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User manual SCAIME:
NU-Soft-eNod4F-E-0716_235704-C.doc
Boot-up
X
X
Heartbeat
X
X
X
X
X
X
5.5.1
NMT commands
Except during the initialization phase,
eNod4
is able to handle any NMT master’s requests for changing its c
urrent
state. All these network management messages are constituted the same way:
a two-byte data frame with a COB-ID
equal to zero:
The 2
nd
byte of the data field contains the node identifier of the device concerned by the request. Its value must be
between 0
H
and 7F
H
. The 0
H
value means that the NMT command concern all the nodes of the network.
The 1
st
byte codes the command sent to the node. There are five existing commands supported:
« Start node »
: 01
H
.
eNod4
is set into
operational
state
« Stop node »:
02
H
.
eNod4
is set into
stopped
state
« Reset node »
: 81
H
. Resets
eNod4
(with the same effects as a power-up), back into
initialization
state.
« Reset communication »
: 82
H
. Back into
initialization
state and communication parameters
reset.
« Enter pre-operational mode »
: 80
H
.
eNod4
is set into
pre-operational
state
5.5.2
Synchronization messages
SYNC messages are emitted on the bus by a producer node (generally the NMT master). This service is unconfirmed so
the consumer nodes do not have to respond to SYNC messages. A SYNC message does not carry any data (DLC = 0).
eNod4
is only seen as a SYNC messages consumer whose COB-ID is stored at index 1005
H
, sub-index 00
H
of the object
dictionary.
5.5.3
Emergency messages
eNod4
internal errors are reported via emergency frames. Two types of errors can trigger the transmission of an
emergency message:
▪
communication errors
▪
A/D converter input signal range exceeded
Every emergency frame is built as follows:
COB-ID
DLC
byte 0 byte 1
byte 2
byte 3 byte 4 byte 5 byte 6 byte 7
80
H
+ ID
eNod4
8
emergency code
error register
content
additional information
Emergency message is an unconfirmed service. A frame is emitted when a new error occurs and when it is
acknowledged. The table below describes the emergency standard codes supported by
e
Nod4-
T
and the translation of
the additional information bytes (in ASCII
):
Emergency codes (hex.)
Meaning
0
error acknowledged
3200
voltage error
8120
CAN bus communication error
8130
life guard error
Additional information’s (hex.)
4B4F
no error
474C
life time has elapsed or Heart Beat not received
COB-ID
DLC
byte 1
byte 2
0
2
NMT code
Node identifier
