Datamax-O'Neil Class Series Programmer’s Manual User Manual
Page 197
Appendix G – Barcode Details
Class Series Programmer’s Manual
183
Subset A: Includes all of the standard uppercase alphanumeric keyboard characters plus the control
and special characters. To select Code 128 Subset A, place an ASCII A (DEC 65, HEX 41) before the
data to be encoded.
Subset B: Includes all of the standard uppercase alphanumeric keyboard characters plus the
lowercase alphabetic and special characters. To select Code 128 Subset B, place an ASCII B (DEC
66, HEX 42) before the data to be encoded. If no start character is sent for the Code 128 font, Code
128 Subset B will be selected by default.
Subset C: Includes the set of 100 digit pairs from 00 through 99 inclusive, as well as special
characters. Code 128 Subset C is used for double density encoding of numeric data. To select Code
128 Subset C, place an ASCII C (DEC 67, HEX 43) before the data to be encoded. Subset C can only
encode an even number of numeric characters. When the data to be encoded includes an odd number
of numeric characters, the last character causes the printer to automatically generate a ‘switch to
subset B’ and encode the last character appropriately in subset B.
Special Character Handling: Characters with an ASCII value greater than 95 are considered special
characters. To access these values, a two-character reference table is built into the printer (see below).
For example, to encode FNC2 into a Code 128 Subset A bar code, send the ASCII “&” (DEC 38,
HEX 26) followed by the ASCII “B” (DEC 66, HEX 41).
Sample: ATEST&B123
Encoded:
TEST<FNC2>123
ASCII
2 CHAR
CODE A
CODE B
CODE C
96 &A
FNC3
FNC3
-NA-
97
&B
FNC2
FNC2
-NA-
98 &C
SHIFT
SHIFT
-NA-
99
&D
CODEC
CODEC
-NA-
100 &E
CODEB
FNC4
CODEB
101
&F
FNC4
CODEA
CODEA
102 &G FNC1
FNC1
FNC1
Table G-1: Special Character Handling
Control Codes: By sending these control codes, control characters can be encoded into a Code 128
Subset A bar code (e.g., ABC{DE will be encoded as ABC<ESC>DE):
Control Code in the Bar Code Data Stream
Encoded Control Character Result
` NUL
a through z
1 - 26
{ ESC
| FS
} GS
~ RS
ASCII 127
US
The following example prints a Code 128 bar code:
<STX>L
D11<CR>
1E000000015010001234567890<CR>
121100000000100Barcode E<CR>
E