Bfm #26] From/To Watchdog; Bfm #27] Node Address; Bfm #29] Error Status; Bfm #30] Module Id Code - Mitsubishi Electric MELSEC-F FX3U-CAN User Manual

FX -CAN User's Manual
3U
6.9

[BFM #26] FROM/TO Watchdog

The FROM/TO Watchdog can be used when the Module is online to monitor if the PLC program accesses
data BFM #0 to BFM #19, BFM #100 to #399 or BFM #3000 to BFM #3539 cyclically.
After the first FROM/TO on the data BFM, the Watchdog will check if the next access to the data BFM takes
place before the time set in BFM #26 expires.
BFM #26 sets the Watchdog timer in 10 ms steps (default value K20 equals 200 ms).
Note
• If the watchdog expires, bit 7 in BFM #29 is set to ON, and the messages defined in the BFM #1900 to
#1927 "PLC RUN>STOP messages" area or an EMCY Object are transmitted on the network. If the
module is in a CANopen
object (Index H1029) in the object dictionary.
• If the watchdog function is not required, it can be deactivated by writing K0 to BFM #26.
• The FROM/TO watchdog can be restarted by writing the setting value to BFM #26 again, which will also
reset the error flag in BFM #29.
6.10

[BFM #27] Node Address

This BFM sets CANopen
Note
• The BFM setting needs to be stored by BFM #22 bit 0 and afterwards be restarted by BFM #25 bit 0 to
make the new setting effective.
• A setting out of the above range or a write access in Layer-2 function mode will generate a Failure
Message in BFM #29 bit 6.
6.11

[BFM #29] Error Status

For further information on error status, refer to the following section.
6.12

[BFM #30] Module ID Code

The identification code for FX
FX -CAN is K7170. By reading this identification code, the user may create built-in checking routines in the
3U
PLC program to check whether the physical position of the FX
matches the program.
116
®
Mode, the module will react according to the value set in the Error behavior
®
Node-ID. The setting value range is 1 to 127.
-CAN is available using a FROM instruction. The identification code for the
3U
→ For PLC RUN>STOP messages, refer to Section 9.6
→ For EMCY Object, refer to Subsection 5.6.13
→ For Error behaviour object, refer to Section 5.7
-CAN on the special function unit bus
3U
6 Allocation of Buffer Memories
6.9 [BFM #26] FROM/TO Watchdog
→ Refer to Section 14.2