Mitsubishi Electric Q80BD-J61BT11N, User Manual

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MELSEC
4 FUNCTIONS
4.3.5 Monitoring the operation of the software (operating system, driver) inside the hardware
(Driver WDT function)
Driver WDT function monitors the operation of the software (operating system, driver)
inside the hardware by the timer function on CC-Link Ver.2 board.
When the driver cannot reset the timer of the board within the specified driver WDT
monitoring time, CC-Link Ver.2 board detects driver WDT error.
Driver WDT function detects driver operation delay due to the access error from the
driver to CC-Link Ver.2 board or system high load.
(1) Driver WDT settings
For the setting method, refer to section 8.2.5.
REMARK
The driver WDT function is set to invalid as a default.
(2) When the driver WDT error has occurred
The following shows the operation when driver WDT error has occurred.
1) CC-Link Ver.2 board and the driver stop link refresh and communication and
are disconnected from the network in order to avoid an erroneous output.
A CPU stop error occurs when checking the CC-Link Ver.2 board from other
station on which the driver WDT error has occurred.
2) RUN LED flicks and SD LED turns ON on the CC-Link Ver.2 board.
3) "-28158 (9202H) Driver WDT error" occurs when accessing CC-Link Ver.2
board from the application program in which the CC-Link Ver.2 utility and
MELSEC data link library function are used.
POINT
(1) When the multiple applications in which MELSEC data link library is used are
executed, driver WDT error is returned to all the programs. However, only the
CC-Link Ver.2 board in which the driver WDT error has occurred is recognized
as an error station on the network.
When using driver WDT function, set the monitoring timer considering the
margin of the personal computer load.
(2) For the troubleshooting, refer to section 16.4.2.