How many bytes does an ascii code occupy?

An ASCII code occupies one byte. ASCII code is a coding standard used to represent characters. It uses 7-bit binary numbers to represent 128 different characters, including letters, numbers, punctuation marks and special characters. characters etc. A byte is the basic unit of computer storage unit. It consists of 8 binary bits. Each binary bit can be 0 or 1. One byte can represent 256 different values, so it can represent all characters in the ASCII code.

The operating system for this tutorial: Windows 10 system, DELL G3 computer.

ASCII code (American Standard Code for Information Interchange) is an encoding standard used to represent characters. It uses 7-bit binary numbers to represent 128 different characters, including letters, numbers, punctuation marks and special characters. characters etc. In computers, ASCII codes are usually represented by 8-bit binary numbers, that is, one ASCII code occupies one byte (8 bits) of storage space.

ASCII code characters are represented by 7-bit or 8-bit binary encoding in the computer and are stored in one byte, that is, one ASCII code occupies one byte.

A byte (Byte) is the basic unit of computer storage unit. It consists of 8 binary bits, each binary bit can be 0 or 1. One byte can represent 256 (2^8) different values, so it can represent all characters in the ASCII code.

It should be noted that with the development of computer technology and the demand for internationalization, ASCII codes have gradually been replaced by more universal coding standards such as Unicode. Unicode uses 16 or 32 bits to represent characters and can represent more character sets, including characters and symbols in various languages.

When using Unicode encoding, one character may occupy multiple bytes of storage space. The specific number of bytes occupied depends on the Unicode encoding scheme used, such as UTF-8, UTF-16 or UTF-32, etc. UTF-8 is a common Unicode encoding scheme that uses variable-length encoding. The encoding length of a character can range from 1 to 4 bytes.

To summarize, an ASCII code usually occupies one byte (8 bits) of storage space. However, with the widespread application of Unicode encoding, a character may occupy multiple bytes of storage space. The specific number of bytes occupied depends on the Unicode encoding scheme used.

ASCII code can be divided into standard ASCII code and extended ASCII code.

Standard ASCII code is also called basic ASCII code. It uses 7 binary digits (the remaining 1 binary digit is 0) to represent all uppercase and lowercase letters, numbers 0 to 9, punctuation marks, and in American Special control characters used in English. Among them:

• 0~31 and 127 (33 in total) are control characters or special communication characters (the rest are displayable characters)

  For example, the control character: LF ( Line feed), CR (carriage return), FF (page feed), DEL (delete), BS (backspace), BEL (ring), etc.;

  Special characters for communication: SOH (header), EOT (End of text), ACK (confirmation), etc.;

  ASCII values 8, 9, 10 and 13 are converted into backspace, tab, line feed and carriage return characters respectively. They do not have a specific graphic display, but will have different effects on text display depending on the application.

• 32~126 (95 in total) are characters (32 is a space), of which 48~57 are ten Arabic numerals from 0 to 9.

• 65~90 are 26 uppercase English letters, 97~122 are 26 lowercase English letters, and the rest are some punctuation marks, arithmetic symbols, etc.

Also note that in standard ASCII, its highest bit (b7) is used as a parity bit. The so-called parity check refers to a method used to check whether errors occur during code transmission. It is generally divided into two types: odd check and even check. Odd parity rules: the number of 1's in a byte of the correct code must be an odd number. If it is not an odd number, add 1 to the highest bit b7; even parity rules: the number of 1's in a byte of the correct code must be an even number. , if it is not an even number, add 1 to the highest bit b7.

The last 128 are called extended ASCII codes. Many x86-based systems support the use of extended (or "high") ASCII. Extended ASCII allows the 8th bit of each character to be used to determine an additional 128 special symbol characters, foreign letters, and graphic symbols.

