304 Modbus – CODESYS 2
WAGO I/O SYSTEM 750 XTR
750-8202/040-001 PFC200 2ETH RS TELE XTR
Manual
Version 1.2.0, valid from FW Version 03.01.07(13)
9.5.3
PLC Status Register
Register 0x1040 provides the status (state) that the controller is currently in.
Possible values:
1 = PLC running − PLC status is RUNNING.
2 = PLC stopped − PLC status is STOPPED.
9.5.4
Modbus Watchdog
The Modbus watchdog monitors in the Modbus slave the ongoing Modbus
communication with the Modbus master. All valid Modbus requests of a Modbus
master from all the services supported by the Modbus slave are trigger events
(see chapter “Modbus Mapping”). This does not apply to the Explicit Trigger
mode and the access to the register 0x1101 (Watchdog Status), which can be
configured via the 0x1103 (Watchdog Config) register.
If no trigger occurs during the watchdog within the timeout time set in the 0x1102
register (Watchdog Timeout), the “Watchdog Timeout” response is initiated. The
closing of all Modbus TCP connections can be configured as a response, see
register 0x1103 (Watchdog Config).
The Modbus watchdog supports two different functions
STANDARD_WATCHDOG and ALTERNATIVE_WATCHDOG. The operation
mode can be selected via the register 0x1104 (Watchdog Operation Mode).
The following diagrams show the possible states of the Modbus watchdog and
status transitions for the particular operation mode.
Figure 100: State Diagram, STANDARD_WATCHDOG Operation Mode
