The Modbus event record structure is located at addresses 49251...49262.
| Address | Register | Values | Comment |
|---|---|---|---|
| 49251 | Event selection |
1...5 and -1...-499 |
Write register |
| 49252 | Sequence Number | 0...65535 | |
| 49253 | Unread records left | 0...499 | |
| 49254 | TimeStamp (Year,Month) | High byte:year, low byte:month | |
| 49255 | TimeStamp (Day, Hour) | High byte:day, low byte:hour | |
| 49256 | TimeStamp (Min, Sec) | High byte:min, low byte:second | |
| 49257 | TimeStamp (Milliseconds) | Word: milliseconds (0...999) | |
| 49258 | Event type | See separate description | |
| 49259 | Data Object ID 1 | 0 or UID high word | See separate description |
| 49260 | Data Object ID 2 | Modbus address or UID low word | |
| 49261 | Data Value | Modbus data value | Value into which object has changed |
| 49262 | Data Value | Additional data |
The event record can have two different data object identification alternatives. The data object can be identified by the Modbus address where the object resides or it can be identified by a unique id which is platform dependent.
The identification alternative is selected with the Modbus parameter Event ID.