Code 39

Code 39 example with dollar mark

The coding Code 39 , also briefly 3 of 9 ( "nine three" ), is a discrete bar code symbology with variable length. It provides an alphanumeric character set . In addition to digits and capital letters, seven special characters are defined. Start and stop characters are identical and are represented by the special character "*". Code 39 was developed by Intermec (USA) in 1973 and is specified in ISO / IEC 16388.

construction

Code 39 character set

A barcode consisting of five bars and four spaces is assigned to each character of the available alphabet. There are two different bar and gap widths. The designation Code 39 or "3 of 9" goes back to the structure of the coding. The coded characters are each represented by a total of 9 alternating black and white bars. Three of these bars are wide, all others are narrow. A character therefore consists of 5 black and 4 white bars. This structure enables 44 different characters to be displayed, 40 of which have two wide black bars and one wide white bar. 39 of these 40 options correspond to the digits 0–9, the alphabet (A – Z), the period, the minus sign (or hyphen) and the space. The 40th possibility encodes the start / stop character "*". The last 4 characters (checksum value 39–42) are shown with three wide white bars.

Code 39 is a discrete code with a variable code length (variable number of characters). The code structure allows the bi-directional scanning of the self-checking elements.

For applications with increased requirements for reading security, there is an optional checksum procedure based on a table of values ​​for each character. The “0” character has the numerical value 0, the “1” character has the value 1, the “A” character has the value 10, and the “Z” character has the value 35. “%” is assigned the value 42 as the last character . The value of the test mark is calculated as follows:

${\displaystyle Wert(P)=(Wert(z1)+Wert(z2)+...+Wert(zn))\mod 43}$

For example, the test character of the character string “12345ABCDE /” is the “T”. The "T" comes from the following calculation:

${\displaystyle 1+2+3+4+5+10+11+12+13+14+40=115}$

${\displaystyle 115\mod 43=29}$

${\displaystyle 29\Rightarrow T}$

Code 39 is easy to produce because one character in plain text corresponds to one character in a barcode. Code 39 dominated earlier applications that required alphanumeric coding. Due to the relatively low information density and a small selection of character sets in comparison to other encodings, however, it has recently been increasingly replaced by Code128 . However, due to the restriction to two clearly distinguishable widths, it can be read reliably even with poor print quality; if necessary even with the naked eye.

Character encoding

character	code	meaning	Checksum value
,1'	▮ | || ▮	1	1
'2'	| ▮ || ▮	2	2
'3'	▮▮ |||	3	3
'4'	|| ▮ | ▮	4th	4th
'5'	▮ | ▮ ||	5	5
'6'	| ▮ ▮ ||	6th	6th
'7'	|| | ▮▮	7th	7th
,8th'	▮ | | ▮ |	8th	8th
'9'	| ▮ | ▮ |	9	9
'0'	|| ▮▮ |	0	0
'A'	▮ || | ▮	A.	10
'B'	| ▮ | | ▮	B.	11
'C'	▮▮ | ||	C.	12
'D'	|| ▮ | ▮	D.	13
'E'	▮ | ▮ ||	E.	14th
'F'	| ▮▮ ||	F.	15th
,G'	||| ▮▮	G	16
,H'	▮ || ▮ |	H	17th
'I'	| ▮ | ▮ |	I.	18th
'J'	|| ▮ ▮ |	J	19th
'K'	▮ ||| ▮	K	20th
'L'	| ▮ || ▮	L.	21st
'M'	▮▮ || |	M.	22nd
'N'	|| ▮ | ▮	N	23
,O'	▮ | ▮ | |	O	24
'P'	| ▮▮ | |	P	25th
'Q'	||| ▮ ▮	Q	26th
'R'	▮ || ▮ |	R.	27
'S'	| ▮ | ▮ |	S.	28
'T'	|| ▮▮ |	T	29
'U'	▮ ||| ▮	U	30th
'V'	| ▮ || ▮	V	31
'W'	▮ ▮ |||	W.	32
'X'	| | ▮ | ▮	X	33
'Y'	▮ | ▮ ||	Y	34
'Z'	| ▮▮ ||	Z	35
'-'	| || ▮▮	Hyphen, minus	36
'.'	▮ || ▮ |	Point	37
''	| ▮ | ▮ |	Space, space	38
'*'	| | ▮▮ |	Start, stop
'$'	| | | ||	dollar	39
'/'	| | || |	slash	40
'+'	| || | |	plus	41
'%'	|| | | |	percent	42

Full ASCII Code 39

Code 39 is limited to 43 characters. In order to be able to display all 128 ASCII characters, the system has been expanded as follows: The symbols 0–9, A – Z, “.” And “-” are the same as for Code 39. Lower case letters, other characters and control characters are replaced by two successive symbols formed by Code 39.

