Discrete attribute runtime behavior: general

Input processing (when Input is configured)

• Get input value and set Field Attribute value.

• If the input source supports a time stamp, the PV is updated with the value, time stamp, and quality (VTQ) of the source attribute. If the input source does not support a time stamp, the value and quality of the source attribute is used, and a time stamp of the current time is generated for any change in source attribute's value or quality. If the quality of the Value attribute changes, the time stamp is updated to the current time.

• If state labels are configured, map Field Attribute value to the corresponding configured state and set [FieldAttribute].Msg.

• If alarming, then calculate the alarms.

Statistics processing (when Statistics are enabled)

• Calculate the durations for the current time and total time that the Discrete Field Attribute was in the State0, State1, and Passive states.

• If the Field Attribute value has just changed to a new state, increment the counter for the new Field Attribute value state.

• Detect the duration alarms for the State0 state total duration and State1 state total duration.

Alarm processing

• Get input value and compare with ActiveAlarmState.

• If the value matches with ActiveAlarmState, then set Alarm.Condition to TRUE.

• If the value does not match, then clear Alarm.Condition.