National Instruments BridgeVIEW 用户手册

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Appendix A
HMI Function Reference
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.