WAGO-I/O-SYSTEM 750
MODBUS – e!RUNTIME 313
750-8207 PFC200 CS 2ETH RS 3G
Manual
Draft version 1.2.1 from 2017-09-13, valid from FW Version 02.06.20(09)
11.2.1.4 Register 0xFA03 – Watchdog Config
This register contains the configuration parameters for the watchdog. The
register is organized in bits, see following table.
The register can be read and written irrespective of the watchdog state in the
SIMPLE_WATCHDOG operation mode.
However, in the ADVANCED_WATCHDOG operation mode, the register can only
be read and written in the WATCHDOG_UNCONFIGURED and
WATCHDOG_STOPPED states.
If the watchdog is active (WATCHDOG_RUNNING or WATCHDOG_EXPIRED
state), only a read access is permissible. The response to a write request in this
case is an ILLEGAL_FUNCTION (0x01) exception.
Table 219: Watchdog Configuration
Bit Name/Bit Identifier Explanation
0 EXPLICIT_
TRIGGER_ONLY
Activates the Explicit Trigger mode
0* All valid MODBUS requests are considered as
watchdog triggers. Access to register 0xFA02
(Watchdog Status) is the only exception.
1 Only the writing of register 0xFA00 (Watchdog
Command) with the value 0x5555
(WATCHDOG_START) is considered as the
watchdog trigger. The exception is also here the
access to the register 0xFA02 (Watchdog
Status).
1 TRIGGER_ON_
STATUS_REG
Activates the watchdog trigger by (read)
access to register 0xFA02 (Watchdog Status)
0* The reading of the watchdog status is not
considered as a watchdog trigger.
1 The reading of the watchdog status triggers the
watchdog.
2 CLOSE_ALL_TCP_
CONNECTIONS
Activates the closing of all MODBUS TCP
connections with the expiry of the timeout (transition
to WATCHDOG_EXPIRED state)
0 Existing MODBUS TCP connections remain
open.
1* All existing MODBUS TCP connections are
closed.
7 SELECT_
ADVANCED_
SIMPLE_MODE
Determines the watchdog operation mode
0* Advanced Mode: The watchdog must be
controlled explicitly via commands (see register
0xFA00 Watchdog Command).
1 Simple Mode: The watchdog is activated directly
with a timeout > 0 in register 0xFA01 (Watchdog
Timeout). Each trigger restarts the running as
well as the expired watchdog. The watchdog can
only be stopped by switching to Advanced mode.