Generally, it can be divided into odd check and even check.

Odd parity stipulates that the number of 1 in a byte of the correct code must be odd. If it is not an odd number, add 1 to the highest bit b7.

Even parity specifies that the number of 1 in one byte of the correct code must be even. If it is not an even number, the highest bit b7 plus 1 [1]? .

128 code is called extended ASCII code, and many x86-based systems support the use of extended (or "high") ASCII codes.

Baidu encyclopedia -ASCII code