Technical data

MODBUS Functions • 163
Internal Variables
WAGO-I/O-SYSTEM 750
ETHERNET TCP/IP
Register address 0x1001 (MODBUS Address 404098)
Designation Watchdog function coding mask, function code 1...16, WDFCM_1_161...16
Access read / write
Default 0x0000
Description Using this mask, the specific function codes can be configured to reset the
watchdog function. The function code can be selected by writing a ‘1’ to the
appropriate bit(s) ( 2
(Funtion code-1) +
2
(Funtion code-1...
).
Bit 1001.0 corresponds to function code1,
Bit 1001.1 corresponds to function code2...
A value of 0xFF enables Modbus functions code 1 through 16 to reset the
watchdog. It is not possible to modify this value while the watchdog is
running.
Register address 0x1002 (MODBUS Address 404099)
Designation Watchdog function coding mask, function code 17...32, WD_FCM_17_32
Access read / write
Default 0x0000
Description Same function as above, however, with the function codes 17 to 32. These
codes are currently not supported, for this reason the default value should not
be changed.. It is not possible to modify this value while the watchdog is
running.
Register address 0x1003 (MODBUS Address 404100)
Designation Watchdog-Trigger, WD_TRIGGER
Access read / write
Default 0x0000
Description This register is used to trigger the watchdog. The default value after power up
is 0. The writing of a non zero value will trigger the watchdog. The watchdog
is triggered each time the contents of this register are modified. The watchdog
cannot be triggered if the watchdog timer register is set to 0.
Register address 0x1004 (MODBUS Address 404101)
Designation Minimum current trigger time, WD_AC_TRG_TIME
Access read / write
Default 0xFFFF
Description This register stores the time value for the shortest remaining watchdog
duration. The default value is 0xFFFF. When the watchdog timer is triggered,
this register is continuously compared to the remaining watchdog time, and the
lesser of the two values is stored in this register. If the value in this register is
0, a watchdog fault has occured.