3.4.15 Operation Setting Area for Bus Off Error
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This area is used to set whether or not to reset the CAN chip (communication chip) of
the QJ71DN91 to resume the communication if a bus off error occurs.
(1) Operation Setting Area for Bus Off Error (address: 0632
Set whether or not to reset the QJ71DN91's CAN chip (communication chip) to
resume the communication if a bus off error occurs.
Setting "1" in this area enables communication resumption without resetting the
Configure this setting before starting I/O communication (before setting I/O
Communication Request (Y11) to on).
If "1" is set in this area after a bus off error occurs, the CAN chip is not reset.
0: Stop communication without resetting the CAN chip (default)
1: Resume communication by resetting the CAN chip
*: When any value other than 0 and 1 is set, the CAN chip is not reset.
Confirming a bus off error
A bus off error can be confirmed by a LED and relevant values in the buffer
The NS LED on the QJ71DN91 turns on red.
How many times the error occurred is stored in Bus Error Counter
After resetting the CAN chip
When the CAN chip is reset, the LED indication and buffer memory values
are changed as follows:
When the CAN chip is reset, the NS LED status on the QJ71DN91
changes as follows: turning on (red)
remaining on (green).
Values in Bus Error Counter (address: 01B2
) and Bus Off Counter (address: 01B3
) are not cleared even if the CAN chip is reset.
) and Bus Off Counter
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