Rockwell Automation PLC-5 Fieldbus Solutions for Integrated Architecture User Manual - Manual (Page 81)

Publication 1757-UM006A-EN-P - May 2002
Integrating Fieldbus into Rockwell Automation Logix System 2-37
The alert object contains information from an alarm or update event
object, which is to be sent in the notification message. The alert object
will be invoked by the alert notification task. If multiple alarms or
event parameters are unreported, then the one with the highest
priority or is the oldest of equal priority will be selected by the alert
notification task.
The selected alert object is sent in a message at the first opportunity -
less than the alert confirm time. If a confirmation from an interface
device is not received by the alarm notification routine in the field
device within a time determined by the resource block confirm time
parameter, then the alert will be considered unreported so it may be
considered for selection.
11 UPDATE - Link associated with function block
12 UPDATE - Trend associated with block
Message type will be enumerated in the following manner:
0 =
1 = Event Notification
2 = Alarm Clear
3 = Alarm Occur
Table 2.M Standard type valid values
Valid Values Meaning