At run time the control list selector is highlighted to show the state with a value that matches the Value connection value at the data source. The operator can scroll through the list to select a different state. The value assigned to the selected state is written to the Value connection.
Tip: |
In the control list selector, when you scroll to a state and select it, it takes a specific period of time for the system to write the value and make the state selected. |
If auto repeat is set up for the key button (on the key button's Timing tab) and the operator holds down the Move Up or Move Down button for the specified Auto repeat delay time, the list begins to scroll. If "Write on enter" is not selected, the application attempts to send a value to the Value connection for each state that scrolls by. However, some values may be lost if the Auto repeat rate is too fast for all the values to register.
When you open a display at run time, the application reads the Value connection value and highlights the state with the matching value. If no state matches the Value connection value, no state is highlighted and the cursor appears at the top of the list.
The application periodically reads the Value connection and highlights the state with the matching value. If no state matches the Value connection value, no state is highlighted and the cursor remains beside the previously highlighted state.
The frequency with which the application updates the control list selector depends on the update rate for the tag assigned to the Value connection.
When the operator moves to a new state that has an invalid value and presses Enter, the cursor moves but the state is not highlighted.
Causes of run-time errors for the control list selector