Trigger ending conditions, Response modes – Rockwell Automation 2755-DM9, -DM9E High Speed Decoder User Manual

Page 27

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Chapter 3
How the Decoder Operates

3–8

In the triggered mode of operation, there are three possible trigger sources:

Host command - The command is generated by a host computer or
programmable controller.

Package detect - A package detector connected to the scan head is the
source for the trigger.

Internal timer - The internal timer cycles the trigger from on to off based
on a timed interval.

When a trigger on is received, the decoder will continuously attempt to
decode bar codes until one of the following trigger ending conditions occurs:

(a) The number of fields (bar codes) per package count is satisfied.

(b) A trigger off command is sent by a host device.

(c) Package detect signal is no longer present.

(d) The internal timer (No-Read timer) times out.

In the triggered mode of operation there are two options which determine
when the decoder will send bar code information to a host and/or operate
discrete outputs:

After Valid Package - A valid package is a package that has valid bar
code symbols and meets the fields (bar codes) per package count
(condition

(

a

)

listed above).

End of Trigger - Refer to trigger ending conditions (b, c, d) listed above.

Trigger Ending Coditions

Response Modes

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