Technical data

164 • MODBUS Functions
Internal Variables
WAGO-I/O-SYSTEM 750
ETHERNET TCP/IP
Register address 0x1005 (MODBUS Address 404102)
Designation Watchdog stoppen, WD_AC_STOP_MASK
Access read / write
Default 0x0000
Description This register is used to stop the watchdog timer by entering a value of
0xAAAA followed by 0x5555.
Register address 0x1006 (MODBUS Address 404103)
Designation While watchdog is running, WD_RUNNING
Access read
Default 0x0000
Description Current watchdog status.
at 0x0000: Watchdog not active,
at 0x0001: Watchdog active.
at 0x0002: Watchdog exhausted.
Register address 0x1007 (MODBUS Address 404104)
Designation Restart watchdog, WD_RESTART
Access read / write
Default 0x0001
Description This register restarts the watchdog timer by writing a value of 0x1 into it.
If the watchdog was stopped before the overrun, it is not restarted.
Register address 0x1008 (MODBUS Address 404105)
Designation Simply stop watchdog WD_AC_STOP_SIMPLE
Access read / write
Default 0x0000
Description This register stops the watchdog by writing the value 0x0AA55 or 0X55AA
into it. The watchdog timeout fault is deactivated and it is possible to write in
the watchdog register again. If there is an existing watchdog fault, it is reset
Register address 0x1009 (MODBUS Address 404106)
Designation Close MODBUS socket after watchdog timeout
Access read / write
Description 0 : MODBUS socket is not closed
1: MODBUS socket is closed
Register address 0x100A (MODBUS Address 404107)
Designation Alternative watchdog
Access read / write
Default 0x0000
Description
This register provides an alternate way to activate the watchdog timer.
Proceedure: Write a time value in register 0x1000; then write a 0x0001 into
register 0x100A. With the first MODBUS request, the watchdog is started.
The watchdog timer is reset with each Modbus/TCP instruction. If the watch
dog times out, all outputs are set to zero. The outputs will become
operational again, after communications are re-established.
All register data is in word format.