Specifications

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Dual Decoder System
The dual decoder system integrated in the terminal initially decodes a scanned bar code data using
the standard decoder, but if the decoding fails, it will use the additional decoder described below
to decode the same bar code data. This dual decoders system supports the bar code symbologies
listed below.
- Code39 symbology
- Code128 symbology
- EAN symbology
With the decoding system used for the previous CASIO handheld terminals, decoding is processed
with a mean value of one module adding bar thickness of each black bar and white bar for one
character when performing binaryzation or quardruplzation of bar thickness. However, this
method does not accurately decode a bar code if it is formed with unbalanced bar thickness
between white bars and black bars.
The dual decoder system can solve it by calculating separately each mean value of black bars and
white bars for such a bar code with unbalanced thickness of white and black bars by changing the
threshold level of decoding.
Customizing the Decoder
According to the scan environment and the bar code printed material’s quality, the integrated
decoder can be customized for efficient scanning performance. First, to maintain scanning
performance with the ordinary decoding logic, perform decoding using the decoder and if it does
not succeed, customize it by tuning the elements in the table below so that the decoding can be
performed better.
Table 3.42 Customizing the elements
Element Description
Change margin of the right/left
threshold values
Used to change the threshold values for right and left side marginal
spaces of a bar code symbol printed inside quadrangle.
Used to thicken or thin each bar of a bar code symbol for a specified
value and then decode it.
Change of compensation values
of the thickness of bars of a bar
code symbol.
Value for thickening or thinning bars that form a bar code symbol can be
changed.