The ASCII code standard table is as follows

##0x03 ##0000 0100 ##EOT (end of transmission) End of transfer ##0000 0101 0000 0110 0000 0111 ##0000 1000 ##0x0A 0000 1011 0000 1100 0000 1101 0000 1110 0000 1111 ##DC1 (device control 1) Device Control 1 ##0001 0010 0001 0011 0001 0100 ##0001 0110 026 22 ##0001 0111 ##25 0x19 EM (end of medium) End of medium ##0x1C FS ( file separator) file separator ##0001 1101 ##0001 1110 0001 1111 ##0010 0000 040 32 0x20 (space) space 0010 0001 041 ##0010 0010 ##0x23 ##044 ##046 38 0x26 & 和 0010 0111 ##0010 1000 051 41 0x29 ) Closing bracket 052 ##053 43 0x2B plus sign 0010 1100 054 44 0x2C , comma ##0010 1101 ##0011 0011 063 51 0x33 ##0100 ##Character 5 0011 0110 0011 0111 071 57 0x39 9 Characters 9 072 58 0x3A : ##0011 1110 076 62 ## Email Symbol 0100 0001 0101 65 0x41 A 0100 0010 ##0100 0011 ##0104 68 0105 ##Capital letter H ##0100 1001 ##01001010 ##Capital letter J 0113 ##uppercase letters K 0100 1100 0114 76 0x4C L 0100 1101 0100 1110 ##0x4E N Capital N 0117 79 0x4F 0120 ##0122 82 0x52 R 0101 0011 ##V uppercase letters V 0101 0111 0127 87 0x57 W 0101 1000 0101 1001 0101 1010 0101 1011 ##0101 1111 0137 95 0x5F ##0110 0000 0110 0001 ##lowercase a 0110 0010 0110 0011 ##0x63 c lower case c 0144 ##0110 0101 0145 ##0x66 f ##lower case g 0110 1000 0150 104 0x68 h lower case h 0110 1001 0151 ##0153 0154 ##lower case m 0110 1110 0156 0110 1111 ##0x70 0111 0001 0161 ##r 0111 0011 0111 0100 ##0x75 0166 0167 ##lower case x 0111 1001 0171 121 0x79 y lower case y ##0111 1010 0111 1011 0111 1100 ##0177 ##Size rules

