Register 0X1104 - Watchdog Operation Mode; Table 213: Watchdog Configuration - WAGO 750-8207 Manual

300 MODBUS – CODESYS 2
The register can be read and written in the states
WATCHDOG_UNCONFIGURED, WATCHDOG_STOPPED and
WATCHDOG_EXPIRED. However, if the watchdog is active
(WATCHDOG_RUNNING state), this register can only be read. The response to
a write operation is an ILLEGAL_FUNCTION (0x01) exception.

Table 213: Watchdog Configuration

Bit Name/Bit Identifier
0 EXPLICIT_
TRIGGER_ONLY
1 TRIGGER_ON_
STATUS_REG
2 CLOSE_ALL_TCP_
CONNECTIONS
* Default setting
The individual options are activated when the specific bit, or bit combination, is
set.
10.5.5 Register 0x1104 – Watchdog Operation Mode
This register contains the value for the watchdog operation mode.
The register can be both read and written irrespective of the watchdog status.
The following operation modes are possible:
Manual
Draft version 1.2.1 from 2017-09-13, valid from FW Version 02.06.20(09)
750-8207 PFC200 CS 2ETH RS 3G
Explanation
Activates the Explicit Trigger mode
0* All valid MODBUS requests are considered as
watchdog triggers. The only exception is the
access to the register 0x1101 (Watchdog Status).
1 Only the writing of register 0x1100 (Watchdog
Command) with the value 0x5555
(WATCHDOG_START) is considered as a
watchdog trigger. The access to the register
0x1101 (Watchdog Status) is also an exception
here.
Activates the watchdog trigger by (read) access to
register 0x1101 (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.
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.
WAGO-I/O-SYSTEM 750