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Security monitor – National Instruments BridgeVIEW User Manual

Page 372

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Appendix A

HMI Function Reference

BridgeVIEW User Manual

A-52

© National Instruments Corporation

Security Monitor

Use this VI to monitor the access level of the current BridgeVIEW operator. By default, this
VI times out after one second, returning to the current operator access level. When an operator
logs in, this VI returns immediately.

timeout (secs) (1) specifies how long to wait for a user to log in.

visibility access level (0) determines the value of “Visible” attribute
setting
. If the current operator access level is greater than or equal to
visibility access level, the “Visible” attribute setting indicator is TRUE.
Otherwise, “Visible” attribute setting is FALSE.

operability access level determines the value for the “Disabled” attribute
value
output. If the current operator access level is greater than or equal to
operability access level, “Disabled” attribute value is

0

(enabled).

Otherwise, “Disabled” attribute value is

1

(disabled) or

2

(grayed out),

depending on the setting of the gray out on disable input.

gray out on disable (T) determines if the “Disabled” attribute value is

1

(disable) or

2

(disable and gray out) if a user access level is not greater

than or equal to operability access level.

“Visible” attribute setting is the value to send to the “Visible” attribute
of the control or indicator to which security is applied.

“Disabled” attribute value is the value to send to the “Disabled” attribute
of the control or indicator to which security is applied.

shutdown indicates that the BridgeVIEW Engine is shutting down.

Note

When you use this VI in your operator interface loops, you do not want the timeout
value to be too long, or your front panel can take a long time to finish execution.
Similarly, setting
timeout to 0 seconds degrades the overall performance of your
interface because this VI is called too often, too quickly.