|
|
|
|
|
Control-O rule utilization consists of three phases. Control-O rules are ordered, activated, and triggered as described below.
When Control-O is brought up, rules in tables specified in the Control-O procedure are automatically ordered depending on their basic scheduling criteria. Rule tables can be also manually ordered or forced at any time through the Table List screen or an operator command. The ordering or forcing of rules places them in the memory of the Control-O monitor.
Ordered or forced rules are now eligible for activation. Control-O monitors the IOA environment and activates rules when their runtime scheduling criteria are satisfied. Runtime scheduling criteria can, for example, make rule activation dependent upon specific prerequisite conditions, or they can limit the activation of the rule to a specific time period. For more information, see Runtime Scheduling Parameters, and Runtime Scheduling Parameters – Summary.
Activated rules are eligible for triggering. A rule is triggered by an occurrence of the message, command or event specified in the ON statements in the rule. When a rule is triggered, the actions defined in the rule are performed. For more information, see ON Statement: Message/Event Selection Parameter.
Note: Only a currently activated rule can be triggered. If the runtime scheduling criteria for an activated rule are no longer satisfied, the rule is deactivated, and cannot be triggered.
Parent Topic |