Symbol table Full ASCII Code 39

No character Coding 0 NUL % U 1 SOH $ A 2 STX $ B 3 ETX $ C 4th EOT $ D 5 ENQ $ E 6th ACK $ F 7th BEL $ G 8th BS $ H 9 HT $ I 10 LF $ J 11 VT $ K 12 FF $ L 13 CR $ M 14th SO $ N 15th SI $ O 16 DLE $ P 17th DC1 $ Q 18th DC2 $ R 19th DC3 $ S 20th DC4 $ T 21st NAK $ U 22nd SYN $ V 23 ETB $ W 24 CAN $ X 25th EM $ Y 26th SUB $ Z 27 ESC % A 28 FS % B 29 GS % C 30th RS % D 31 US % E

No character Coding 32 [space] [space] 33 ! / A 34 " / B 35 # / C 36 $ / D 37 % / E 38 & / F 39 ' /G 40 ( /H 41 ) / I 42 * / J 43 + / K 44 , / L 45 - - 46 . . 47 / /O 48 0 0 49 1 1 50 2 2 51 3 3 52 4th 4th 53 5 5 54 6th 6th 55 7th 7th 56 8th 8th 57 9 9 58 : / Z 59 ; % F 60 < %G 61 = %H 62 > % I 63 ? % J

No character Coding 64 @ % V 65 A. A. 66 B. B. 67 C. C. 68 D. D. 69 E. E. 70 F. F. 71 G G 72 H H 73 I. I. 74 J J 75 K K 76 L. L. 77 M. M. 78 N N 79 O O 80 P P 81 Q Q 82 R. R. 83 S. S. 84 T T 85 U U 86 V V 87 W. W. 88 X X 89 Y Y 90 Z Z 91 [ % K 92 \ % L 93 ] % M 94 ^ % N 95 _ %O

No character Coding 96 ` % W 97 a + A 98 b + B 99 c + C 100 d + D 101 e + E 102 f + F 103 G + G 104 H + H 105 i + I 106 j + J 107 k + K 108 l + L 109 m + M 110 n + N 111 O + O 112 p + P 113 q + Q 114 r + R 115 s + S 116 t + T 117 u + U 118 v + V 119 w + W 120 x + X 121 y + Y 122 z + Z 123 { % P 124 % Q 125 } % R 126 ~ % S 127 DEL % T,% X,% Y,% Z

Code 39 reduced

Is a variant that only consists of the characters 0 to 9 and A to Z and the test character is calculated modulo 36.

support

As a tried and tested symbolism, Code 39 is supported by almost all common bar code readers and label printers. For word processing software, Code 39 is offered as a font from various providers (also free of charge), and the barcodes package is recommended for LaTeX .

Web links

• Free Code 39 font and Excel macro for automotive suppliers' goods tags
• Download option of Code 39 as a TrueType font
• EAN MediaWiki extension , a MediaWiki extension that visually displays Code 39 / Codabar / UPC / EAN-13 / EAN-8 barcodes only by specifying the barcode number / symbols.
• ISO / IEC 16388: Information technology - Automatic identification and data capture techniques - Code 39 bar code symbology specification
• Barcode lexicon Code 39

Individual evidence

1. ↑ ISO / IEC 16388: 2007 Information technology - Automatic identification and data capture techniques - Code 39 bar code symbology specification International Organization for Standardization , Retrieved March 10, 2014
2. ↑ Barcode systems Code 39 ( Memento from March 31, 2015 in the Internet Archive ). Barcode service Michael Franken . Retrieved March 10, 2014.
3. ↑ Barcode systems Code 39 - test character calculation (description) ( Memento from March 31, 2015 in the Internet Archive ). Barcode service Michael Franken . Retrieved March 10, 2014 - with a similar calculation
4. ↑ Barcode Lexicon Code 39 - advantages / strengths. Suchy MIPS . Retrieved March 10, 2014.
5. ↑ Barcode systems Code 39 - test character calculation (description) ( Memento from March 31, 2015 in the Internet Archive ). Barcode service Michael Franken . Retrieved March 10, 2014. - Table lists the special characters