In the Context Help window, which you can
access by selecting Help>>Show Context Help
required terminals appear bold, recommended terminals appear
as plain text, and optional terminals appear dimmed. The
labels of optional terminals do not appear if you click the
Hide Optional Terminals and Full Path button in
the Context Help window.
You can designate which inputs and outputs are required,
recommended, and optional to prevent users from forgetting to
wire subVI terminals.
Right-click a terminal in the connector pane and select
This Connection Is from the shortcut menu. A
checkmark indicates the terminal setting. Select
Required, Recommended, or Optional
.
For terminal inputs, required means that the block diagram on
which you placed the subVI will be broken if you do not wire
the required inputs. Required is not available for terminal
outputs. For terminal inputs and outputs, recommended or
optional means that the block diagram on which you placed the
subVI can execute if you do not wire the recommended or
optional terminals. If you do not wire the terminals, the VI
does not generate any warnings.
LabVIEW sets inputs and outputs of VIs you create to
Recommended by default. Set a terminal setting to
required only if the VI must have the input or output to run
properly. Refer to the Read File function located on the
Functions>>All Functions>>File I/O palette for
examples of required, recommended, and optional inputs and
outputs.
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