11
3.3 Using Status Event Exchanges and Event Logs
3.3.1 Configuring Event Exchanges
The Data server can provide recording binary events asserted by the connected devices and give a
notification to the eXpertPower server.
The Data server can periodically poll device status registers and detect a change in the status bits to
recognize asserted device events. A binary event mask specifies the critical event bits. Whenever the
Data server detects a change in the status bits selected by the event mask, it records an event record to
the circular Event log file. If the eXpertPower service is enabled in the ETC2002, this event will initiate
a connection to the eXpertPower server.
Polling status events is performed via the status event exchanges. The Data server provides up to 250
event exchanges, each one of 1 register long, with a separate event mask. Table 3-6 shows the setup
parameters that are used for configuring status event exchanges.
Table 3-6 Status Event Exchange Setup
Description Range
Exchange number
0-249
Device status register address
0-65535
Event mask 0x00000000–0x0000FFFF
Device ID
1-247
Polling enabled
1=enabled, 0=disabled
Options flags:
Bit 0 – Auto reset enabled (1=enabled, 0=disabled)
Bit 1 – Register type:
0=coils (Modbus request type 1)
1=holding register (Modbus request type 3)
The Data server supports the auto reset option you can use to clear a latched device status register
after it has been read. In most devices, critical events are latched into a status register, so the new
events are not generated until the register is explicitly cleared by a master application.
Since status registers may be implemented in the device either as coils, or as holding registers, you
should specify a register type for each event exchange via the option flags.
3.3.2 Accessing the Event Log File
All event records are stored in a single circular event log file. Along with device status events, the file
may contain the ETC2002 self-diagnostic events.
File transfers are performed through two blocks of registers: a master request block and a read-only file
transfer block. The file transfer block occupies 12 registers in the address range of 10000-10011. Tables
3-7 and 3-8 show a layout of the event log request block and a layout of the event log record.
Table 3-7 Event Log Request Block
Description Range
Function
3 = set file position
5 = reset file position
11 = read record
Record sequence number (with functions 3, 11)
0-65535
Table 3-8 Event Log Record Layout
Description Range
Event Log status
0 = no new events, 1 = have new events,
-1 = record corrupted
Event sequence number
0-65535
Event type ID
F2 (See Section 5)
Device ID
0-247
Event time, seconds since 1/1/1970
F1 (See Section 5)
Event data
F3 (See Section 5)