Datamax 7A300007 Rev. 2 Code 128 Specifications, Description Character set Elements per symbol

Code 128 Specifications

Description

Character set

Elements per symbol

Character density Bar width Characters per line

Each symbol starts with Leading Quiet Zone, followed with Start Symbol, Data Symbols, ending with Stop Symbol and Trailing Quiet Zone

Support for full 256 ASCII set among three subsets 6 (3 bars, 3 spaces)

9.1CPI 0.25mm

2 Inch printer: 13 alphanumeric characters or 26 numeric only (maximum) - automatically centered

3 Inch printer: 18 alphanumeric characters or 36 numeric only (maximum) - automatically centered

4 Inch printer: 32 alphanumeric characters or 36 numeric only (maximum) - automatically centered

Code 128 Start Character:

<start character> = {0x87, 0x88, 0x89} determines the character set to be printed

Start Character			Characters Sent to Printer
IF	<start character> is 0x87 CODE A		0x020 through 0x03F ASCII
			(#32 - #63)
			0x040 through 0x07F ASCII
			(#64 - #127)
IF	<start character> is 0x88	CODE B	0x020 through 0x07F ASCII
			(#32 - #127)
IF	<start character> is 0x89	CODE C	PAIRS 0x030 through 0x039 ASCII
(Each number must be paired with another)			(#48 - #57)

Code 128 Data Bytes:

<DATA>

Characters Read by Bar Code Reader

0x020 through 0x03F ASCII (#32 - #63)

0x00 through 0x07F ASCII (#0 - #31)

0x020 through 0x07F ASCII (#32 - #127)

PAIRS 0x030 through 0x039 ASCII (#48 - #57)

The data bytes are defined by which character set is defined. The printer accepts all characters 0x20h - 0x7Fh with the translations defined above.

Also, characters 0x080 - 0x86 may be used as Code 128 control characters:

HEX	DEC	CODE A	CODE B	CODE C
0x080	128	FNC 3	FNC 3
0x081	129	FNC 2	FNC 2
0x082	130	SHIFT	SHIFT
0x083	131	change to C	change to C
0x084	132	change to B	FNC 4	change to B
0x085	133	FNC 4	change to A	change to A
0x086	134	FNC 1	FNC 1	FNC 1

FNC 1: Reserved CODE 128 character (used for UCC/EAN128)

FNC 2: Message append (not supported by all bar code readers)

FNC 3: Initialize bar code reader

FNC 4: Extend characters (bar code reader reads character + 128)

For example: 'a' is changed from #97 to #97+128 = #225

Note that it is possible to switch code sets in the middle of the bar code. This is useful with heavily numeric alphanumeric bar codes (see example below).

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