ASCII table

Bin (binary)	Oct (octal)	Dec (decimal)	Hex (Hex)	Abbreviation/Character	Explanation
0000 0000	00	0	0x00	NUL(null)	null character
0000 0001	01	1	0x01	SOH(start of headline)	Title start
0000 0010	02	2	0x02	STX (start of text )	Start of text
##0000 0011	03	3	##ETX (end of text)	End of text
04	4	##0x04
05	5	0x05	ENQ (enquiry)	Request
06	6	0x06	ACK (acknowledge)	Receive notification
07	7	0x07	BEL (bell)	Bell
010	8	##0x08	BS (backspace)	Backspace	0000 1001
011	9	0x09	HT (horizontal tab)	Horizontal tab
0000 1010	##012	10	##LF (NL line feed, new line)	Line feed key
013	11	0x0B	VT (vertical tab)	vertical tab
014	12	0x0C	FF (NP form feed, new page)	Page key
015	13	0x0D	CR (carriage return)	Enter key
016	14	0x0E	SO (shift out)	No need to switch
017	15	##0x0F	SI ( shift in)	Enable shift
0001 0000	020	16	0x10	DLE (data link escape)	Data link escape
0001 0001	021	17	0x11
022	18	0x12	DC2 (device control 2)	Device control 2
023	19	0x13	DC3 (device control 3)	Device control 3
024	20	0x14	DC4 (device control 4)	Device control 4
##0001 0101	025	21	0x15	NAK (negative acknowledge)	Reject to accept
		##0x16	SYN (synchronous idle)	SYNC IDLE
027	23	0x17	ETB (end of trans. block)	End Transmission Block	##0001 1000
030	24	0x18	CAN (cancel)	Cancel	0001 1001
031
0001 1010	032	26	0x1A	SUB (substitute)	instead of
0001 1011	033	27	##0x1B	ESC (escape)	Escape (overflow)
0001 1100	034	28
035	29	0x1D	GS (group separator)	Group symbol
036	30	0x1E	RS (record separator)	record separator
##037	31	0x1F	##US (unit separator)	Unit separator
	##33	0x21	!	exclamation mark
042	34	##0x22	"	Double quotes	0010 0011
043	35				##0010 0100
36	0x24	$	dollar sign
0010 0101	045	37	0x25	##%	Percent sign
0010 0110
##047	39	0x27	'	Closing single quotation mark
050	40	##0x28	(	Open brackets	##0010 1001
					0010 1010
	42	0x2A	##*	Asterisk
0010 1011
055	45	##0x2D	-	Minus Sign/Dash	##0010 1110
056	46	0x2E	.	Period	0010 1111
057	47	0x2F	/	slash
0011 0000	060	48	0x30	0	Characters 0
0011 0001	061	49	0x31	1	Character 1
0011 0010	062	##50	0x32	2	Character 2
			##3	Character 3
064	## 52	0x34	4	Characters 4	0011 0101
065	53	0x35	##5
##066	54	0x36	6	##Characters 6
067	55	0x37	7	Characters 7	##0011 1000
070	56	0x38	8	Characters 8	##0011 1001
					0011 1010
				Colon
0011 1011	073	59	0x3B	;	Semicolon
0011 1100	074	60	0x3C		is less than
## 0011 1101	075	61	0x3D	=	EQUAL SIGN
		##0x3E	##>	is greater than	##0011 1111
077	63	0x3F	?	Question mark	0100 0000
0100	64	0x40	##@
				##Capital Letter A
0102	66	0x42	B	Capital B
0103	67	0x43	C	Capital C	##0100 0100
	##0x44	D	uppercase D		0100 0101
69	0x45	E	Capital E
0100 0110	0106	70	0x46	F	uppercase letter F
0100 0111	0107	71	0x47	G	Capital G
0100 1000	0110	72	##0x48	H
0111	73	0x49	I	Capital letter I
0112	##74	0x4A	J		0100 1011
	75	0x4B	##K
				##Capital L
0115	##77	0x4D	M	uppercase letter M
0116	##78				0100 1111
		##O	upper case O		0101 0000
80	0x50	P	Capital P
0101 0001	0121	81	0x51	##Q	uppercase letter Q
0101 0010				##Capital letter R
0123	##83	0x53	S	Capital letter S	##0101 0100
0124	84	0x54	T	Capital T	0101 0101
0125	85	0x55	U	uppercase letter U	0101 0110
0126	86	##0x56
				##Capital letter W
0130	##88	0x58	X	Capital letter X
0131	89	0x59	Y	Capital letter Y
0132	90	0x5A	Z	Capital letter Z
0133	##91	0x5B	[	Open square brackets
0101 1100	0134	92	0x5C	##\	Backslash
0101 1101	0135	93	0x5D	]	Closing square bracket
0101 1110	0136	94	0x5E	^	Caret
			##_	Underscore
0140	96	0x60	`	Open single quotation mark
0141	97	0x61	##a
##0142	98	0x62	b	##lower case b
##0143	99				##0110 0100
100	0x64	d	lower case d
##101	0x65	e	lowercase e	0110 0110	0146
102			lower case f
0110 0111	0147	103	0x67	##g
	##105	##0x69	i	lowercase i	##0110 1010
0152	106	0x6A	j	Lower case j	##0110 1011
107	0x6B	k	lower case k		0110 1100
108	0x6C	##l	lower case letters l
0110 1101	0155	109	0x6D	m
	##110	0x6E	n	lowercase n
0157	##111	##0x6F	o	lowercase o	0111 0000
0160	112	##p	##lowercase p
113	0x71	q	lower case q
0111 0010	0162	114	##0x72	##lowercase r
##0163	115	0x73	s	lowercase s
0164	116	0x74	t	lower case t	##0111 0101
0165	117	##u	lowercase u		0111 0110
118	0x76	v	lower case v		0111 0111
119	0x77	##w	lower case letters w
0111 1000	0170	120	0x78	x
0172	122	0x7A	z	lower case z
0173	123	0x7B	##{	Opening brackets
0174	124	0x7C	|	vertical line
0111 1101	0175	125	0x7D	}	Closing curly brace
0111 1110	##0176	126	0x7E	~	tilde
0111 1111	##127	##0x7F	DEL (delete)	Delete

Common ASCII code size rules: numbers Numbers are smaller than letters. For example, "7"

• The number 0 is smaller than the number 9, and increases in sequence from 0 to 9. For example, "3"
• The letter A is smaller than the letter Z, and increases in order from A to Z. For example, "A"
• The uppercase letters of the same letter are 32 smaller than the lowercase letters. Such as "A"
• The ASCII code sizes of several common letters: "A" is 65; "a" is 97; "0" is 48.

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