Scanning Mode Options; Scanning Pdf417 Bar Codes - Symbol PDT 7500 Series Product Reference Manual

PDT 7500 Series Product Reference Guide for DOS
For best operation in Smart Raster mode, keep the scan pattern as parallel to the symbol's
rows as possible, keep the scanner as still as possible, and hold the scanner at an angle which
does not give specular reflection (refer to Angle on page 4-6). The symbol should also be in
good condition.

Scanning Mode Options

There are three scanning options: aiming with a dot pattern, scanning with a slab raster
pattern, or always raster.
Aiming Dot Option
A trigger pull creates the single dot aiming pattern, which lasts for a fixed interval. This dot
easily can be seen in outdoor or high ambient light environments. A slab raster pattern or an
open raster pattern appears next, depending on the programmed scanning option. There are
two programmable timeout periods for this option — normal and extended.
Slab Raster Aiming Option
A trigger pull creates the slab raster pattern. If the target is a 1-D bar code, the slab pattern
decodes the bar code. If the target bar code is PDF417, the pattern opens up to an optimized
raster pattern as soon as the scanner is properly aligned over the bar code.
Always Raster Option
When programmed to this option, the PDF417 scan element directly opens to a full raster
pattern whenever the trigger is pulled.

Scanning PDF417 Bar Codes

Make sure the terminal is programmed for a slab raster aiming pattern and Smart Raster
mode.
1. Aim the scanner at the symbol. Try to keep the nose of the scanner parallel with the
symbol's rows.
2. Make sure the symbol you want to scan is within the scanning range; refer to the 1-
D/PDF417 decode zones. Then pull the trigger.
The scan pattern first covers the symbol horizontally (Figure 4-2). Make sure the
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