
1.DeviceNet FUNCTIONS OPERATION B-63404EN/03
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Table 1.2.1 (b) (continued): Diagnostics information
(STATUS/COMMUNICATION STATUS)
Item Description
COMMUNICATION
STATUS:
CAN BUS STATUS1
#2 BO (0) : Bus OFF state
A communications error has
occurred, and the CAN chip
automatically turned offline. Probable
causes are an incorrect baud rate
setting or a hardware malfunction.
#3 A (1) : Network is active.
Data is being sent and received.
#4 TA (0) : Response error state
There is no response from the
communications destination within 25
to 50 msec. The communications
destination node may not exist on the
network.
#5 TO (0) : Time-out state
High priority data may be being
transferred excessively.
#6 RO (0) : Receive buffer overrun has occurred.
#7 ML (0) : Message lost has occurred.
CAN BUS STATUS2 (1byte Data)
#7 #6 #5 #4 #3 #2 #1 #0
COMMUNICATION
STATUS:
CAN BUS STATUS2
[SA] [05] [02] [01] [--] [--] [BP] [ER]
The meaning of ‘1’ of each bit is as follows.
(Values in parentheses () indicate values in the
normal communications status.)
#0 ER (0) : A CAN communications error has
occurred.
A probable cause is noise or a
hardware malfunction.
#1 BP (1) : Network power ON state
#2 --
#3 --
#4 01 : Baud rate is 125 kbps.
#5 02 : Baud rate is 250 kbps.
#6 05 : Baud rate is 500 kbps.
#7 SA (1) : The network scanner is active.