Rockwell Automation 2755 Enhanced Decoder Series B - Manual (Page 97)

7–9 Configuration: Scanner Control, Primary Match Table, Discrete I/O
Publication 2755-833
Laser Light
Refer to Laser Light under Scanner A Parameters earlier in this
section for information on Scanner B laser light control.
Decode Mode
Field Type Options
Select
Coordinated 1
Coordinated 2
Package Detect
Host
Sets the decode mode for Scanner B. The options are Coordinated 1,
Coordinated 2, Package Detect, and Host. The default is
Coordinated 1.
If you set the scanning mode to either Coordinated mode, Scanner B
operates in concert with Scanner A, and both scanners use the trigger
specified for Scanner A. The Trigger Timeout parameters is not
used when Scanner B operates in coordinated mode.
If you use one of the independent decode modes (either Host or
Package Detect), Scanner B will operate independently of Scanner A
and use its own trigger source. If the Decode Mode is package
detect; decoding is triggered by the Scanner B package detect signal.
If the Decode Mode is host, decoding is initiated by the Scanner B
Start Character and concluded by the Scanner B Stop Character.
In the Coordinated modes, the Symbols/Package setting can be
satisfied by either or both scanner(s). For example, the
Symbols/Package setting is 2. Scanner A can decode one valid
symbol and Scanner B can decode one valid symbol to produce a
valid read, or both symbols can be read from either scanner. The
difference between the two coordinated modes is in how each
defines what constitutes a unique decoding event within a package.
•
In Coordinated 1 mode (source dependent), the decoder always
considers the source of the data as well as its content. Data will
be treated as unique if it originates from different scanners, or if
the value or symbology is different.
•
In Coordinated 2 mode (source independent), the decoder will
consider data to be unique only when its value or its symbology is
different. Identical data originating from different scanners will
be treated as a single decode (and the second decode is ignored).