Datamax-O'Neil APEX Series Programmer’s Manual User Manual

Page 18

Code 128 Specifications

Description

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

Character set

Support for full 256 ASCII set among three subsets

Elements per
symbol

6 (3 bars, 3 spaces)

Character density

9.1 CPI

Bar width

0.25mm

Characters per line

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:

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

Start Character

Characters Sent to Printer

Characters Read by Bar Code Reader

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

IF is 0x87 CODE A

0x040 through 0x07F ASCII
(#64 - #127)

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

IF is 0x88 CODE B

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

IF is 0x89 CODE C
(Each number must be paired with another)

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

Code 128 Data Bytes:

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

0x081

129

FNC 2

0x082 130 SHIFT

SHIFT

0x083

131

change to C

0x084

132

change to B

FNC 4

change to B

0x085

133

FNC 4

change to A

0x086

134

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).

This manual is related to the following products:

ANDES Series Programmer’s Manual