CognitiveTPG A776 ColorPOS, Programming Manual

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Chapter 5: Programming commands 102
A776 (B780) Programming Guide A776-PG00001 D 07/13
Each character has four bars and four spaces within 17 modules, and is assigned a value between 0 and 928. For this
symbology, it is common to refer to these character values as “code words.”
There are three mutually exclusive sets of symbol patterns, or clusters, each having 929 distinct patterns. Because
different clusters are used for adjacent rows, it is possible for the decoder to tell if the scanning path is crossing row
boundaries without the use of separator bars.
Sample symbol description:
Each PDF 417 symbol consists of 3 to 90 stacked rows surrounded on all four sides by a quiet
zone. Each row contains:
1
Leading quiet zone
2
Start pattern
3 Left row indicator characters (code words)
4 One to thirty data characters (code words)
5
Right row indicator character (code words)
6
Stop pattern
7 Trailing quiet zone
The number of characters in a row and number of rows can be adjusted to vary the symbol’s overall aspect ratio to best
fit an available space.
Each row has a left and right row indicator with a data region between. The left-most character in the top row of the
data region is the total number of characters in the data region, excluding error correction characters. Characters
within the data region are designed to be read from left to right, starting on the top row, immediately after the length-
defining character. The maximum characters in the data region are 928.
Related Information:
The “Set bar code width” command (1D 77 n) affects the x dimension and row height for PDF 417. See chart below.
n value x dimension row height
2 2 7
3 3 10
4 4 13
5 5 17
6 6 20
Select bar code width
ASCII
GS w n
Hexadecimal 1D 77 n
Decimal
29 119 n
Value of n: 2, 3, 4, 5, 6
Default:
3 for receipt; 2 for slip
Sets the bar code width to n dots.
Formulas
n /8 mm ( n /203 inch) for receipt.
n /5.7 mm ( n /144 inch) for slip.