User guide

Bar Code Printing on the LA600 MultiPrinter
20.6 Bar Code Characteristics
20.6 Bar Code Characteristics
This section describes how the LA600 MultiPrinter supports the various bar
code characteristics.
20.6.1 Start and Stop Codes
In a bar code, the Start and Stop characters identify, respectively, the beginning
and end of the bar code symbol to the bar code reader:
• For horizontal bar codes (composed of individual bars in portrait
orientation), the Start code is positioned at the left end of the symbol,
before the most significant character of the bar code. The Stop code
is positioned at the right end of the symbol, after the least significant
character.
• For vertical bar codes (composed of individual bars in landscape
orientation), the Start code is at the bottom and the Stop code is at
the top.
The LA600 MultiPrinter generates Stop and Start characters automatically,
precluding the need to program these codes in the application.
20.6.2 Parity and the Center Code
In the bar code styles EAN 8, EAN 13, UPC A, and UPC E, which use only the
characters 0 through 9, an individual character is sent in either odd or even
parity, in order to expand the number of unique patterns possible. In these
bar code styles, the Center code is used to divide the characters on the left,
typically sent in odd parity, from those on the right, sent in even parity. With
this approach, a digit that appears on both sides of the Center code can have a
bar code pattern on the left that differs significantly from its bar code pattern
on the right.
The LA600 produces the Center code automatically; it does not have to be
programmed by the application.
20.6.3 Quiet Zone
‘‘Quiet zones’’ are completely blank areas at least .25 inches wide before and
after a bar code structure. Quiet zones ensure the accurate reading of the
Start and Stop codes, and prevent adjacent bar codes from overlapping.
The operator is responsible for providing sufficient space on the form for the
quiet zones.
Bar Code Printing on the LA600 MultiPrinter 20–13