296 MODBUS – CODESYS 2
WAGO-I/O-SYSTEM 750
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)
Figure 109: State Diagram, ALTERNATIVE_WATCHDOG Operation Mode
The state diagram for the ALTERNATIVE_WATCHDOG operation mode shows
that the watchdog is always active as soon as a timeout time > 0 is set in the
register 0x1102 (Watchdog Timeout). The writing of commands in the register
0x1100 (Watchdog Command) is limited in this operation mode. Only the
WATCHDOG_START command is permitted as a possible trigger. The only
possibilities to deactivate or stop the watchdog in ALTERNATIVE_WATCHDOG
mode are the setting of the timeout register to 0 after the timeout has elapsed
and the switching back to the STANDARD_WATCHDOG operation mode.
The following diagram shows the possible state transitions when operation
modes are switched.